bluuebunny/crossref_metadata_2025 huggingface dataset:
Numerical simulation of the multiple core localized low shear toroidal Alfvenic eigenmodes
Authors: Wang Wenjia , Zhou Deng , Hu Youjun , Ming Yue
Published: March 2018

In modern tokamak experiments, scenarios with weak central magnetic shear has been proposed. It is necessary to study the Alfvenic mode activities in such scenarios. Theoretical researches have predicted the multiplicity of core-localized toroidally induced Alfvenic eigenmodes for ε/s > 1, where ε is the inverse aspect ratio and s is magnetic shear. We numerically investigate the existence of multiplicity of core-localized TAEs and mode characteristics using NOVA code in the present work. We firstly verify the existence of the multiplicity for zero beta plasma and the even mode at the forbidden zone. For finite beta plasma, the mode parities become more distinguishable, and the frequencies of odd modes are close to the upper tip of the continuum, while the frequencies of even modes are close to the lower tip of the continuum. Their frequencies are well separated by the forbidden zone. With the increasing value of ε/s, more modes with multiple radial nodes will appear, which is in agreement with theoretical prediction. The discrepancy between theoretical prediction and our numerical simulation is also discussed in the main text.
Improvement of electronic and thermoelectric properties of the metallic LaS by sodium substitution: From first-principles calculations
Authors: Si Mohammed D. E. , Seddik T. , Batouche M. , Merabiha O. , Zanoun A.
Published: March 2018

In this manuscript, the structural, electronic, and thermoelectric properties of Na doped binary LaS have been studied by means of the full-potential augmented plane wave plus local orbital's method. The Wu-Cohen generalized gradient and the Tran-Blaha modified Becke-Johnson (TB-mBJ) approximations have been employed to describe the exchange-correlation potential. Examining the composition effect on the electronic properties, we point out that LaS compound and Na0.25La0.75S alloy have a metallic behavior. On the other hand, both Na0.5La0.5S and Na0.75La0.25S alloys show a semiconductor behavior with direct bandgap equal to 1.26 and 2.8 eV, using the TB-mBJ approximation, respectively. Moreover, the thermoelectric properties of LaS are enhanced, especially for 50% and 75% of Na concentration. Consequently, the estimated ZT value of about 0.75 at room temperature proves that Na doped metal LaS makes it a promising candidate for thermoelectric applications.
Increasing the magnetic-field capability of the magneto-inertial fusion electrical discharge system using an inductively coupled coil
Authors: Barnak D. H. , Davies J. R. , Fiksel G. , Chang P.-Y. , Zabir E. , Betti R.
Published: March 2018

Magnetized high energy density physics (HEDP) is a very active and relatively unexplored field that has applications in inertial confinement fusion, astrophysical plasma science, and basic plasma physics. A self-contained device, the Magneto-Inertial Fusion Electrical Discharge System, MIFEDS [G. Fiksel et al., Rev. Sci. Instrum. 86, 016105 (2015)], was developed at the Laboratory for Laser Energetics to conduct magnetized HEDP experiments on both the OMEGA [T. R. Boehly et al., Opt. Commun. 133, 495–506 (1997)] and OMEGA EP [J. H. Kelly et al., J. Phys. IV France 133, 75 (2006) and L. J. Waxer et al., Opt. Photonics News 16, 30 (2005)] laser systems. Extremely high magnetic fields are a necessity for magnetized HEDP, and the need for stronger magnetic fields continues to drive the redevelopment of the MIFEDS device. It is proposed in this paper that a magnetic coil that is inductively coupled rather than directly connecting to the MIFEDS device can increase the overall strength of the magnetic field for HEDP experiments by increasing the efficiency of energy transfer while decreasing the effective magnetized volume. A brief explanation of the energy delivery of the MIFEDS device illustrates the benefit of inductive coupling and is compared to that of direct connection for varying coil size and geometry. A prototype was then constructed to demonstrate a 7-fold increase in energy delivery using inductive coupling.
Thermophysical and radiation properties of high-temperature C4F8-CO2 mixtures to replace SF6 in high-voltage circuit breakers
Authors: Zhong Linlin , Cressault Yann , Teulet Philippe
Published: March 2018

C4F8-CO2 mixtures are one of the potential substitutes to SF6 in high-voltage circuit breakers. However, the arc quenching ability of C4F8-CO2 mixtures is still unknown. In order to provide the necessary basic data for the further investigation of arc quenching performance, the compositions, thermodynamic properties, transport coefficients, and net emission coefficients (NEC) of various C4F8-CO2 mixtures are calculated at temperatures of 300–30 000 K in this work. The thermodynamic properties are presented as the product of mass density and specific heat, i.e., ρCp. The transport coefficients include electrical conductivity, viscosity, and thermal conductivity. The atomic and molecular radiation are both taken into account in the calculation of NEC. The comparison of the properties between SF6 and C4F8-CO2 mixtures is also discussed to find their differences. The results of compositions show that C4F8-CO2 mixtures have a distinctive advantage over other alternative gases e.g., CF3I and C3F8, because the dissociative product (i.e., C4F6) of C4F8 at low temperatures has a very high dielectric strength. This is good for an arc quenching medium to endure the arc recovery phase. Compared with SF6, C4F8-CO2 mixtures present lower ρCp at temperatures below 2800 K and larger thermal conductivity above 2800 K. Based on the position of peaks in thermal conductivity, we predict that the cooling of C4F8-CO2 arc will be slowed down at higher temperatures than that of SF6 arc. It is also found that the mixing of CO2 shows slight effects on the electrical conductivity and NEC of C4F8-CO2 mixtures.
Application of Legendre spectral-collocation method to delay differential and stochastic delay differential equation
Authors: Khan Sami Ullah , Ali Ishtiaq
Published: March 2018

Explicit solutions to delay differential equation (DDE) and stochastic delay differential equation (SDDE) can rarely be obtained, therefore numerical methods are adopted to solve these DDE and SDDE. While on the other hand due to unstable nature of both DDE and SDDE numerical solutions are also not straight forward and required more attention. In this study, we derive an efficient numerical scheme for DDE and SDDE based on Legendre spectral-collocation method, which proved to be numerical methods that can significantly speed up the computation. The method transforms the given differential equation into a matrix equation by means of Legendre collocation points which correspond to a system of algebraic equations with unknown Legendre coefficients. The efficiency of the proposed method is confirmed by some numerical examples. We found that our numerical technique has a very good agreement with other methods with less computational effort.
Stabilized antiferroelectricity in xBiScO3-(1-x)NaNbO3 lead-free ceramics with established double hysteresis loops
Authors: Gao Lisheng , Guo Hanzheng , Zhang Shujun , Randall Clive A.
Published: March 2018

We previously reported various solid solution systems that demonstrated the stabilized antiferroelectric (P) phases in NaNbO3 through lowering the tolerance factor. However, all those reported modifications were achieved by adding A2+B4+O3 type solid solutions. A lead-free antiferroelectric (AFE) solid solution xBiScO3-(1-x)NaNbO3 was rationalized by adopting the tolerance factor design rule. Specifically, adding BiScO3 was found to effectively stabilize the AFE phase without changing the crystal symmetry of NaNbO3. Microstructure and electron zone axis diffraction patterns from transmission electron microscopy revealed the stabilized AFE (P) phase in this solid solution. Besides, the electric-field-induced polarization with a double-hysteresis loop was observed. The present results pointed out that the strategy could also be applied while adding A3+B3+O3 type solid solutions. In addition, it expanded the compositional design that can be applied to antiferroelectric materials.
Quasi continuous wave laser sintering of Si-Ge nanoparticles for thermoelectrics
Authors: Xie Kai , Mork Kelsey , Held Jacob T. , Mkhoyan K. Andre , Kortshagen Uwe , Gupta Mool C.
Published: March 2018

Silicon-germanium is an important thermoelectric material for high temperature applications. In this study, thin films composed of SiGe nanoparticles were synthesized in a plasma reactor and sintered by a millisecond pulse width, quasi continuous wave, near infrared laser of wavelength 1070 nm. We demonstrate that laser sintered SiGe thin films have high electrical and low thermal conductivity, dependent on the surface morphology and dopant concentration. Substrate wetting of laser heating induced molten SiGe was found to play an important role in the final surface morphology of the films. Interconnected percolation structures, formed when proper substrate wetting occurs, were found to be more conductive than the balling structure that formed with insufficient wetting. Laser power was adjusted to maximize dopant reactivation while still minimizing dopant evaporation. After optimizing laser sintering process parameters, the best electrical conductivity, thermal conductivity, and Seebeck coefficient were found to be 70.42 S/cm, 0.84 W/m K, and 133.7 μV/K, respectively. We demonstrate that laser sintered SiGe thin films have low thermal conductivity while maintaining good electrical conductivity for high temperature thermoelectric applications.
Urea controlled hydrothermal synthesis of ammonium aluminum carbonate hydroxide rods
Authors: Wang Fang , Zhu Jianfeng , Liu Hui
Published: March 2018

In this study, ammonium aluminum carbonate hydroxide (AACH) rods were controllably prepared using the hydrothermal method by manipulating the amount of urea in the reaction system. The experimental results showed that AACH in rod shape was able to be gradually transformed from γ-AlOOH in cluster shape during the molar ratios of urea to Al in the reactants were ranged from 8 to 10, and the yield of AACH has increased accordingly. When the molar ratio of urea to Al reaches 11, pure AACH rods with a diameter of 500 nm and a length of 10 μm approximately was able to be produced. Due to the slow decomposition of urea during the hydrothermal reaction, the nucleation and growth of AACH crystal proceed step by step. Therefore, the crystal can fully grow on each crystal plane and eventually produce a highly crystalline rod-shaped product. The role of urea in controlling the morphology and yield of AACH was also discussed in this paper systematically.
Achieving highly efficient and broad-angle polarization beam filtering using epsilon-near-zero metamaterials mimicked by metal-dielectric multilayers
Authors: Wu Feng
Published: March 2018

We report a highly efficient and broad-angle polarization beam filter at visible wavelengths using an anisotropic epsilon-near-zero metamaterial mimicked by a multilayer composed of alternative subwavelength magnesium fluoride and silver layers. The underlying physics can be explained by the dramatic difference between two orthogonal polarizations' iso-frequency curves of anisotropic epsilon-near-zero metamaterials. Transmittance for two orthogonal polarization waves and the polarization extinction ratio are calculated via the transfer matrix method to assess the comprehensive performance of the proposed polarization beam filter. From the simulation results, the proposed polarization beam filter is highly efficient (the polarization extinction ratio is far larger than two orders of magnitude) and has a broad operating angle range (ranging from 30° to 75°). Finally, we show that the proper tailoring of the periodic number enables us to obtain high comprehensive performance of the proposed polarization beam filter.
Role of plasma-induced defects in the generation of 1/f noise in graphene
Authors: Cultrera Alessandro , Callegaro Luca , Marzano Martina , Ortolano Massimo , Amato Giampiero
Published: March 2018

It has already been reported that 1/f noise in graphene can be dominated by fluctuations of charge carrier mobility. We show here that the increasing damage induced by oxygen plasma on graphene samples result in two trends: at low doses, the magnitude of the 1/f noise increases with the dose; and at high doses, it decreases with the dose. This behaviour is interpreted in the framework of 1/f noise generated by carrier mobility fluctuations where the concentration of mobility fluctuation centers and the mean free path of the carriers are competing factors.
Real-time synchronous measurement of curing characteristics and polymerization stress in bone cements with a cantilever-beam based instrument
Authors: Palagummi Sri Vikram , Landis Forrest A. , Chiang Martin Y. M.
Published: March 2018

An instrumentation capable of simultaneously determining degree of conversion (DC), polymerization stress (PS), and polymerization exotherm (PE) in real time was introduced to self-curing bone cements. This comprises the combination of an in situ high-speed near-infrared spectrometer, a cantilever-beam instrument with compliance-variable feature, and a microprobe thermocouple. Two polymethylmethacrylate-based commercial bone cements, containing essentially the same raw materials but differ in their viscosity for orthopedic applications, were used to demonstrate the applicability of the instrumentation. The results show that for both the cements studied the final DC was marginally different, the final PS was different at the low compliance, the peak of the PE was similar, and their polymerization rates were significantly different. Systematic variation of instrumental compliance for testing reveals differences in the characteristics of PS profiles of both the cements. This emphasizes the importance of instrumental compliance in obtaining an accurate understanding of PS evaluation. Finally, the key advantage for the simultaneous measurements is that these polymerization properties can be correlated directly, thus providing higher measurement confidence and enables a more in-depth understanding of the network formation process.
Toward engineering
E. coli
with an autoregulatory system for lignin valorization
Authors: Wu Weihua , Liu Fang , Singh Seema
Published: March 2018

Significance

Lignin valorization is critical for economic viability of future biorefineries but is hindered due to the challenges of engineered bio-chassis such as the slow kinetics of substrate uptake, aromatics toxicity, and cost. Here, an autoregulatory system involving a vanillin autoinducible promoter is demonstrated with an aromatics transporter in
Escherichia coli
that is induced by lignin-derived aromatics and simultaneously converted to value-added platform chemical with diverse applications. In addition to alleviating toxicity, the engineered
E. coli
strain eliminates the need for an external inducer such as isopropyl β-
d
-1-thiogalactopyranoside during fermentation, thereby significantly reducing the process cost. This study demonstrates an autoregulatory system for aromatics bioconversion and serves as a platform for future strain development for lignin valorization.
The effect of explanatory captions on the reception of foreign audiovisual products
Authors: Zheng Binghan , Xie Mingqing
Published: March 2018

The present research triangulates questionnaire, retrospective interview and eyetracking data, aiming to investigate how Explanatory Captions (ECs) are received by different viewers with varied educational backgrounds, and whether or not the presence of ECs improves their understanding of the AV content. The results show that the provision of ECs, for a subtitled video in a foreign language, greatly increased positive cognitive effects on the viewers. Viewers tend to reduce time spent on viewing images, but invest additional processing effort on the ECs, although their allocation of processing effort on subtitles experienced little change. Furthermore, the eyetracking data suggest that most participants adopted a fixed reading pattern on subtitles and ECs when they appeared simultaneously, which could balance some of the negative impact of ECs on their viewing experience. The findings gained through this experimental research will provide some guidance and suggestions for subtitlers when preparing subtitles and ECs.
Release behavior of allyl sulfide from cyclodextrin inclusion complex of allyl sulfide under different storage conditions
Authors: Nguyen Thi Van Anh , Yoshii Hidefumi
Published: March 2018

The stability of allyl sulfide, an organosulfur compound present in garlic oil, in its α-, β-, and γ-cyclodextrin inclusion complexes was investigated under various storage conditions. The complexes of cyclodextrins and allyl sulfide were prepared by spray drying. The storage temperature, relative humidity, and initial moisture content of the inclusion complex had different effects on the release rate of allyl sulfide. Allyl sulfide in α-cyclodextrin complexes had a lower release rate than in β- and γ-cyclodextrin complexes at 100 °C and at 50 °C under 6, 40, 54, and 73% relative humidity. The initial moisture content affected only the release rate of allyl sulfide from α-cyclodextrin complexes. The release behavior of allyl sulfide can be correlated with the first-order release rate equation with a normal Gaussian distribution of free energy of activation of release rate constant. The results indicated α-cyclodextrin is a suitable material for controlled release of allyl sulfide.
Growth of Mycobacterium tuberculosis in vivo segregates with host macrophage metabolism and ontogeny
Authors: Huang Lu , Nazarova Evgeniya V. , Tan Shumin , Liu Yancheng , Russell David G.
Published: March 2018

To understand how infection by Mycobacterium tuberculosis (Mtb) is modulated by host cell phenotype, we characterized those host phagocytes that controlled or supported bacterial growth during early infection, focusing on the ontologically distinct alveolar macrophage (AM) and interstitial macrophage (IM) lineages. Using fluorescent Mtb reporter strains, we found that bacilli in AM exhibited lower stress and higher bacterial replication than those in IM. Interestingly, depletion of AM reduced bacterial burden, whereas depletion of IM increased bacterial burden. Transcriptomic analysis revealed that IMs were glycolytically active, whereas AMs were committed to fatty acid oxidation. Intoxication of infected mice with the glycolytic inhibitor, 2-deoxyglucose, decreased the number of IMs yet increased the bacterial burden in the lung. Furthermore, in in vitro macrophage infections, 2-deoxyglucose treatment increased bacterial growth, whereas the fatty acid oxidation inhibitor etomoxir constrained bacterial growth. We hypothesize that different macrophage lineages respond divergently to Mtb infection, with IMs exhibiting nutritional restriction and controlling bacterial growth and AMs representing a more nutritionally permissive environment.
Predicting sustainable shark harvests when stock assessments are lacking
Authors: Bradshaw Corey J A , Prowse Thomas A A , Drew Michael , Gillanders Bronwyn M , Donnellan Steven C , Huveneers Charlie
Published: March 2018

Effective fisheries management generally requires reliable data describing the target species’ life-history characteristics, the size of its harvested populations, and overall catch estimates, to set sustainable quotas and management regulations. However, stock assessments are often not available for long-lived marine species such as sharks, making predictions of the long-term population impacts of variable catch rates difficult. Fortunately, stage- or age-structured population models can assist if sufficient information exists to estimate survival and fertility rates. Using data collected from the bronze whaler (Carcharhinus brachyurus) fishery in South Australia as a case study, we estimated survival probabilities from life tables of harvested individuals, as well as calculated natural mortalities based on allometric predictions. Fertility data (litter size, proportion mature) from previous studies allowed us to build a fertility vector. Deterministic matrices built using estimates of life-table data or natural mortality (i.e. harvested-augmented and natural mortality) produced instantaneous rates of change of 0.006 and 0.025, respectively. Assuming an incrementing total catch at multiples of current rates, stochastic simulations suggest the relative rate of population decline starts to become precipitous around 25% beyond current harvest rates. This is supported by a sharp increase in weighted mean age of the population around 25% increase on current catches. If the catch is assumed to be proportional (i.e. a constant proportion of the previous year’s population size), the relative r declines approximately linearly with incrementing harvest beyond the current rate. A global sensitivity analysis based on a Latin-hypercube sampling design of seven parameters revealed that variation in the survival estimates derived from the life tables was by far the dominant (boosted-regression tree relative influence score = 91.14%) determinant of model performance (measured as variation in the long-term average rate of population change r). While current harvest rates therefore appear to be sustainable, we recommend that fisheries-management authorities attempt to sample a broader size range of individuals (especially older animals) and pursue stock assessments. Our models provide a framework for assessing the relative susceptibility of long-lived fishes to harvest pressure when detailed stock data are missing.
Giant galaxy growing from recycled gas: ALMA maps the circumgalactic molecular medium of the Spiderweb in [C i]
Authors: Emonts B H C , Lehnert M D , Dannerbauer H , De Breuck C , Villar-Martín M , Miley G K , Allison J R , Gullberg B , Hatch N A , Guillard P , Mao M Y , Norris R P
Published: March 2018

The circumgalactic medium (CGM) of the massive Spiderweb Galaxy, a conglomerate of merging proto-cluster galaxies at z = 2.2, forms an enriched interface where feedback and recycling act on accreted gas. This is shown by observations of [C i], CO(1-0), and CO(4-3) performed with the Atacama Large Millimeter Array and Australia Telescope Compact Array. [C i] and CO(4-3) are detected across ∼50 kpc, following the distribution of previously detected low-surface-brightness CO(1-0) across the CGM. This confirms our previous results on the presence of a cold molecular halo. The central radio galaxy MRC 1138-262 shows a very high global $L^{\prime}_{\rm CO(4-3)}$/$L^{\prime}_{\rm CO(1-0)}$ ∼ 1, suggesting that mechanisms other than FUV-heating by star formation prevail at the heart of the Spiderweb Galaxy. Contrary, the CGM has $L^{\prime}_{\rm CO(4-3)}$/$L^{\prime}_{\rm CO(1-0)}$ and $L^{\prime}_{\rm [C\,I]}$/$L^{\prime}_{\rm CO(1-0)}$ similar to the ISM of five galaxies in the wider proto-cluster, and its carbon abundance, $X_{\rm [C\,I]}$/$X_{\rm H_2}$, resembles that of the Milky Way and star-forming galaxies. The molecular CGM is thus metal-rich and not diffuse, confirming a link between the cold gas and in situ star formation. Thus, the Spiderweb Galaxy grows not directly through accretion of gas from the cosmic web, but from recycled gas in the CGM.
Increased Body Mass Index Associated With Reduced Risk of Delayed Cerebral Ischemia and Subsequent Infarction After Aneurysmal Subarachnoid Hemorrhage
Authors: Rinaldo Lorenzo , Rabinstein Alejandro A , Lanzino Giuseppe
Published: March 2018

BACKGROUND

Increased body mass index (BMI) may be protective against cerebral ischemia in certain clinical contexts.

OBJECTIVE

To investigate whether increased BMI was associated with delayed cerebral ischemia (DCI) and subsequent infarction after aneurysmal subarachnoid hemorrhage (aSAH).

METHODS

We retrospectively reviewed the clinical course of patients presenting to our institution for management of aSAH. Patient were segregated according to BMI< or ≥29.4, a value determined by Classification and Regression Tree analysis. Predictors of DCI and delayed infarction were identified using stepwise multivariate logistic regression analysis.

RESULTS

There were 161 patients included for analysis. Average BMI within our patient cohort was 28.9, with 67 patients presenting with a BMI of ≥29.4 on admission. DCI occurred in 50 patients (31.1%) and was complicated by delayed infarction in 15 patients (9.3%). On stepwise multivariate analysis, BMI ≥ 29.4 was independently associated with reduced likelihood of DCI (odds ratio [OR] 0.42, 95% confidence interval [CI] 0.18-0.92) and delayed infarction (OR 0.13, 95% CI 0.02-0.61; P = .008). Increasing maximum flow velocity on transcranial Doppler ultrasound was independently associated with increased odds of both DCI (Unit OR 1.19, 95% CI 1.09-1.30; P < .001) and delayed infarction (Unit OR 1.31, 95% CI 1.13-1.56; P < .001), while intracerebral hemorrhage was independently associated with increased odds of delayed infarction (OR 6.99, 95% CI 1.82-30.25; P = .005).

CONCLUSION

We report an association between elevated BMI and reduced incidence of DCI and delayed infarction, suggesting a protective effect of increasing BMI on the risk of ischemic complications after aSAH.
Taxonomically Different Co-Microsymbionts of a Relict Legume, Oxytropis popoviana, Have Complementary Sets of Symbiotic Genes and Together Increase the Efficiency of Plant Nodulation
Authors: Safronova Vera I. , Belimov Andrey A. , Sazanova Anna L. , Chirak Elizaveta R. , Verkhozina Alla V. , Kuznetsova Irina G. , Andronov Evgeny E. , Puhalsky Jan V. , Tikhonovich Igor A.
Published: March 2018

Ten rhizobial strains were isolated from root nodules of a relict legume Oxytropis popoviana Peschkova. For identification of the isolates, sequencing of rrs, the internal transcribed spacer region, and housekeeping genes recA, glnII, and rpoB was used. Nine fast-growing isolates were Mesorhizobium-related; eight strains were identified as M. japonicum and one isolate belonged to M. kowhaii. The only slow-growing isolate was identified as a Bradyrhizobium sp. Two strains, M. japonicum Opo-242 and Bradyrhizobium sp. strain Opo-243, were isolated from the same nodule. Symbiotic genes of these isolates were searched throughout the whole-genome sequences. The common nodABC genes and other symbiotic genes required for plant nodulation and nitrogen fixation were present in the isolate Opo-242. Strain Opo-243 did not contain the principal nod, nif, and fix genes; however, five genes (nodP, nodQ, nifL, nolK, and noeL) affecting the specificity of plant-rhizobia interactions but absent in isolate Opo-242 were detected. Strain Opo-243 could not induce nodules but significantly accelerated the root nodule formation after coinoculation with isolate Opo-242. Thus, we demonstrated that taxonomically different strains of the archaic symbiotic system can be co-microsymbionts infecting the same nodule and promoting the nodulation process due to complementary sets of symbiotic genes.
Pharmacokinetic Properties of a Sufentanil Sublingual Tablet Intended to Treat Acute Pain
Authors: Fisher Dennis M. , Chang Peter , Wada D. Russell , Dahan Albert , Palmer Pamela P.
Published: March 2018

Background

Desirable product attributes for treatment of moderate-to-severe acute pain in many medically supervised settings are rapid onset and a route of administration not requiring intravenous access. The pharmacokinetic characteristics of sublingually administered tablets containing 15 or 30 µg of sufentanil are described.

Methods

Blood was sampled from healthy subjects (four studies, 122 subjects) and patients (seven studies, 944 patients). Studies in healthy subjects determined bioavailability, effect of inhibition of cytochrome P450 3A4, and the plasma concentration profile with single and hourly sublingual doses. Studies in patients evaluated effects of weight, age, sex, and organ impairment on apparent clearance. Noncompartmental and mixed-effect population methods were used.

Results

Bioavailability of a single sublingual tablet was 52%, decreasing to 35% with repeat dosing. Ketoconazole (CYP3A4 inhibitor) increased maximum plasma concentration 19% and increased the area under the curve 77%. After a single 30-µg dose, plasma concentrations reached the published sufentanil analgesic threshold (24 pg/ml) within 30 min, peaked at 1 h, and then decreased below therapeutic concentrations by ~3 h. With hourly administration, plasma concentrations plateaued by the fifth dose. Time for concentrations to decrease 50% from maximal values was similar after 1 dose (2.5 ± 0.85 h) and 12 doses (2.5 ± 0.72 h). Clearance increased with weight, decreased with age, and was not affected by renal or hepatic impairment.

Conclusions

The time course of a single 30-µg dose was consistent with onset of analgesia and redosing frequency observed in clinical trials. Sublingual sufentanil tablets provide the opportunity to noninvasively and rapidly treat moderate-to-severe pain in a monitored setting.
Comparison of Transcutaneous and Serum Bilirubin Measurements in Neonates 30 to 34 JOURNAL/ancr/04.03/00149525-201804000-00012/12FSM1/v/2023-07-21T043933Z/r/image-gif Weeks' Gestation Before, During, and After Phototherapy
Authors: Jnah Amy , Newberry Desi M. , Eisenbeisz Elaine
Published: March 2018

Background:

The use of noninvasive, transcutaneous bilirubin monitoring (TcB) as a jaundice screen in full-term infants is well established; however, there is a paucity of research evaluating the use of TcB in premature infants.

Purpose:

To compare agreement and consistency of transcutaneous and serum bilirubin measurements in a multiracial premature infant population ranging from 30 to 34

JOURNAL/ancr/04.03/00149525-201804000-00012/12FSM1/v/2023-07-21T043933Z/r/image-gif

weeks' gestation before, during, and after phototherapy.

Methods:

Forty-five neonates, 30 to 34

JOURNAL/ancr/04.03/00149525-201804000-00012/12FSM1/v/2023-07-21T043933Z/r/image-gif

weeks' gestation, were enrolled in this prospective, correlational study over a 12-month period. One set of paired transcutaneous and serum bilirubin measurements, per neonate, was obtained before phototherapy, during therapy, and after phototherapy. Exclusion criteria included neonates with positive direct coombs test or evidence of hemolytic disease, major congenital anomalies, hydrops fetalis, and those not expected to survive.

Results:

There was a strong, positive correlation between TcB and total serum monitoring (TSB) measurements obtained pretherapy (r = 0.797, P < .001). A moderate correlation was noted between TcB and TSB measurements obtained during therapy (r = 0.588, P < .001). A strong correlation was noted between TcB and TSB measurements obtained posttherapy (r = 0.869, P < .001). There were no significant differences between paired samples across time (F = 0.891, P = .41, partial η2 = 0.01). The TSB measurements were consistently lower than TcB pretherapy, during, and posttherapy.

Implications for Practice:

The TcB measurements provide a reliable estimation, generally within 2 to 3 mg/dL of TSB levels, in premature infants 30 to 34

JOURNAL/ancr/04.03/00149525-201804000-00012/12FSM1/v/2023-07-21T043933Z/r/image-gif

weeks' gestation.

Implications for Research:

Investigation of consumption of time and nursing personnel required to perform TcB testing, compared with TSB testing, is indicated. Cost analyses comparing TcB-driven screening protocols and interval TSB measurements, among premature infants, are indicated. As newer generations of TcB devices are approved for use, additional studies using mixed-race populations of premature infants will be necessary to continue to evaluate the reliability and validity of this screening tool within the everyday neonatal intensive care unit.
Ultrasound-Guided Laryngeal Air Column Width Difference as a New Predictor for Postextubation Stridor in Children
Authors: El Amrousy Doaa , Elkashlan Mohamed , Elshmaa Nagat , Ragab Ahmed
Published: March 2018

Objectives:

To assess the efficacy of ultrasound-guided laryngeal air column width difference in predicting postextubation stridor in children.

Design:

Prospective observational study.

Setting:

Single, tertiary care pediatric hospital.

Patients:

This study was carried out at PICU and surgical ICU, Tanta University Hospital on 400 ventilated children between January 2015 and May 2017. Patients who received mechanical ventilation and met criteria for a weaning trial were included.

Intervention:

Laryngeal ultrasound and cuff leak test.

Measurements and Main Results:

Ultrasound-guided laryngeal air column width and cuff leak test were measured before extubation. Laryngeal air column width is the width of air between the vocal cords seen by laryngeal ultrasonography. Laryngeal air column width difference is the width difference of air column passed through vocal cords with the balloon cuff inflated and deflated. Three-hundred fifty six patients (89%) had no postextubation stridor, whereas 44 patients (11%) developed postextubation stridor. Postextubation stridor was associated with younger age, less weight, female gender, prolonged duration of intubation, and ICU stay (p < 0.05). Both laryngeal air column width difference and cuff leak test showed significant decrease (p < 0.05) in patients with postextubation stridor in comparison with no postextubation stridor patients. Receiver operating characteristics curve analysis showed that laryngeal air column width difference at cutoff point of less than 0.8 mm gave a sensitivity of 93%, specificity of 86%, and accuracy of 91%, whereas cuff leak test at less than 11% yielded a sensitivity of (61%), specificity of (53%), and accuracy of (59%) for predicting postextubation stridor.

Conclusions:

Laryngeal air column width difference measurement may serve as a simple reliable noninvasive method for predicting postextubation stridor in children.
Noninvasive Ventilation in Patients With Do-Not-Intubate and Comfort-Measures-Only Orders: A Systematic Review and Meta-Analysis*
Authors: Wilson Michael E. , Majzoub Abdul M. , Dobler Claudia C. , Curtis J. Randall , Nayfeh Tarek , Thorsteinsdottir Bjorg , Barwise Amelia K. , Tilburt Jon C. , Gajic Ognjen , Montori Victor M. , Murad M. Hassan
Published: March 2018

Objectives:

To assess the effectiveness of noninvasive ventilation in patients with acute respiratory failure and do-not-intubate or comfort-measures-only orders.

Data Sources:

MEDLINE, EMBASE, CINAHL, Scopus, and Web of Science from inception to January 1, 2017.

Study Selection:

Studies of all design types that enrolled patients in the ICU or hospital ward who received noninvasive ventilation and had preset do-not-intubate or comfort-measures-only orders.

Data Extraction:

Data abstraction followed Meta-analysis of Observational Studies in Epidemiology guidelines. Data quality was assessed using a modified Newcastle-Ottawa Scale.

Data Synthesis:

Twenty-seven studies evaluating 2,020 patients with do-not-intubate orders and three studies evaluating 200 patients with comfort-measures-only orders were included. In patients with do-not-intubate orders, the pooled survival was 56% (95% CI, 49–64%) at hospital discharge and 32% (95% CI, 21–45%) at 1 year. Hospital survival was 68% for chronic obstructive pulmonary disease, 68% for pulmonary edema, 41% for pneumonia, and 37% for patients with malignancy. Survival was comparable for patients treated in a hospital ward versus an ICU. Quality of life of survivors was not reduced compared with baseline, although few studies evaluated this. No studies evaluated quality of dying in nonsurvivors. In patients with comfort-measures-only orders, a single study showed that noninvasive ventilation was associated with mild reductions in dyspnea and opioid requirements.

Conclusions:

A large proportion of patients with do-not-intubate orders who received noninvasive ventilation survived to hospital discharge and at 1 year, with limited data showing no decrease in quality of life in survivors. Provision of noninvasive ventilation in a well-equipped hospital ward may be a viable alternative to the ICU for selected patients. Crucial questions regarding quality of life in survivors, quality of death in nonsurvivors, and the impact of noninvasive ventilation in patients with comfort-measures-only orders remain largely unanswered.
Short-Latency Positive Peak Following N20 Somatosensory Evoked Potential Is Superior to N20 in Predicting Neurologic Outcome After Out-of-Hospital Cardiac Arrest
Authors: Kim Sung Wook , Oh Joo Suk , Park Jungtaek , Jeong Hyun Ho , Kim Ji Hoon , Wee Jung Hee , Oh Sang Hoon , Choi Seung Pill , Park Kyu Nam
Published: March 2018

Objectives:

The absence of N20 somatosensory evoked potential after cardiac arrest is related to poor outcome. However, discrimination between the low-amplitude and the absence of N20 is challenging. P25 and P30 are short-latency positive peaks with latencies between 25 and 30 ms following N20 (P25/30). P25/30 is evident even with an ambiguous N20 in patients with good outcome. Therefore, we evaluated the predictive value of P25/30 after cardiac arrest.

Design:

A retrospective observational study.

Setting:

University-affiliated hospital.

Subjects:

Comatose survivors after out-of-hospital cardiac arrest treated by hypothermic targeted temperature management.

Intervention:

None.

Measurements and Main Results:

The specificity and the positive predictive value of P25/30 and N20 in predicting poor outcome were the same, showing a rate of 100%. The sensitivity of P25/30 in predicting poor outcome (90.12% [95% CI, 81.5–95.6%]) was higher than that of N20 (70.37% [95% CI, 59.2–80%]). Also, the negative predictive value of P25/30 in predicting poor outcome (81.4% [95% CI, 69.4–89.4%]) was higher than that of N20 (59.3% [95% CI, 51–67.1%]). The P25/30-based adjusted model showed a larger area under the curve (0.98 [95% CI, 0.95–1]) compared with the N20-based adjusted model (0.95 [95% CI, 0.91–0.98]) (p = 0.02).

Conclusions:

The absence of P25/30 is related to poor outcome with a higher sensitivity, negative predictive value than the absence of N20.
When a Child Unexpectedly Draws a Violent Scene
Authors: Barnes Andy , Ziegler Richard , McConnico Neena , Stein Martin T.
Published: March 2018

CASE: Carter is a 12-year-old boy who has been seeing a developmental-behavioral pediatrician since the age of 7 years for problems with behavioral regulation. Around that time, he began to receive special education services after an educational assessment of autism. He has average intellectual abilities, with below-average semantic-pragmatic speech (e.g., conversations are one-sided). His medical diagnoses included attention-deficit hyperactivity disorder (ADHD), combined presentation, and generalized anxiety disorder. He has never met the DSM criteria for autistic spectrum disorder (ASD) because although he has atypical sensory behaviors (e.g., preoccupied with sniffing objects), he has otherwise lacked restricted, repetitive behaviors. Other medical problems include obesity.

His functional impairments associated with impulsivity, inattention, and anxiety improved with combined pharmacotherapy (a long-acting stimulant and a selective serotonin reuptake inhibitor [SSRI], on which he remains) and cognitive-behavioral therapy (CBT). After starting sixth grade, his Individualized Educational Plan (IEP) was modified to address his social impairments, with a self-contained classroom without windows. Soon thereafter, he began to talk about “hating myself” and developed mild-to-moderate depression, which improved after several weeks of a higher dose of SSRI and more frequent visits with his therapist.

Several weeks after starting seventh grade, the teacher sent an email to Carter's parents, which they forwarded to his developmental-behavioral pediatrician: “Carter drew a picture of himself shooting and stabbing a student he was mad at today (Fig. 1). He was very upset when I told him I was going to tell you. We haven't processed it through yet but I think a conversation at home about appropriate drawings and using other ways to calm down would help this not happen again.”
Does Nonmetropolitan Residence Impact Timely Chlamydia Treatment in Massachusetts?
Authors: Yoon Jungwon , Elder Heather R. , Hawrusik Rebecca , Klevens R. Monina , Roosevelt Kathleen A. , Hsu Katherine K.
Published: March 2018

A mean of 4.5 days until treatment was documented in a subset of reported laboratory-confirmed Massachusetts chlamydia cases selected for active case report form completion. Treatment delay was associated with longer test result turnaround time, and absence of symptoms or contact to sexually transmitted disease. Nonmetropolitan versus metropolitan residence did not appear to impact treatment time.
The conserved phosphatase GSP-2/PP1 promotes germline immortality via small RNA-mediated genome silencing during meiosis
Authors: Billmyre Katherine Kretovich , Doebley Anna-lisa , Heestand Bree , Belicard Tony , Sato-Carlton Aya , Flibotte Stephane , Simon Matt , Gnazzo Megan , Skop Ahna , Moerman Donald , Carlton Peter Mark , Sarkies Peter , Ahmed Shawn
Published: March 2018

Genomic silencing can promote germ cell immortality, or transgenerational maintenance of the germ line, via mechanisms that may occur during mitosis or meiosis. Here we report that thegsp-2PP1/Glc7 phosphatase promotes germ cell immortality. We identified a separation-of-function allele ofC. elegansGSP-2 that caused a meiosis-specific chromosome segregation defect and defects in transgenerational small RNA-induced genome silencing. GSP-2 is recruited to meiotic chromosomes by LAB-1, which also promoted germ cell immortality. Sterilegsp-2andlab-1mutant adults displayed germline degeneration, univalents and histone phosphorylation defects in oocytes, similar to small RNA genome silencing mutants. Epistasis and RNA analysis suggested that GSP-2 functions downstream of small RNAs. We conclude that a meiosis-specific function of GSP-2/LAB-1 ties small RNA-mediated silencing of the epigenome to germ cell immortality. Given that hemizygous genetic elements can drive transgenerational epigenomic silencing, and given that LAB-1 promotes pairing of homologous chromosomes and localizes to the interface between homologous chromosomes during pachytene, we suggest that discontinuities at this interface could promote nuclear silencing in a manner that depends on GSP-2.

Author Summary

The germ line of an organism is considered immortal in its capacity to give rise to an unlimited number of future generations. To protect the integrity of the germ line, mechanisms act to suppress the accumulation of transgenerational damage to the genome or epigenome. Loss of germ cell immortality can result from mutations that disrupt the small RNA-mediated silencing pathway that helps to protect the integrity of the epigenome. Here we report for the first time that theC. elegansprotein phosphatase GSP-2 that promotes core chromosome biology functions during meiosis is also required for germ cell immortality. Specifically, we identified a partial loss of function allele ofgsp-2that exhibits defects in meiotic chromosome segregation and is also dysfunctional for transgenerational small RNA-mediated genome silencing. Our results are consistent with a known role ofDrosophilaProtein Phosphatase 1 in heterochromatin silencing, and point to a meiotic phosphatase function that is relevant to germ cell immortality, conceivably related to its roles in chromosome pairing or sister chromatid cohesion.
miRNAs in platelet-poor blood plasma and purified RNA are highly stable: a confirmatory study
Authors: Muth Dillon C. , Powell Bonita H. , Zhao Zezhou , Witwer Kenneth W.
Published: March 2018

The relative stability of microRNAs (miRNAs) as compared with other RNA molecules has been confirmed in many contexts. When bound to Argonaute (AGO) proteins, miRNAs are protected from degradation, even when released into the extracellular space in ribonucleoprotein complexes, and with or without the protection of membranes in extracellular vesicles (EVs). Purified miRNAs also appear to present less of a target for degradation than other RNAs. Although miRNAs are by no means immune to degradation, biological samples subjected to prolonged incubation at room temperature, multiple freeze/thaws, or collection in the presence of inhibitors like heparin, can typically be remediated or used directly for miRNA measurements. Here, we provide additional confirmation of early, well validated findings on miRNA stability and detectability. Our data also suggest that inadequate depletion of platelets from plasma may explain the occasional report that freeze-thaw cycles can adversely affect plasma miRNA levels. Overall, the repeated observation of miRNA stability is again confirmed.
Spinocerebellar ataxia type 11-associated alleles of Ttbk2 dominantly interfere with ciliogenesis and cilium stability
Authors: Bowie Emily , Norris Ryan , Anderson Kathryn V. , Goetz Sarah C.
Published: March 2018

Spinocerebellar ataxia type 11 (SCA11) is a rare, dominantly inherited human ataxia characterized by atrophy of Purkinje neurons in the cerebellum. SCA11 is caused by mutations in the gene encoding the Serine/Threonine kinase Tau tubulin kinase 2 (TTBK2) that result in premature truncations of the protein. We previously showed that TTBK2 is a key regulator of the assembly of primary cilia in vivo. However, the mechanisms by which the SCA11-associated mutations disrupt TTBK2 function, and whether they interfere with ciliogenesis were unknown. In this work, we present evidence that SCA11-associated mutations are dominant negative alleles and that the resulting truncated protein (TTBK2SCA11) interferes with the function of full length TTBK2 in mediating ciliogenesis. A Ttbk2 allelic series revealed that upon partial reduction of full length TTBK2 function, TTBK2SCA11 can interfere with the activity of the residual wild-type protein to decrease cilia number and interrupt cilia-dependent Sonic hedgehog (SHH) signaling. Our studies have also revealed new functions for TTBK2 after cilia initiation in the control of cilia length, trafficking of a subset of SHH pathway components, including Smoothened (SMO), and cilia stability. These studies provide a molecular foundation to understand the cellular and molecular pathogenesis of human SCA11, and help account for the link between ciliary dysfunction and neurodegenerative diseases.

Author Summary

Defects in primary cilia structure and function are linked to a number of recessive genetic disorders, now collectively referred to as ciliopathies. Most of the characteristics of these disorders arise from disruptions to embryonic development, with the requirements for primary cilia in adult tissues being less well-defined. We previously showed that a kinase associated with an adult-onset neurodegenerative condition is required for cilium assembly and ciliary signaling during development. Here, we show that the human disease-associated mutations act as mild dominant negatives, interfering with the function of the full length protein in cilia formation and ciliary signaling.