bluuebunny/crossref_metadata_2025 huggingface dataset:
A flattening oxygen consumption trajectory phenotypes disease severity and poor prognosis in patients with heart failure with reduced, mid‐range, and preserved ejection fraction
Authors: Popovic Dejana , Arena Ross , Guazzi Marco
Published: February 2018

Background

In heart failure (HF), a flattening oxygen consumption (VO2) trajectory during cardiopulmonary exercise test (CPET) reflects an acutely compromised cardiac output. We hypothesized that a flattening VO2 trajectory is helpful in phenotyping disease severity and prognosis in HF with either reduced (HFrEF), mid‐range (HFmrEF), or preserved (HFpEF) ejection fraction.

Methods and results

Overall, 319 HF patients (198 HFrEF, 80 HFmrEF, and 41 HFpEF) underwent CPET. A flattening VO2 trajectory was tracked and defined as an inflection of VO2 linearity as a function of work rate with a second slope downward inflection >35% extent of the first one. Peak VO2, the minute ventilation/carbon dioxide production (VE/VCO2) slope, and the presence of exercise oscillatory ventilation (EOV) were also determined. Pulmonary artery systolic pressure (PASP) and tricuspid annular plane systolic excursion (TAPSE) were measured by echocardiography. A flattening VO2 occurred in 92 patients (28.8%). PASP and TAPSE at rest were significantly higher and lower (P < 0.001), respectively. The primary outcome was the combination of all‐cause death, heart transplantation and left ventricular assist device implantation. The secondary outcome was the primary outcome plus hospitalization for cardiac reasons. In the multivariate model including peak VO2, VE/VCO2 slope, EOV and VO2 trajectory, a flattening VO2 trajectory and EOV were retained in the regression for primary (X2 = 35.78, and 36.36, respectively; P < 0.001) and secondary (X2 = 12.45 and 47.91, respectively; P < 0.001) outcomes.

Conclusions

Results point to a flattening VO2 trajectory as a likely new and strong predictor of events in HF with any ejection fraction. Given the relation of right‐sided cardiac dysfunction to pulmonary hypertension, this oxygen pattern might suggest a real‐time decrease in pulmonary blood flow to the left heart.
Anion Selectivity of Layered Double Hydroxides: Effects of Crystallinity and Charge Density
Authors: Hibino Toshiyuki
Published: February 2018

Layered double hydroxides (LDHs) have long been thought to have low selectivity for NO3–. In contrast, it has recently been reported that LDHs with certain compositions show high selectivity for NO3–. The reason for the high selectivity has been unclear, although the ion sieve effect has been proposed as a possible mechanism. Moreover, small LDHs have been reported to show good anion exchanging ability. Given this background, a systematic study was conducted using Mg‐Al LDHs with two different crystallinities. High‐crystallinity LDHs with lager particle sizes clearly showed selectivity changes that depended on the Mg/Al molar ratio, compared with low‐crystallinity LDHs with smaller particle sizes. When the Mg/Al ratio increased, selectivity of high‐crystallinity LDHs for SO42– and F– decreased, whereas that for NO3– increased. In the case of F–, the diameter of which is smaller than the height of the flat orientation of NO3–, this result indicates that an ion sieve effect is not the only factor that determines selectivity. Other factors, such as the interactions of NO3– with the interlayer surface and with interlayer water, may also be involved.
Retracted: Comparative study of cyto‐ and genotoxic potential with mechanistic insights of tungsten oxide nano‐ and microparticles in lung carcinoma cells
Authors: Chinde Srinivas , Poornachandra Y. , Panyala Archana , Kumari Srinivas Indu , Yerramsetty Suresh , Adicherla Harikrishna , Grover Paramjit
Published: February 2018

The exigency of semiconductor and super capacitor tungsten oxide nanoparticles (WO3 NPs) is increasing in various sectors. However, limited information on their toxicity and biological interactions are available. Hence, we explored the underlying mechanisms of toxicity induced by WO3 NPs and their microparticles (MPs) using different concentrations (0–300 μg ml–1) in human lung carcinoma (A549) cells. The mean size of WO3 NPs and MPs by transmission electron microscopy was 53.84 nm and 3.88 μm, respectively. WO3 NPs induced reduction in cell viability, membrane damage and the degree of induction was size‐ and dose‐dependent. There was a significant increase in the percentage tail DNA and micronuclei formation at 200 and 300 μg ml–1 after 24 hours of exposure. The DNA damage induced by WO3 NPs could be attributed to increased oxidative stress and inflammation through reactive oxygen species generation, which correlated with the depletion of reduced glutathione content, catalase and an increase in malondialdehyde levels. Cellular uptake studies unveiled that both the particles were attached/surrounded to the cell membrane according to their size. In addition, NP inhibited the progression of the cell cycle in the G2/M phase. Other studies such as caspase‐9 and ‐3 and Annexin‐V‐fluorescein isothiocyanate revealed that NPs induced intrinsic apoptotic cell death at 200 and 300 μg ml–1 concentrations. However, in comparison to NPs, WO3 MPs did not incite any toxic effects at the tested concentrations. Under these experimental conditions, the no‐observed‐significant‐effect level of WO3 NPs was determined to be ≤200 μg ml–1 in A549 cells.
Supereulerian bipartite digraphs
Authors: Zhang Xindong , Liu Juan , Wang Lan , Lai Hong‐Jian
Published: February 2018

A digraph D is supereulerian if D has a spanning closed ditrail. Bang‐Jensen and Thomassé conjectured that if the arc‐strong connectivity of a digraph D is not less than the independence number , then D is supereulerian. A digraph is bipartite if its underlying graph is bipartite. Let be the size of a maximum matching of D. We prove that if D is a bipartite digraph satisfying , then D is supereulerian. Consequently, every bipartite digraph D satisfying is supereulerian. The bound of our main result is best possible.
Tight lower bounds on the matching number in a graph with given maximum degree
Authors: Henning Michael A. , Yeo Anders
Published: February 2018

Let. We prove the following three bounds for the matching number,, of a graph,G, of ordernsizemand maximum degree at mostk.

Ifkis odd, then.

Ifkis even, then.

Ifkis even, then.

In this article, we actually prove a slight strengthening of the above for which the bounds are tight for essentially all densities of graphs.

The above three bounds are in fact powerful enough to give a complete description of the setof pairsof real numbers with the following property. There exists a constantKsuch thatfor every connected graphGwith maximum degree at most k, wherenandmdenote the number of vertices and the number of edges, respectively, inG. We show thatis a convex set. Further, ifkis odd, thenis the intersection of two closed half‐spaces, and there is exactly one extreme point of, while ifkis even, thenis the intersection of three closed half‐spaces, and there are precisely two extreme points of.
Resonant broadband stimulated Raman scattering in myoglobin
Authors: Ferrante C. , Batignani G. , Fumero G. , Pontecorvo E. , Virga A. , Montemiglio L. C. , Cerullo G. , Vos M. H. , Scopigno T.
Published: February 2018

Spontaneous Raman is a well‐established tool to probe molecular vibrations. Under resonant conditions, it is a largely used method for characterizing the structure of heme‐proteins. In recent years, advances in pulsed laser sources allowed to explore vibrational features with complex techniques based on nonlinear optical interactions, among which is stimulated Raman scattering (SRS). Building on its combined spectral–temporal resolutions and high chemical sensitivities, SRS has been largely applied as a probe for ultrafast, time‐resolved studies, as well as an imaging technique in biological systems. By using a frequency tunable, narrowband pump pulse jointly with a femtosecond white light continuum to initiate the SRS process, here we measure the Raman spectrum of a prototypical heme‐protein, namely deoxy myoglobin, under two different electronic resonances. The SRS results are compared with the spontaneous Raman spectra, and the relative advantages, such as the capability of our experimental approach to provide an accurate mapping of Raman excitation profiles, are discussed.
Cover Image, Volume 98, Issue 4
Authors: Xie Fan , Wang Shaoyun , Zhang Li , Wu Jinhong , Wang Zhengwu
Published: February 2018

The cover image, by Fan Xie et al., is based on the Research Article Investigating inhibitory activity of novel synthetic sericin peptide on α‐d‐glucosidase: kinetics and interaction mechanism study using a docking simulation, DOI: 10.1002/jsfa.8620.

image
The impact of lignin downregulation on alfalfa yield, chemical composition, and in vitro gas production
Authors: Getachew Girma , Laca Emilio A , Putnam Daniel H , Witte Dave , McCaslin Mark , Ortega Kara P , DePeters Edward J
Published: February 2018

BACKGROUND

Lignin is a complex, phenolic polymer found in plant cell walls that is essential for mechanical support, water and mineral transport, and defense in vascular plants. Over ten different enzymes play a role in the synthesis of lignin in plants. Suppression of any one enzyme or combinations of these enzymes may change the concentration and composition of lignin in the genetically transformed plants. Two lines of alfalfa that were downregulated for caffeoyl coenzyme A O‐methyltransferase were used to assess the impact of lignin downregulation on chemical composition and fermentation rate and extent using an in vitro gas production technique. A total of 64 samples consisting of two reduced lignin (RL) and two controls (CL), four field replicates, two cutting intervals (CIs; 28 and 35 days), and two cuts (Cut‐1 and Cut‐3) were used.

RESULTS

No differences were detected in yield, crude protein, neutral detergent fiber (aNDF), and acid detergent fiber between the lines when harvested at the 28‐day CI. The acid detergent lignin (ADL) concentration in RL alfalfa lines was significantly (P < 0.001) lower than in the CL. In alfalfa harvested at the 35‐day CI, the RL alfalfa resulted in lower (P < 0.001) yield than CL. RL alfalfa lines had 24% and 22% lower (P < 0.001) ADL in Cut‐1 and Cut‐3 respectively than CL lines. The in vitro dry matter digestibility and aNDF digestibility (both as determined by the near‐infrared reflectance method) were greater (P < 0.001) in RL than in CL lines harvested at the 35‐day CI. In alfalfa harvested at the 35‐day CI, extent of in vitro gas production and metabolizable energy content were greater in RL than in CL alfalfa. RL lines had 3.8% indigestible aNDF per unit ADL, whereas CL had 3.4% (P < 0.01). The positive effect of lignin downregulation was more pronounced when intervals between harvests were longer (35‐day CI compared with the 28‐day CI).

CONCLUSION

Lignin downregulation in alfalfa offers an opportunity to extend harvesting time (CI) for higher yield without compromising the nutritional quality of the alfalfa forage for dairy and livestock feeding. However, the in vitro results reported here warrant further study using in vivo methods. © 2018 Society of Chemical Industry
Postmetastasis survival in high‐grade extremity osteosarcoma: A retrospective analysis of prognostic factors in 126 patients
Authors: Kim Wanlim , Han Ilkyu , Lee Jong S. , Cho Hwan S. , Park Jong W. , Kim Han‐Soo
Published: February 2018

Background and Objectives

Prognostic factors predictive of postmetastasis survival (PMS) in metastatic osteosarcoma are poorly understood. Our aims were to evaluate PMS in patients with high‐grade osteosarcoma in extremities, and to identify prognostic factors related to PMS.

Methods

A retrospective review of data for 126 patients with metastatic osteosarcoma was conducted. The study population consisted of 70 men and 56 women, with a mean age of 21 years (range: 4‐75 years). The mean postmetastasis follow‐up period was 37 months (range: 1‐245 months).

Results

The 5‐year PMS rate was 31% and median PMS duration was 22 months. In the multivariate analyses, no metastasectomy (P < 0.001), local recurrence prior to metastasis (P = 0.016), extrapulmonary metastasis (P = 0.006), and poor histologic response to preoperative chemotherapy (P = 0.047) were significant poor prognostic factors. The 5‐year PMS without any negative prognostic factor was 60.2%; with one factor, 31.6%; and with more than two factors, 3.6%.

Conclusions

PMS in osteosarcoma patients was influenced by primary tumor‐related factors such as histologic response to chemotherapy, as well as metastasis‐related factors such as complete metastasectomy and metastasis site. A certain group of patients without such poor prognostic factors could be cured even after the development of metastasis.
Pre‐operative core muscle index in combination with hypoalbuminemia is associated with poor prognosis in advanced ovarian cancer
Authors: Conrad Lesley B. , Awdeh Haitham , Acosta‐Torres Stefany , Conrad Steven A. , Bailey April A. , Miller David S. , Lea Jayanthi S.
Published: February 2018

Background and Objectives

Age and frailty have been correlated with poor clinical outcomes in cancer. Core muscle index (CMI) and nutritional status are integral in assessing frailty. We explored the effect of pre‐operative serum albumin and body composition on clinical outcomes in patients with epithelial ovarian cancer (EOC).

Methods

We identified stage III‐IV EOC patients undergoing primary cytoreductive surgery from 2007 to 2015. Data were abstracted from medical records. Body composition measurements were obtained from pre‐operative imaging. Psoas muscle cross‐sectional area was normalized to height2 to determine CMI. Sarcopenia was defined as CMI below the population mean. The influence of sarcopenia on short‐term morbidity was evaluated. Relationships among body composition measurements and albumin were assessed with Spearman correlations. Patient characteristics and body composition measurements between patients with and without sarcopenia were compared with parametric and non‐parametric statistical methods. Kaplan‐Meier survival curves were compared using log‐rank.

Results

102 women met inclusion criteria. Sarcopenia correlated with albumin (P = 0.0002). Sarcopenia was not associated with short‐term morbidity or time to recurrence. Sarcopenia was associated with nearly a fourfold increased risk of death when hypoalbuminemia was present (P = 0.02).

Conclusions

Pre‐operative sarcopenia in combination with hypoalbuminemia was associated with significantly worse survival.
Olfactory epithelium: Cells, clinical disorders, and insights from an adult stem cell niche
Authors: Choi Rhea , Goldstein Bradley J.
Published: February 2018

Disorders causing a loss of the sense of smell remain a therapeutic challenge. Basic research has, however, greatly expanded our knowledge of the organization and function of the olfactory system. This review describes advances in our understanding of the cellular components of the peripheral olfactory system, specifically the olfactory epithelium in the nose. The article discusses recent findings regarding the mechanisms involved in regeneration and cellular renewal from basal stem cells in the adult olfactory epithelium, considering the strategies involved in embryonic olfactory development and insights from research on other stem cell niches. In the context of clinical conditions causing anosmia, the current view of adult olfactory neurogenesis, tissue homeostasis, and failures in these processes is considered, along with current and future treatment strategies.

Level of Evidence

NA
Large but variable methane production in anoxic freshwater sediment upon addition of allochthonous and autochthonous organic matter
Authors: Grasset Charlotte , Mendonça Raquel , Villamor Saucedo Gabriella , Bastviken David , Roland Fabio , Sobek Sebastian
Published: February 2018

An important question in the context of climate change is to understand how CH4 production is regulated in anoxic sediments of lakes and reservoirs. The type of organic carbon (OC) present in lakes is a key factor controlling CH4 production at anoxic conditions, but the studies investigating the methanogenic potential of the main OC types are fragmented. We incubated different types of allochthonous OC (alloOC; terrestrial plant leaves) and autochthonous OC (autoOC; phytoplankton and two aquatic plants species) in an anoxic sediment during 130 d. We tested if (1) the supply of fresh alloOC and autoOC to an anoxic refractory sediment would fuel CH4 production and if (2) autoOC would decompose faster than alloOC. The addition of fresh OC greatly increased CH4 production and the δ13C‐CH4 partitioning indicated that CH4 originated exclusively from the fresh OC. The large CH4 production in an anoxic sediment fueled by alloOC is a new finding which indicates that all systems with anoxic conditions and high sedimentation rates have the potential to be CH4 emitters. The autoOC decomposed faster than alloOC, but the total CH4 production was not higher for all autoOC types, one aquatic plant species having values as low as the terrestrial leaves, and the other one having values as high as phytoplankton. Our study is the first to report such variability, suggesting that the extent to which C fixed by aquatic plants is emitted as greenhouse gases or buried as OC in sediment could more generally differ between aquatic vegetation types.
Riemann boundary value problem on nonrectifiable curves for certain Beltrami equations
Authors: Katz D. B. , Kats B. A.
Published: February 2018

In this paper, we obtain a Cauchy‐type integral representation to solve certain Beltrami equations and apply it for research of the Riemann boundary value problem for that equations on nonrectifiable contours. While more or less studied for piecewise smooth contours, for the case of nonrectifiable curve, this is a pioneer result. There is only one relatively simple type of Beltrami equation that is solved under such condition (see below). Our next goal is to achieve solutions for more types of the Beltrami equations on nonrectifiable curves.
A numerical study on the estimation of the stable size distribution for a cell population balance model
Authors: Abia Luis M. , Angulo Óscar , López‐Marcos Juan Carlos , López‐Marcos Miguel Ángel
Published: February 2018

The presence of a steady‐state distribution is an important issue in the modelization of cell populations. In this paper, we analyse, from a numerical point of view, the approach to the stable size distribution for a size‐structured balance model with an asymmetric division rate. To this end, we introduce a second‐order numerical method on the basis of the integration along the characteristic curves over the natural grid. We validate the interest of the scheme by means of a detailed analysis of convergence.
An electrically small antenna for nearfield biomedical applications
Authors: Patel Riki , Upadhyaya Trushit
Published: February 2018

The size of electrically small antennas is quite lesser than wavelength, typically in range of λ/10 or lesser. These antennas offer vital application in space constraint environment such as small biomedical equipment or passive radio frequency identification applications. The antenna having size of 20 mm × 15 mm (0.16λ × 0.125λ) is proposed. Slots on the patch are engineered for target resonance and bandwidth enhancement. The antenna offers bandwidth in order of 7.6% and product ka in order of 0.62. The prototype is fabricated and measured results are presented, which are well suited for ISM band applications.
A novel sensor using VHF zigzag‐slotted leaky coaxial cable for intruder localization
Authors: Guan Qiao , Chen Chongchong , He Chuanxia
Published: February 2018

The sensors used in the field of traditional security warfare are often constrained by environmental factors such as weather, light and terrain. In order to solve this problem, a new perimeter intrusion detection system sensor is urgently needed. Based on the theory of the array antenna, leaky coaxial cable (LCX) with periodic zigzag‐slotted outer conductor is designed, its coupling loss is simulated by the software Ansoft HFSS. For evaluating the coupling loss of the LCX comprehensively, the LCX is simulated and measured in four directions, the measured results of coupling loss are 64.1 dB, 62.6 dB, 64.3 dB, 57.2 dB in rotary, horizontal, vertical, and radial direction, respectively. With the research on LCX wireless sensing techniques, a novel LCX sensor is designed and a new approach of localization is put forward. When the intruder enters into the surveillance, the proposed LCX sensor can achieve to detect and locate the intruder by emitting the LFM pulse signal whose working frequency is in VHF, pulse compression is used to improve the detection performance of the intrusion detection system (IDS). The positioning accuracy of the IDS is within 0.8 m, and the range distance is 6.64 m.
A circularly polarized wideband high gain patch antenna for wireless power transfer
Authors: Di Carlo C. A. , Di Donato L. , Mauro G. S. , La Rosa R. , Livreri P. , Sorbello G.
Published: February 2018

This article deals with a microstrip patch antenna working at 868 MHz, suitable for the radio frequency wireless power transfer and energy harvesting applications. The proposed monolithic antenna is compact, lightweight and it is printed on a thick substrate in order to maximize the total gain in the broadside direction. The antenna radiates at 868 MHz with a fractional impedance bandwidth of 5% and it shows a gain of 4.14 dB.
Miniaturization of segmented loop antenna by reducing the number of segments and adding stubs
Authors: Kang Do‐Gu , Lee Hojoo , Choi Jaehoon
Published: February 2018

A wideband low‐profile miniaturized segmented loop antenna is proposed in this letter. The antenna consists of a segmented loop comprising 4 segments with stubs, a shorting strip, and a patch element. The antenna is miniaturized by reducing the number of segments and by adding stubs. At 956 MHz, the antenna has an improved impedance matching by using the shorting strip, and an omnidirectional radiation due to coupling between the overlapping areas of the segments placed on the top and bottom of the substrate. In the high frequency band, the antenna has a wide −10 dB reflection coefficient bandwidth covering 3700 MHz WiMAX, 5200 MHz WLAN, and 5800 MHz WLAN with a quasi‐omnidirectional radiation characteristic.
Dielectric resonator based circularly polarized MIMO antenna with polarization diversity
Authors: Das Gourab , Sharma Anand , Gangwar Ravi Kumar
Published: February 2018

In this article, a dual sense dual port circularly polarized cylindrical dielectric resonator antenna (CDRA) is discussed for multiple input multiple output (MIMO) applications. Three exclusive features of the proposed radiator are (i) modified circule‐shaped aperture generates circular polarization for both the ports; (ii) proposed structure can generate left‐hand circular polarization (LHCP) and right‐hand circular polarization (RHCP) that depends on feed port selection; (iii) by introducing the concept of polarization diversity (LHCP/RHCP) and defected ground structure (DGS) between the two radiator, isolation is improved. A prototype of proposed radiator is fabricated and experimentally tested to authenticate the simulated results. The fractional impedance bandwidth for port 1 and port 2 is 15.1% and 14.9%, respectively. Within the targeted operating band, the isolation is better than −25 dB between the ports. Different diversity performance parameters are also calculated and they are also lie within their optimum limit. The proposed MIMO antenna is suitable for WLAN (5.5/5.8 GHz) applications.
Permittivity sensing and measurement with novel split ball resonator using E‐field perturbation technique
Authors: Hayat Touseef , Ejaz Tahir , Naveed Muhammad , Zaidi Tahir , Rahman Hamood‐Ur‐
Published: February 2018

A method of designing low‐loss split‐ball resonator (SBR) for permittivity sensing and measurement at microwave frequencies using resonant perturbation technique is being presented. SBR geometry strengthens electric field in the capacitive region by confining greater resonant energy in the split. Enhanced sensitivity by virtue of potent electric field enabled us to sense and measure permittivity of common polar solvents (methanol and ethanol). Comparative analysis, eigenmode simulations, and empirical measurements exhibited improved sensitivity of SBR. The solution of Maxwell equations for boundary conditions before and after material perturbation produce expressions, which lead to permittivity evaluation.
Placement of optical phase conjugation in WDM systems to suppress FWM
Authors: Kaur Jaspreet , Singh Hardeep
Published: February 2018

In this work, a suppression method of Four wave mixing (FWM) is proposed using optical phase conjugation (OPC) and different placements of OPCs are also investigated. Moreover, comparison of the placements of OPC in two different cases has been done and compared with conventional wavelength division multiplexing system in terms of Q factor, bit error rate (BER), and induced FWM. Analysis has been done at different link lengths, launched powers levels, and laser line widths. It is observed that placement of OPC after laser source performs exceptionally well and suppresses FWM with ease of maintenance.
A simple penta‐band circularly polarized cpw‐fed monopole‐patch antenna covering six commercial application bands
Authors: Tuan Le Tu , Tran Huy Hung , Park Hyun Chang
Published: February 2018

This letter presents a very simple coplanar waveguide (CPW)‐fed penta‐band circularly polarized (CP) antenna for 1.6 GHz GPS, 3.45 GHz WiMAX, 2.45/5.3/5.8 GHz WLAN and 4.2 GHz radio altimeter applications. The antenna is composed of a monopole, a semi‐circular patch, and a slit etched in the ground plane. The final design with an overall size of 70 × 53 × 1.52 mm3 has yielded measured 3 dB axial‐ratio (AR) bandwidths of 9.7% (1.48‐1.63 GHz), 37.3% (2.38‐3.47 GHz), 5.1% (4.21‐4.43 GHz), 3.0% (5.25‐5.41 GHz), and 3.3% (5.69‐5.88 GHz). Measured −10 dB impedance bandwidths of the proposed antenna are 109.3% (1.31‐4.47 GHz) and 28.5% (5.05‐6.73 GHz) which fully cover all the AR bands.
Design and fabrication of a tunable microstrip lowpass‐bandpass diplexer for telecommunication applications
Authors: Moloudian Gholamhosein , Dousti Massoud , Ebrahimi Asghar
Published: February 2018

In this article, a well‐defined tunable lowpass‐bandpass (LP‐BP) diplexer with proper performance is provided using stepped impedance lines and square‐looped resonators for telecommunication applications. Our proposed scheme is the first tunable LP filter BP filter diplexer that provides good results. The proposed diplexer has the ability to adjust the cut‐off frequency of the lowpass filter (LPF) and to adjust the center frequency of the bandpass filter (BPF). The varactor diodes in reverse bias were used to make the proposed diplexer tunable. The tuning range of the cut‐off frequency for the LPF is from 0.46 to 0.96 GHz. An important feature of the LPF is a high suppression factor of about 45 dB in the stopband and a sharp roll‐off rate (ROF). The adjustability of the BPF part for the first channel ranges from 1.8 to 2.4 GHz; for the second channel, the ranges from 2.8 to 3.2 GHz, and for the third channel, the ranges from 5.2 to 5.6 GHz. The proposed diplexer is designed, simulated, fabricated, and finally tested and measured. The isolation between the output ports is about 34 dB. Simulation results are in good agreement with the test results and the measured values.
Internal breast dosimetry in mammography: Experimental methods and Monte Carlo validation with a monoenergetic x‐ray beam
Authors: Fedon Christian , Caballo Marco , Longo Renata , Trianni Annalisa , Sechopoulos Ioannis
Published: February 2018

Purpose

To investigate the performance, such as energy dependence and sensitivity, of thermoluminescent dosimeters (TLD), metal oxide semiconductor field‐effect transistor dosimeters (MOSFET), and GafChromic™ films, and to validate the estimates of local dose deposition of a Monte Carlo (MC) simulation for breast dosimetry applications.

Methods

Experimental measurements were performed using a monoenergetic beam at the ELETTRA synchrotron radiation light source (Trieste, Italy). The three types of dosimeters were irradiated in a plane transversal to the beam axis and calibrated in terms of air kerma. The sensitivity of MOSFET dosimeters and GafChromic™ films was evaluated in the range of 18–28 keV. Three different calibration curves for the GafChromic™ films were tested (logarithmic, rational, and exponential functions) to evaluate the best‐fit curve in the dose range of 1–20 mGy. Internal phantom dose measurements were performed at 20 keV for four different depths (range 0–3 cm, with 1 cm steps) using a homogeneous 50% glandular breast phantom. A GEANT4 MC simulation was modified to match the experimental setup. Thirty sensitive volumes, on the axial‐phantom plane were included at each depth in the simulation to characterize the internal dose variation and compare it to the experimental TLD and MOSFET measurements. Experimental 2D dose maps were obtained with the GafChromic™ films and compared to the simulated 2D dose distributions estimated with the MC simulations.

Results

The sensitivity of the MOSFET dosimeters and GafChromic™ films increased with x‐ray energy, by up to 37% and 48%, respectively. Dose–response curves for the GafChromic™ film result in an uncertainty lower than 5% above 6 mGy, when a logarithmic relationship is used in the dose range of 1–10 mGy. All experimental values fall within the experimental uncertainty and a good agreement (within 5%) is found against the MC simulation. The dose decreased with increasing phantom depth, with the reduction being ~80% after 3 cm. The uncertainty of the empirical measurements makes the experimental values compatible with a flat behavior across the phantom slab for all the investigated depths, while the MC points to a dose profile with a maximum toward the center of the phantom.

Conclusions

The calibration procedures and the experimental methodologies proposed lead to good accuracy for internal breast dose estimation. In addition, these procedures can be successfully applied to validate MC codes for breast dosimetry at the local dose level. The agreement among the experimental and MC results not only shows the correctness of the empirical procedures used but also of the simulation parameters.
Collagen VI‐related myopathy: Expanding the clinical and genetic spectrum
Authors: Kim Soo Yeon , Kim Woo Joong , Kim Hyuna , Choi Sun Ah , Lee Jin Sook , Cho Anna , Jang Se Song , Lim Byung Chan , Kim Ki Joong , Kim Jong‐Il , Hahn Si Houn , Chae Jong‐Hee
Published: February 2018

Introduction: We aimed to analyze the clinical and genetic characteristics of collagen VI‐related myopathy. Methods: We analyzed the clinical course and mutation spectrum in patients with collagen VI gene mutations among our congenital muscular dystrophy cohort. Results: Among 24 patients with mutations in collagen VI coding genes, 13 (54.2%) were categorized as Ullrich type, and 11 (45.8%) as non‐Ullrich type. Congenital orthopedic problems were similarly observed in both types, yet multiple joint contractures were found only in the Ullrich type. Clinical courses and pathology findings varied between patients. Mutations in COL6A1, COL6A2, and COL6A3 were found in 15 (65%), 3 (13%), and 5 (22%) patients, respectively, without genotype–phenotype association. Five novel variants were detected. Discussion: We verified clinical heterogeneity of collagen VI‐related myopathy, which emphasizes the importance of genetic testing. Genotype–phenotype association or early predictors for progression were not identified. Multiple joint contractures predict rapid deterioration. Muscle Nerve 58: 381–388, 2018
Quantitative MRI in murine radiation‐induced rectocolitis: comparison with histopathological inflammation score
Authors: Zappa Magaly , Doblas Sabrina , Cazals‐Hatem Dominique , Milliat Fabien , Lavigne Jérémy , Daniel Fanny , Jallane Abelhak , Garteiser Philippe , Vilgrain Valérie , Ogier‐Denis Eric , Van Beers Bernard E.
Published: February 2018

Murine radiation‐induced rectocolitis is considered to be a relevant animal model of gastrointestinal inflammation. The purpose of our study was to compare quantitative MRI and histopathological features in this gastrointestinal inflammation model.

Radiation rectocolitis was induced by localized single‐dose radiation (27 Gy) in Sprague‐Dawley rats. T2‐weighted, T1‐weighted and diffusion‐weighted MRI was performed at 7 T in 16 rats between 2 and 4 weeks after irradiation and in 10 control rats. Rats were sacrificed and the histopathological inflammation score of the colorectal samples was assessed.

The irradiated rats showed significant increase in colorectal wall thickness (2.1 ± 0.3 mm versus 0.8 ± 0.3 mm in control rats, P < 0.0001), normalized T2 signal intensity (4 ± 0.8 versus 2 ± 0.4 AU, P < 0.0001), normalized T1 signal intensity (1.4 ± 0.1 versus 1.1 ± 0.2 AU, P = 0.0009) and apparent and pure diffusion coefficients (ADC and D) (2.06 × 10−3 ± 0.34 versus 1.51 × 10−3 ± 0.23 mm2/s, P = 0.0004, and 1.97 × 10−3 ± 0.43 mm2/s versus 1.48 × 10−3 ± 0.29 mm2/s, P = 0.008, respectively). Colorectal wall thickness (r = 0.84, P < 0.0001), normalized T2 signal intensity (r = 0.85, P < 0.0001) and ADC (r = 0.80, P < 0.0001) were strongly correlated with the histopathological inflammation score, whereas normalized T1 signal intensity and D were moderately correlated (r = 0.64, P = 0.0006, and r = 0.65, P = 0.0003, respectively).

High‐field MRI features of single‐dose radiation‐induced rectocolitis in rats differ significantly from those of control rats. Quantitative MRI characteristics, especially wall thickness, normalized T2 signal intensity, ADC and D, are potential markers of the histopathological inflammation score.
Position matters: Validation of medicare hospital claims for myocardial infarction against medical record review in the atherosclerosis risk in communities study
Authors: Bush Montika , Stürmer Til , Stearns Sally C. , Simpson Ross J. , Brookhart M. Alan , Rosamond Wayne , Kucharska‐Newton Anna M.
Published: February 2018

Purpose

The objectives of this study were to investigate sensitivity and specificity of myocardial infarction (MI) case definitions using multiple discharge code positions and multiple diagnosis codes when comparing administrative data to hospital surveillance data.

Methods

Hospital surveillance data for ARIC Study cohort participants with matching participant ID and service dates to Centers for Medicare and Medicaid Services (CMS) hospitalization records for hospitalizations occurring between 2001 and 2013 were included in this study. Classification of Definite or Probable MI from ARIC medical record review defined “gold standard” comparison for validation measures. In primary analyses, an MI was defined with ICD9 code 410 from CMS records. Secondary analyses defined MI using code 410 in combination with additional codes.

Results

A total of 25 549 hospitalization records met study criteria. In primary analysis, specificity was at least 0.98 for all CMS definitions by discharge code position. Sensitivity ranged from 0.48 for primary position only to 0.63 when definition included any discharge code position. The sensitivity of definitions including codes 410 and 411.1 were higher than sensitivity observed when using code 410 alone. Specificity of these alternate definitions was higher for women (0.98) than for men (0.96).

Conclusion

Algorithms that rely exclusively on primary discharge code position will miss approximately 50% of all MI cases due to low sensitivity of this definition. We recommend defining MI by code 410 in any of first 5 discharge code positions overall and by codes 410 and 411.1 in any of first 3 positions for sensitivity analyses of women.
Selective Etching of N‐Doped Graphene Meshes as Metal‐Free Catalyst with Tunable Kinetics, High Activity and the Origin of New Catalytic Behaviors
Authors: Dai Yunqian , Zhou Jie , Huang Chengqian , Gu Qing , Zeng Yi , Xu Wanlin , Meng Xiangyu , Fu Wanlin , Sun Yueming
Published: February 2018

New N‐doped reduced graphene oxide (N‐RGO) meshes are facile fabricated by selective etching of 3–5 nm nanopores, with controllable doping of N dopants at an ultrahigh N/C ratio up to 15.6 at%, from pristine graphene oxide sheets in one‐pot hydrothermal reaction. The N‐RGO meshes are illustrated to be an efficient metal‐free catalyst toward hydrogenation of 4‐nitrophenol, with new catalytic behaviors emerging in following three aspects: (i) tunable kinetics following pseudofirst order from commonly observed pseudozero order; (ii) strikingly improved activity with 26‐fold increased rate constant (1.0 s−1 g−1 L); (iii) no induction time required prior to reaction due to depressed back conversion, and dramatically decreased apparent activation energy (Ea) (17 kJ mol−1). The origin of these new catalytic properties can be assigned to the synergetic effects between graphitic N doping and structural defects arising from nanopores. Deeper understanding unveils that the concentration of graphitic N is inverse proportion to Ea, while the pyrrolic N has no impact on this reaction, and oxygenate groups hampers it. The porous nature allows the N‐RGO meshes to conduct catalyze reactions in continuous flow fashion.
Role of prophylactic azithromycin to reduce airway inflammation and mortality in a RSV mouse infection model
Authors: Mosquera Ricardo A. , De Jesus‐Rojas Wilfredo , Stark James M. , Yadav Aravind , Jon Cindy K. , Atkins Constance L. , Samuels Cheryl L. , Gonzales Traci R. , McBeth Katrina E. , Hashmi Syed S. , Garolalo Roberto , Colasurdo Giuseppe N.
Published: February 2018

Background

Respiratory syncytial virus (RSV) infection is an important cause of morbidity and mortality in vulnerable populations. Macrolides have received considerable attention for their anti‐inflammatory actions beyond their antibacterial effect. We hypothesize that prophylactic azithromycin will be effective in reducing the severity of RSV infection in a mouse model.

Methods

Four groups of BALB/c mice were studied for 8 days: Control (C), RSV‐infected (R), early prophylaxis with daily azithromycin from days 1 to 8, (E), and late prophylaxis with daily azithromycin from days 4 to 8 (L). Mice were infected with RSV on day 4, except for the control group. All groups were followed for a total of 8 days when bronchoalveolar lavage cell count and cytokines levels were measured. Mouse weight, histopathology, and mortality data were obtained.

Results

Prophylactic azithromycin significantly attenuated post‐viral weight loss between group R and both groups E and L (P = 0.0236, 0.0179, respectively). IL‐6, IL‐5, and Interferon‐Gamma were significantly lower in group L (P = 0.0294, 0.0131, and 0.0056, respectively) compared with group R. The total cell count was significantly lower for group L as compared with group R (P < 0.05). Mortality was only observed in group R (8%). Lung histology in the prophylactic groups showed diminished inflammatory infiltrates and cellularity when compared with group R.

Conclusion

Prophylactic azithromycin effectively reduced weight loss, airway inflammation, cytokine levels and mortality in RSV‐infected mice. These results support the rationale for future clinical trials to evaluate the effects of prophylactic azithromycin for RSV infection.
A Bayesian confirmatory factor model for multivariate observations in the form of two‐way tables of data
Authors: Chen Qiaolin , Sugar Catherine A. , Weiss Robert E.
Published: February 2018

Researchers collected multiple measurements on patients with schizophrenia and their relatives, as well as control subjects and their relatives, to study vulnerability factors for schizophrenics and their near relatives. Observations across individuals from the same family are correlated, and also the multiple outcome measures on the same individuals are correlated. Traditional data analyses model outcomes separately and thus do not provide information about the interrelationships among outcomes. We propose a novel Bayesian family factor model (BFFM), which extends the classical confirmatory factor analysis model to explain the correlations among observed variables using a combination of family‐member and outcome factors. Traditional methods for fitting confirmatory factor analysis models, such as full‐information maximum likelihood (FIML) estimation using quasi‐Newton optimization (QNO), can have convergence problems and Heywood cases (lack of convergence) caused by empirical underidentification. In contrast, modern Bayesian Markov chain Monte Carlo handles these inference problems easily. Simulations compare the BFFM to FIML‐QNO in settings where the true covariance matrix is identified, close to not identified, and not identified. For these settings, FIML‐QNO fails to fit the data in 13%, 57%, and 85%of the cases, respectively, while MCMC provides stable estimates. When both methods successfully fit the data, estimates from the BFFM have smaller variances and comparable mean‐squared errors. We illustrate the BFFM by analyzing data on data from schizophrenics and their family members.
Characterisation of Robust Combustion Catalyst from Aluminium Foil Waste
Authors: Osman Ahmed I. , Abu‐Dahrieh Jehad K. , McLaren Mathew , Laffir Fathima , Rooney David W.
Published: February 2018

Herein a robust and active combustion catalyst was prepared with three‐quarter (75 wt.%) of its composition derived from the aluminium foil waste and designated as 5Pd‐ACFL550. The prepared catalyst was characterised using X‐ray diffraction (XRD), Temperature‐programmed reduction (TPR), Bright‐field transmission electron microscopy (BF‐TEM), High angle annular dark field (HAADF), Fourier transform infrared‐pyridine (FTIR‐Pyridine) and X‐ray Photoelectron Spectroscopy (XPS) techniques and compared to the commercial equivalent (5Pd‐AC550). The catalyst 5Pd‐ACFL550 showed higher catalytic activity than that of 5Pd‐AC550 in the total methane oxidation reaction with T50% at 303 °C at Gas hourly space velocity (GHSV) of 100,000 mL g−1 h−1. Our approach opens doors for the preparation of robust cheap combustion catalyst from aluminium foil waste and demonstrates its application in the catalytic converters of natural gas vehicles (NGV‐vehicles) and other combustion applications. As a result, this can be opened up to a wider variety of application markets, including residential and automotive applications.
Theoretical Calculations of the Optical and Electronic Properties of Dithienosilole‐ and Dithiophene‐Based Donor Materials for Organic Solar Cells
Authors: Manzoor Farah , Iqbal Javed , Zara Zeenat , Eliasson Bertil , Mahr Muhammad Shabir , Ayub Khurshid
Published: February 2018

Six Acceptor‐Donor‐Acceptor (A−D−A) types molecules with dimethyl dithieno[3, 2‐b:2′,3′‐d]silole)−2,6‐diyl (DTS) (M1‐M3) and dimethyl cyclopenta [2, 1‐b;3,4‐b]‐dithiophene (CPDT) (M4‐M6) core flanged by different acceptor units through methylthiophene bridge are evaluated as donor materials for photovoltaic applications. The photovoltaic properties of M1‐M3 and M4‐M6 are compared with standard RaRc and Rb,Rd respectively. Geometry optimization was performed with CAM−B3LYP/6‐31G (d) level of theory. TD‐CAM−B3LYP has been employed for the estimation of excited state properties of the molecules. M1, M2, M3 and M4, M5, M6 symbolized suitable frontier molecular orbital's (FMO's) energy levels with broad absorption spectra. The electron withdrawing substituents impart red shift in absorption spectra along with good consistancy of designed donor molecules. Reorganization energies of donor molecules (M1‐M6) showed ideal properties of charge mobility. M1 and M4 illustrated lowest λe values as compared to λh, thus dictated that designed donor molecules are of good choice for their electron donating ability. Furthermore, M2 and M6 demonstrated shortest Eg of 3.7 and 3.72 eV among HOMO and LUMO energy levels.
Bis‐Tridentate‐Cyclometalated Ruthenium Complexes with Extended Anchoring Ligand and Their Performance in Dye‐Sensitized Solar Cells.
Authors: Aghazada Sadig , Zimmermann Iwan , Ren Yameng , Wang Peng , Nazeeruddin Mohammad Khaja
Published: February 2018

Ruthenium polypyridine complexes with six‐membered chelating rings have recently received significant attention due to their broad absorption spectra and outstanding photophysical characteristics. In this work we present the synthesis and characterization of three new heteroleptic bis‐tridentate cyclometalated ruthenium complexes, i. e. 1 a, 2 a, and 3 a, with donating and accepting ligands. Complexes 2 a and 3 a are coordinated with 2,6‐di(quinolin‐8‐yl)‐4‐methoxycarbonylpyridine (dqpCO2Me), and 1 a with 2,2’:6’,2’’‐terpyridine‐4’‐ethoxycarbonyl (tpyCO2Et) accepting ligands. Interestingly, the binding mode of the accepting ligand was found to differ in 3 a and 2 a. NMR spectra and single crystal XRD data reveal that in 3 a one of the quinolines of dqpCO2Me ligand is cyclometalated, while in 2 a the ligand coordinates in an expected fashion similar to tpyCO2Et. The ester groups in 1 a and 2 a were hydrolyzed to obtain sensitizers 1 and 2, which were used in dye‐sensitized solar cells (DSCs) and the device performance with both iodine‐ and cobalt‐based electrolytes was investigated. Complete 1H, 13C and 1H‐1H COSY NMR, and high‐resolution mass analyses of all complexes were conducted.
Ligand‐Free, Highly Dispersed NiOx Nanocrystal for Efficient, Stable, Low‐Temperature Processable Perovskite Solar Cells
Authors: He Jinjin , Bi Enbing , Tang Wentao , Wang Yanbo , Zhou Zhongmin , Yang Xudong , Chen Han , Han Liyuan
Published: February 2018

Inverted configuration perovskite solar cells containing a NiOx layer fabricated by using a low‐temperature process have yielded highly efficient, flexible devices. However, the instability of these devices has limited their commercial application. Here, we report high‐quality, ligand‐free NiOx nanocrystals, prepared directly through a facile organic solvent method, that form a stable ink when dispersed in an ethanol solvent. Rigid and flexible devices containing a NiOx layer (active area, 1.02 cm2) fabricated with this ink at low‐temperature achieved efficiencies of 18.49 and 15.89%, respectively. In addition, the devices retain 90% of their initial performance at 500 h in a damp‐heat test (85 °C and 85% relative humidity) due to there being less hydroxyl functional groups and H2O molecules on the NiOx surface, which degrade perovskite. Thus, we are able to successfully synthesize ligand‐free NiOx for the low‐temperature production of a high‐performance, stable perovskite solar cell.
How Much Data are Good Enough? Using Simulation to Determine the Reliability of Estimating POMR for Resource‐Constrained Settings
Authors: Marks Isobel H. , Fong Zhi Ven , Stapleton Sahael M. , Hung Ya‐Ching , Bababekov Yanik J. , Chang David C.
Published: February 2018

Introduction

Perioperative mortality rate (POMR) is a suggested indicator for surgical quality worldwide. Currently, POMR is often sampled by convenience; a data‐driven approach for calculating sample size has not previously been attempted. We proposed a novel application of a bootstrapping sampling technique to estimate how much data are needed to be collected to reasonably estimate POMR in low‐resource countries where 100% data capture is not possible.

Material and methods

Six common procedures in low‐ and middle‐income countries were analysed by using population database in New York and California. Relative margin of error by dividing the absolute margin of error by the true population rate was calculated. Target margin of error was ±50%, because this level of precision would allow us to detect a moderate‐to‐large effect size.

Results and discussion

Target margin of error was achieved at 0.3% sampling size for abdominal surgery, 7% for fracture, 10% for craniotomy, 16% for pneumonectomy, 26% for hysterectomy and 60% for C‐section. POMR may be estimated with fairly good reliability with small data sampling. This method demonstrates that it is possible to use a data‐driven approach to determine the necessary sampling size to accurately collect POMR worldwide.