bluuebunny/crossref_metadata_2025 huggingface dataset:
Inferring about individual drug and schizotypy effects on cognitive functioning in polydrug using mephedrone users before and after clubbing
Authors: Herzig Daniela A. , Brooks Rowan , Mohr Christine
Published: March 2013

Objective

Mephedrone has been recently made illegal in Europe, but little empirical evidence is available on its impact on human cognitive functions. We investigated acute and chronic effects of mephedrone consumption on drug‐sensitive cognitive measures, while also accounting for the influence of associated additional drug use and personality features.

Method

Twenty‐six volunteers from the general population performed tasks measuring verbal learning, verbal fluency and cognitive flexibility before and after a potential drug‐taking situation (pre‐clubbing and post‐clubbing at dance clubs, respectively). Participants also provided information on chronic and recent drug use, schizotypal (Oxford‐Liverpool Inventory of Feelings and Experiences) and depressive symptoms (Beck Depression Inventory), sleep pattern and premorbid IQ.

Results

We found that (i) mephedrone users performed worse than non‐users pre‐clubbing and deteriorated from the pre‐clubbing to the post‐clubbing assessment; (ii) pre‐clubbing cannabis and amphetamine (not mephedrone) use predicted relative cognitive attenuations; (iii) post‐clubbing, depression scores predicted relative cognitive attenuations; and (iv) schizotypy was largely unrelated to cognitive functioning, apart from a negative relationship between cognitive disorganisation and verbal fluency.

Conclusion

Results suggest that polydrug use and depressive symptoms in the general population negatively affect cognition. For schizotypy, only elevated cognitive disorganisation showed potential links to a pathological cognitive profile previously reported along the psychosis dimension. Copyright © 2013 John Wiley & Sons, Ltd.
Visual and Digital Texts
Authors: Ash Gwynne Ellen
Published: March 2013

This column provides reviews of adolescent and adult visual and digital texts and provides a valuable resource for visual and digital text selection in‐ and outside the classroom.
Reading Math Textbooks: An Algebra Teacher's Patterns of Thinking
Authors: Massey Dixie , Riley Lance
Published: March 2013

FREE author podcast
Paths to accuracy for radiation parameterizations in atmospheric models
Authors: Pincus Robert , Stevens Bjorn
Published: March 2013

Radiative transfer is sufficiently well understood that its parameterization in atmospheric models is primarily an effort to balance computational cost and accuracy. The most common approach is to compute radiative transfer with the highest practical spectral accuracy but infrequently in time and/or space, though errors introduced by this approximation are difficult to quantify. An alternative is to perform spectrally sparse calculations frequently in time using randomly chosen spectral quadrature points. Here we show that purely random quadrature points, though effective in some large‐eddy simulations, are not a good choice for models in which the land surface responds to radiative fluxes because surface temperature perturbations can be large enough, and persistent long enough, to affect model evolution. These errors may be mitigated by choosing teams of spectral points designed to limit the maximum surface flux error; teams, rather than individual quadrature points, are then chosen randomly. The approach is implemented in the ECHAM6 global model and the results are examined using “perfect‐model” experiments on time scales ranging from a day to a month. In this application the approach introduces errors commensurate with the infrequent calculation of broadband calculations for the same computational cost. But because teams need not increase with size, and indeed may become better and more balanced with increased spectral density, improvements in radiative transfer may not need to be traded off against spatiotemporal sampling.
Sustained release of simvastatin from premixed injectable calcium phosphate cement
Authors: Montazerolghaem Maryam , Engqvist Håkan , Karlsson Ott Marjam
Published: March 2013

Locally applied simvastatin is known to promote bone regeneration; however, the lack of suitable delivery systems has restricted its clinical use. In this study we demonstrate for the first time the use of premixed acidic calcium phosphate cement (CPC) as a delivery system for water‐solubilized simvastatin. Freeze‐dried simvastatin β‐hydroxy acid (SVA) was added to the premixed cement paste in four different doses (1, 0.5, 0.25, and 0 mg SVA/g cement). The addition of the drug did not alter the cement setting time (38 min), compression strength (5.54 MPa), or diametral tensile strength (2.62 MPa). In a release study conducted in phosphate buffered saline at 37°C, a diffusion‐controlled release was observed for over a week. Furthermore, the osteogenic effect of the released SVA was demonstrated in vitro. Cell proliferation, alkaline phosphatase activity, and mineralization were assayed after incubation with cement extracts. The lower doses of SVA (0.5 and 0.25 mg SVA/g cement) showed an approximately fourfold increase in mineralization as compared to the control. In conclusion, our findings suggest that premixed acidic CPC is a good option for local delivery of SVA, due to its ability of slowly releasing the drug, leading to a prolonged stimulation of osteogenesis. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 102A: 340–347, 2014.
Promotion of spinal cord axon regeneration by 3D nanofibrous core–sheath scaffolds
Authors: Zamani F. , Amani‐Tehran M. , Latifi M. , Shokrgozar M. A. , Zaminy A.
Published: March 2013

Since spinal cord injury is a complicated problem, neural tissue repair, and regeneration strategies have received a great deal of attention. In this study, a three−dimensional (3D) nanofibrous core–sheath scaffold with nanorough sheath and aligned core were fabricated by a combined electrospinning method with water vortex and two−nozzle system. In vitro and in vivo biological tests were carried out on the poly(lactic−co−glycolic acid) (PLGA) scaffolds. The cell morphology and proliferation evaluation of nerve cells on 3D PLGA scaffolds were studied. Cells were properly orientated along the aligned fiber direction of the scaffold. In animal studies, adult rats received a complete lateral hemisection at the T9–T10 level. Scaffolds were engrafted to bridge 3 mm defects of 10 adult rat spinal cords; 10 rats were used as controls. For 8 weeks, motor and sensory recovery by open field locomotor scale, narrow beam and tail flick tests were assessed. Locomotor and sensory scores of grafted animals were significantly better than the control group. Histological findings demonstrated that the scaffold supports the axonal regeneration of injured spinal cords and regenerating axons were seen to enter the graft and extend along its length. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 102A: 506–513, 2014.
Hydroxyapatite‐coated magnesium implants with improved in vitro and in vivo biocorrosion, biocompatibility, and bone response
Authors: Kim Sae‐Mi , Jo Ji‐Hoon , Lee Sung‐Mi , Kang Min‐Ho , Kim Hyoun‐Ee , Estrin Yuri , Lee Jong‐Ho , Lee Jung‐Woo , Koh Young‐Hag
Published: March 2013

Magnesium and its alloys are candidate materials for biodegradable implants; however, excessively rapid corrosion behavior restricts their practical uses in biological systems. For such applications, surface modification is essential, and the use of anticorrosion coatings is considered as a promising avenue. In this study, we coated Mg with hydroxyapatite (HA) in an aqueous solution containing calcium and phosphate sources to improve its in vitro and in vivo biocorrosion resistance, biocompatibility and bone response. A layer of needle‐shaped HA crystals was created uniformly on the Mg substrate even when the Mg sample had a complex shape of a screw. In addition, a dense HA‐stratum between this layer and the Mg substrate was formed. This HA‐coating layer remarkably reduced the corrosion rate of the Mg tested in a simulated body fluid. Moreover, the biological response, including cell attachment, proliferation and differentiation, of the HA‐coated samples was enhanced considerably compared to samples without a coating layer. The preliminary in vivo experiments also showed that the biocorrosion of the Mg implant was significantly retarded by HA coating, which resulted in good mechanical stability. In addition, in the case of the HA‐coated implants, biodegradation was mitigated, particularly over the first 6 weeks of implantation. This considerably promoted bone growth at the interface between the implant and bone. These results confirmed that HA‐coated Mg is a promising material for biomedical implant applications. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 102A: 429–441, 2014.
Dexamethasone released from cochlear implant coatings combined with a protein repellent hydrogel layer inhibits fibroblast proliferation
Authors: Wrzeszcz Antonina , Dittrich Barbara , Haamann Daniel , Aliuos Pooyan , Klee Doris , Nolte Ingo , Lenarz Thomas , Reuter Günter
Published: March 2013

The insertion of cochlear implants into the inner ear often causes inflammation and fibrosis inside the scala tympani and thus growth of fibrous tissue on the implant surface. This deposition leads to the loss of function in both electrical and laser‐based implants. The design of this study was to realize fibroblast growth inhibition by dexamethasone (Dex) released from the base material of the implant [polydimethylsiloxane (PDMS)]. To prevent cell and protein adhesion, the PDMS was coated with a hydrogel layer [star‐shaped polyethylene glycol prepolymer (sPEG)]. Drug release rates were studied over 3 months, and surface characterization was performed. It was observed that the hydrogel slightly smoothened the surface roughened by the Dex crystals. The hydrogel coating reduced and prolonged the release of the drug over several months. Unmodified, sPEG‐coated, Dex‐loaded, and Dex/sPEG‐equipped PDMS filaments were cocultivated in vitro with fluorescent fibroblasts, analyzed by fluorescent microscopy, and quantified by cell counting. Compared to the unmodified PDMS, cell growth on all modified filaments was averagely 95% ±standard deviation (SD) less, while cell growth on the bottom of the culture dishes containing Dex‐loaded filaments was reduced by 70% ±SD. Both, Dex and sPEG prevented direct cell growth on the filament surfaces, while drug delivery was maintained for the duration of several months. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 102A: 442–454, 2014.
Infrared spectroscopic characterization of carbonated apatite: A combined experimental and computational study
Authors: Ren Fuzeng , Ding Yonghui , Leng Yang
Published: March 2013

A combined experimental and computational approach was employed to investigate the feasibility and effectiveness of characterizing carbonated apatite (CAp) by infrared (IR) spectroscopy. First, an experimental comparative study was conducted to identify characteristic IR vibrational bands of carbonate substitution in the apatite lattice. The IR spectra of pure hydroxyapatite (HA), carbonate adsorbed on the HA surface, a physical mixture of HA and sodium carbonate monohydrate, a physical mixture of HA and calcite, synthetic CAps prepared using three methods (precipitation method, hydrothermal route, and solid‐gas reaction at high temperature) and biological apatites (human enamel, human cortical bone, and two animal bones) were compared. Then, the IR vibrational bands of carbonate in CAp were calculated with density functional theory. The experimental study identified characteristic IR bands of carbonate that cannot be generated from surface adsorption or physical mixtures and the results show that the bands at ∼880, 1413, and 1450 cm−1 should not be used as characteristic bands of CAp since they could result from carbonate adsorbed on the apatite crystals surface or present as a separate phase. The combined experimental and computational study reveals that the carbonate v3 bands at ∼1546 and 1465 cm−1 are, respectively, the IR signature bands for type A CAp and type B CAp. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 102A: 496–505, 2014.
Clinical Decision Making in the Treatment of Complex PTSD and Substance Misuse
Authors: Litt Lisa
Published: March 2013

Treating clients with complex posttraumatic stress disorder (PTSD) who also misuse substances presents a number of clinical challenges. The nature of complex PTSD is that we are faced with the far‐reaching consequences of early and prolonged trauma on clients’ lives, typically interfering with a host of emotional, relational, and functional capacities. Often substance misuse has become an offshoot of this experience, initially an “adaptive” response to unbearable circumstances, but over time exacerbating client dysfunction, at times leading to revictimization, and frequently culminating in a substance use disorder. Many clinicians feel overwhelmed in the face of this myriad of problems. This article provides an overview of some of the clinical choice points facing clinicians in this work: Where do we start? How do we proceed? What do we treat first? How do we handle a dysregulated client? The article attempts to provide some guidance about how to approach these multifaceted decisions, with an emphasis on attending to comorbidity, to assist clinicians in providing symptom‐focused treatment for this complex population.
Decadal‐scale sensitivity of Northeast Greenland ice flow to errors in surface mass balance using ISSM
Authors: Schlegel N-J. , Larour E. , Seroussi H. , Morlighem M. , Box J. E.
Published: March 2013

The behavior of the Greenland Ice Sheet, which is considered a major contributor to sea level changes, is best understood on century and longer time scales. However, on decadal time scales, its response is less predictable due to the difficulty of modeling surface climate, as well as incomplete understanding of the dynamic processes responsible for ice flow. Therefore, it is imperative to understand how modeling advancements, such as increased spatial resolution or more comprehensive ice flow equations, might improve projections of ice sheet response to climatic trends. Here we examine how a finely resolved climate forcing influences a high‐resolution ice stream model that considers longitudinal stresses. We simulate ice flow using a two‐dimensional Shelfy‐Stream Approximation implemented within the Ice Sheet System Model (ISSM) and use uncertainty quantification tools embedded within the model to calculate the sensitivity of ice flow within the Northeast Greenland Ice Stream to errors in surface mass balance (SMB) forcing. Our results suggest that the model tends to smooth ice velocities even when forced with extreme errors in SMB. Indeed, errors propagate linearly through the model, resulting in discharge uncertainty of 16% or 1.9 Gt/yr. We find that mass flux is most sensitive to local errors but is also affected by errors hundreds of kilometers away; thus, an accurate SMB map of the entire basin is critical for realistic simulation. Furthermore, sensitivity analyses indicate that SMB forcing needs to be provided at a resolution of at least 40 km.
Water use efficiency of perennial and annual bioenergy crops in central Illinois
Authors: Zeri Marcelo , Hussain Mir Zaman , Anderson‐Teixeira Kristina J. , DeLucia Evan , Bernacchi Carl J.
Published: March 2013

Sustainable bioenergy production depends upon the efficiency with which crops use available water to produce biomass and store carbon belowground. Therefore, water use efficiency (WUE; productivity vs. annual evapotranspiration, ET) is a key metric of bioenergy crop performance. We evaluate WUE of three potential perennial grass bioenergy crops, Miscanthus × giganteus (miscanthus), Panicum virgatum (switchgrass), and an assemblage of prairie species (28 species), and Zea mays–Glycine max rotation, during the establishment phase in Illinois. Ecosystem WUE (EWUE; net ecosystem productivity vs. ET) was highest in miscanthus, reaching a maximum value of 12.8 ± 0.3 kg ha–1 mm–1 in the third year, followed by switchgrass (7.5 ± 0.3 kg ha–1 mm–1) and prairie (3.9 ± 0.3 kg ha–1 mm–1); the row crop was the lowest. Besides EWUE, harvest‐WUE (HWUE, harvested biomass vs. ET) and net biome productivity‐WUE (BWUE, calculated as net ecosystem production – harvest vs. ET) were also estimated for all crops and years. After three years of establishment, HWUE and BWUE were highest in miscanthus (9.0 ± 2 and 3.8 ± 2.9 kg ha–1 mm–1, respectively) providing a net benefit to the carbon balance, while the row crops had a negative carbon balance and a negative BWUE. BWUE for maize/soybean indicate that this ecosystem would deplete the soil carbon stocks while using the water resources. Switchgrass had the second highest BWUE, while prairie was almost neutral indicating that long‐term carbon sequestration for this agro‐ecosystem would be sensitive to harvest timing with an early harvest removing more biomass, and thus carbon, from the field.
Investigating soil physical properties and yield response in a grassland field using a dual‐sensor penetrometer and EM38
Authors: Sun Yurui , Cheng Qiang , Lin Jianhui , Schellberg Jürgen , Schulze Lammers Peter
Published: March 2013

Precision‐farming applications are mainly based on site‐specific information of soil properties at the field scale. For this purpose, a number of novel sensor techniques have been developed but not intensively tested under different field conditions. This study presents a combined application of a self‐developed dual‐sensor vertical penetrometer (DVP) for measuring volumetric soil water content (VSWC) and cone index (CI), and an EM38 for soil apparent electrical conductivity (ECa) in a pasture (1.4 ha). To verify the feasibility of the DVP for interpreting the depth‐specific information in the field, not only the soil physical properties and their geographical coordinates were measured, but also geo‐referenced yield data were collected. We found that the yield pattern was quite similar to the soil water‐content pattern of each layer (layer‐1: 5–15 cm; layer‐2: 15–25 cm, layer‐3: 25–35 cm) and ECa pattern. Using the map‐based comparisons in conjunction with the statistical analyses, the effect of each measured soil physical property (VSWC, CI, and ECa) on the yield was investigated. The regression between the yield and VSWC at each layer fitted a quadratic equation (R2 = 0.515 at 5–15 cm; R2 = 0.623, at 15–25 cm; R2 = 0.406 at 25–35 cm). The negative correlation between yield and CI at each layer fitted a linear model with R2 ≥ 0.510.
The effect of nitrogen fertilization and no‐till duration on soil nitrogen supply power and post–spring thaw greenhouse‐gas emissions
Authors: Hangs Ryan D. , Schoenau Jeff J. , Lafond Guy P.
Published: March 2013

With a world population now > 7 billion, it is imperative to conserve the arable land base, which is increasingly being leveraged by global demands for producing food, feed, fiber, fuel, and facilities (i.e., infra‐structure needs). The objective of this study was to determine the effect of varying fertilizer‐N rates on soil N availability, mineralization, and CO2and N2O emissions of soils collected at adjacent locations with contrasting management histories: native prairie, short‐term (10 y), and long‐term (32 y) no‐till continuous‐cropping systems receiving five fertilizer‐N rates (0, 30, 60, 90, and 120 kg N ha–1) for the previous 9 y on the same plots. Intact soil cores were collected from each site after snowmelt, maintained at field capacity, and incubated at 20°C for 6 weeks. Weekly assessments of soil nutrient availability along with CO2and N2O emissions were completed. There was no difference in cumulative soil N supply between the unfertilized long‐term no‐till and native prairie soils, while annual fertilizer‐N additions of 120 kg N ha–1were required to restore the N‐supplying power of the short‐term no‐till soil to that of the undisturbed native prairie soil. The estimated cumulative CO2‐C and N2O‐N emissions among soils ranged from 231.8–474.7 g m–2to 183.9–862.5 mg m–2, respectively. Highest CO2fluxes from the native prairie soil are consistent with its high organic matter content, elevated microbial activity, and contributions from root respiration. Repeated applications of ≥ 60 kg N ha–1resulted in greater residual inorganic‐N levels in the long‐term no‐till soil, which supported larger N2O fluxes compared to the unfertilized control. The native prairie soil N2O emissions were equal to those from both short‐ and long‐term no‐till soils receiving repeated fertilizer‐N applications at typical agronomic rates (e.g., 90 kg N ha–1). Eighty‐eight percent of the native soil N2O flux was emitted during the first 2 weeks and is probably characteristic of rapid denitrification rates during the dormant vegetative period after snowmelt within temperate native grasslands. There was a strong correlation (R20.64;p< 0.03) between measured soil Fe‐supply rate and N2O flux, presumably due to anoxic microsites within soil aggregates resulting from increased microbial activity. The use of modern no‐till continuous diversified cropping systems, along with application of fertilizer N, enhances the soil N‐supplying power over the long‐term through the build‐up of mineralizable N and appears to be an effective management strategy for improving degraded soils, thus enhancing the productive capacity of agricultural ecosystems. However, accounting for N2O emissions concomitant with repeated fertilizer‐N applications is imperative for properly assessing the net global warming potential of any land‐management system.
Interpretation of lysimeter weighing data affected by wind
Authors: Nolz Reinhard , Kammerer Gerhard , Cepuder Peter
Published: March 2013

Weighing lysimeters are valuable devices for measuring water‐balance components with high temporal resolution and high accuracy. However, some older lysimeter facilities still operate with lever‐arm‐counterbalance weighing systems that are sensitive to disturbances, e.g., forces exerted by wind. Filtering and averaging are commonly used for processing noisy raw data. We studied some data of a lever‐arm weighing system and performed additional experiments in order to (1) determine the measurement accuracy of the current weighing scheme (facility, and measuring and averaging procedure) regarding wind effects, (2) describe the oscillation behavior, (3) test the mechanical performance of the system, and (4) adapt the averaging procedure with respect to improved interpretation of the weighing data.

The measurement accuracy for a wind velocity < 5 m s–1, measured in 10 m height, was ≈ ± 0.4 kg (equivalent to ± 0.14 mm); at a higher wind velocity, the accuracy was three times lower, but there was no linear relationship. Additional experiments showed that the weighing system is oscillating with more or less irregular amplitudes. A loading–unloading experiment delivered proper results of the measured loads. The mechanical system reacted immediately, and no directional effects were found. However, small changes of < 1 kg could hardly be determined due to the oscillations. A time series of raw data measured every 2 s served as basis for improving the averaging method. A moving average from 64 values was computed representing the currently used method, and serving as reference. With this procedure an accuracy of ± 0.38 kg could be reached. Averaging 150 values led to an accuracy of ± 0.28 kg (0.1 mm) for a wind velocity < 5 m s–1.
Long‐term tillage effects on the distribution of phosphorus fractions of loess soils in Germany
Authors: Piegholdt Christiane , Geisseler Daniel , Koch Heinz‐Josef , Ludwig Bernard
Published: March 2013

Different tillage systems may affect P dynamics in soils due to differently distributed plant residues, different aggregate dynamics and erosion losses, but quantitative data are scarce. Objectives were to investigate the effect of tillage on the availability of P in a long‐term field trial on loess soils (Phaeozems and Luvisols) initiated from 1990 to 1997. Four research sites in E and S Germany were established with a crop rotation consisting of two times winter wheat followed by sugar beet. The treatments were no‐till (NT) without cultivation, except for seedbed preparation to a depth of 5 cm before sugar beet was sown and conventional tillage (CT) with mouldboard plowing down to 25–30 cm. Soil P was divided into different pools by a sequential extraction method, and total P (Pt) in the single P fractions was extracted by digesting the extracts of the fractionation to calculate the contents of organic P. The Pt content (792 mg [kg soil]–1) in the topsoil (0–5 cm) of NT was 15% higher compared to CT, while with increasing depth the Pt content decreased more under NT than under CT. This was also true for the other P fractions except for residual P. The higher P contents in the topsoil of NT presumably resulted from the shallower incorporation of harvest residues and fertilizer P compared to CT, whereas estimated soil losses and thus also P losses due to water erosion were only small for both treatments. Contents of oxalate‐extractable Fe and organic C were positively related to the labile fractions of inorganic P, while there was a high correlation of the stable fractions with the clay contents and pH. Multiple regression analyses explained 50% of the variability of these P fractions. Overall, only small differences in the P fractions and availability were observed between the long‐term tillage treatments.
A pilot staging system to predict persistent obstructive sleep apnea in children following adenotonsillectomy
Authors: Smith David F. , Benke James R. , Yaster Susan , Boss Emily F. , Ishman Stacey L.
Published: March 2013

Objectives/Hypothesis

A recent meta‐analysis by Friedman et al. found that 66% of children have resolution of obstructive sleep apnea (OSA) after tonsillectomy and adenoidectomy (TA). However, accurate predictors of persistent OSA in children despite surgery are difficult to identify. We evaluate the utility of staging children with OSA using characteristics predictive of adult palatoplasty success.

Study Design

A retrospective analysis of children who underwent sleep studies before and after TA in a tertiary care center from 2008 through 2011.

Methods

Tonsil size (TS)/modified Mallampati position score (MMP)/body mass index (BMI) z Score were used to categorize patients into a three‐ and four‐stage tonsillectomy staging system. Stage 1 included patients with low MMP scores/large tonsils; stage 2 with low MMP scores/small tonsils or high MMP scores/large tonsils. Stage 3 included patients with high MMP scores/small tonsils. For the four‐stage system, any patient with a BMI z Score ≥2.0 was stage 4.

Results

Thirty‐five patients (14 females) were included (mean age, 6.8 years; range, 1.0–18.6 years). OSA severity ranged from mild (n = 6), moderate (n = 10), to severe (n = 19), with a mean respiratory disturbance index (RDI) of 20.9 before surgery and 2.4 after. Similar to results seen for adult palatoplasty, staging by TS/MMP/BMI corresponded with response to surgery. In stage 1 to 2, 11/17 (64.7%) children had RDI <1.5 postoperatively, with decreasing TA success rates in stages 3 to 4 at 10/18 (55.5%). Although these results were not statistically significant (P = .14), the trend was similar to the adult analysis.

Conclusions

A trend toward a dose‐response relationship was seen between physical exam staging and persistent OSA after TA. Further data collection and analysis with a larger sample size are warranted.

Level of Evidence

4. Laryngoscope, 2013
Outcome of endoscopic resection tracheoplasty for treating lambdoid tracheal stomal stenosis
Authors: Nouraei S. A. Reza , Sandhu Guri S.
Published: March 2013

Objectives/Hypothesis

To evaluate the efficacy of endoscopic resection tracheoplasty (ERT) for treating post‐tracheotomy stomal stenosis caused by inward collapse of tracheal ring remnants.

Study design

Prospective observational study.

Methods

Between 2007 and 2012, we treated 40 patients with “lambdoid” tracheal deformity with a two‐staged minimally invasive procedure undertaken using suspension microtracheoscopy and high‐frequency jet ventilation. The first procedure entailed CO2 laser photoablation of collapsed tracheal rings and dilatation. The second procedure, performed 6 to 8 weeks later, involved ablation of residual structural obstruction, removal of granulation tissue, and intralesional corticosteroid injection. Perioperative patient and lesion characteristics and results of treatment were assessed.

Results

There were 22 males and 18 females, and mean age at first treatment was 59 years. There were 17 cases of scarring at the postero‐lateral tracheal groove (trachealis blunting), and 22 patients had age‐adjusted Charlson comorbidity scores greater than 4. All patients without trachealis blunting were successfully managed endoscopically, with only one patient requiring one additional endoscopic treatment. Seven patients with trachealis blunting needed additional treatment, and four patients had tracheal resection (P = 0.013). All patients were decannulated, and 75% of patients achieved good dyspnea outcomes. Patients with low morbidities were significantly more likely to achieve good dyspnea outcomes (P < 0.027). There were no treatment‐related worsenings of voice or swallowing.

Conclusions

ERT is an effective minimally invasive treatment for intubation‐related lambdoid tracheal stenosis. It achieves a successful outcome while avoiding the risks associated with open surgery. We recommend its more widespread use for treating patients with this condition.

Level of Evidence

4. Laryngoscope, 2012
Scattering for strictly hyperbolic systems with time‐dependent coefficients
Authors: Matsuyama Tokio , Ruzhansky Michael
Published: March 2013

The present paper is devoted to finding conditions on the occurrence of scattering for strictly hyperbolic systems with time‐dependent coefficients whose time‐derivatives are in L1 in time. More precisely, it will be shown that the solutions are asymptotically free if the coefficients are stable in the sense that their improper Riemann integrals converge as t → ±∞, while each nontrivial solution with radially symmetric data is never asymptotically free provided that the coefficients are not stable as t → ±∞. As a by‐product, wave and scattering operators can be constructed. An important feature is that assumptions on only one derivative of the coefficients are made so that the results would be applicable to the asymptotic behaviour of Kirchhoff systems.
Clinical and mutation analysis of 51 probands with anophthalmia and/or severe microphthalmia from a single center
Authors: Gerth‐Kahlert Christina , Williamson Kathleen , Ansari Morad , Rainger Jacqueline K. , Hingst Volker , Zimmermann Theodor , Tech Stefani , Guthoff Rudolf F. , van Heyningen Veronica , FitzPatrick David R.
Published: March 2013

Clinical evaluation and mutation analysis was performed in 51 consecutive probands with severe eye malformations – anophthalmia and/or severe microphthalmia – seen in a single specialist ophthalmology center. The mutation analysis consisted of bidirectional sequencing of the coding regions of SOX2, OTX2, PAX6 (paired domain), STRA6, BMP4, SMOC1, FOXE3, and RAX, and genome‐wide array‐based copy number assessment. Fifteen (29.4%) of the 51 probands had likely causative mutations affecting SOX2 (9/51), OTX2 (5/51), and STRA6 (1/51). Of the cases with bilateral anophthalmia, 9/12 (75%) were found to be mutation positive. Three of these mutations were large genomic deletions encompassing SOX2 (one case) or OTX2 (two cases). Familial inheritance of three intragenic, plausibly pathogenic, and heterozygous mutations was observed. An unaffected carrier parent of an affected child with an identified OTX2 mutation confirmed the previously reported nonpenetrance for this disorder. Two families with SOX2 mutations demonstrated a parent and child both with significant but highly variable eye malformations. Heterozygous loss‐of‐function mutations in SOX2 and OTX2 are the most common genetic pathology associated with severe eye malformations and bi‐allelic loss‐of‐function in STRA6 is confirmed as an emerging cause of nonsyndromal eye malformations.
New properties of guided electromagnetic wave propagation in chiral media
Authors: Gómez Álvaro , Solano Miguel A. , Fernández Óscar , Vegas Ángel
Published: March 2013

In this paper, we present a new study of the electromagnetic wave propagation inside a rectangular waveguide partially loaded with an isotropic chiral medium, by means of the coupled mode method. Along this analysis some new features related to the variation of the propagation constant versus frequency and the chirality parameter, which have not been previously reported in the literature, are introduced. Among them, we highlight the existence of a frequency point wherein all the dispersion curves cross each other, and the increasing of the cutoff frequency of the fundamental mode with the chirality of the medium. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:1206–1212, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27534
Microstrip bandpass filters with series‐LC resonator loaded coupled lines
Authors: Chao Shih‐Fong
Published: March 2013

In this article, series‐LC resonator loaded coupled lines are proposed to implement microstrip bandpass filters. The proposed loaded coupled line can generate three tunable transmission zeros. Conditions for the transmission zeros of the series‐LC resonator loaded coupled lines are analyzed and discussed. To demonstrate the applications, two second‐order bandpass filters using the proposed loaded coupled‐lines are designed with wide stopband rejections. The measured results show a good agreement with the simulations. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:1273–1276, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27542
A novel miniaturized UWB antenna with four band‐notches
Authors: Xu Jie , Shen Dongya , Zheng Jianfeng , Zhang Xiupu , Wu Ke
Published: March 2013

In this article, an effective design method is presented to design a miniaturized UWB antenna with four band‐notches. By carefully integrating C‐shaped slots, L‐shaped open circuit stub, and T‐shaped parasitic strip onto the primitive miniaturized antenna, four band‐notches (VSWR > 2) could be achieved at 3.38–3.65 GHz, 4.95–6.05 GHz, 7.42–7.78 GHz, and 8.1–8.9 GHz to reject WiMAX, WLAN, X‐band satellite communication, and ITU 8 GHz band signals. Simulated and measured results show that this antenna could operate from 3.15–11.1 GHz (VSWR < 2), and maintain omnidirectional directivity patterns at H‐plane. Moreover, the proposed antenna has a very compact size of 18.6 × 22 × 1.5 mm3. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:1202–1206, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27546
Wideband rectangular wearable jeans antenna
Authors: Roy Bivas , Sarkar Partha Pratim , Chowdhury Santosh
Published: March 2013

In this article, the design, fabrication, and measurement of a wideband wearable textile (jeans) patch antenna is presented.The substrate of the designed antenna was made by jeans cotton textile material, whereas the radiating element and ground plate was made by thin film copper foil. The copper foil was pasted by using synthetic resin adhesive on the textile (jeans) material. We have measured the dielectric constant of the jeans material (textile substrate) by using ring resonator method (Rida et al., IEEE Antennas Propag Mag 51 (2009) 13–23; Yang et al., IEEE Trans Microwave Theory Tech (2007) 2894–2901]. The effect of thickness of the jeans substrate for designing and fabrication of wideband antenna was also investigated in this article. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:1270–1273, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27548
Compact microstrip dual‐passband filters based on stepped‐impedance resonators
Authors: Tsai Lin‐Chuan
Published: March 2013

In this article, a new coupling configuration of the stepped‐impedance resonator is proposed to implement dual‐passband filters with the small circuit size.We design the filter with higher selectivity based on SIR directing‐coupling, cross‐coupling, input and output external quality factors. Through resonance characteristics of a SIR, the second‐resonant frequency can be tuned by adjusting structure parameters. The agreement between measured results and full‐wave simulation prediction validates the feasible configuration of the proposed filters. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:1230–1233, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27551
An annular‐ring slot antenna for CP operation
Authors: Kumar Ajay , Gautam A. K. , Kanaujia Binod Kr.
Published: March 2013

An annular‐ring slot antenna with pair of slits and truncated corner for CP operation is proposed. A pair of slits and truncated corners are used to enhance axial ratio bandwidth. The proposed antenna is fabricated and simulated to analyze its radiation characteristics. Simulated results show a good agreement with experimental results. The antenna also shows much larger CP bandwidths than earlier reported results. The measured impedance bandwidth and 3‐dB axial ratio bandwidth (ARBW) of the proposed antenna are 94.2 and 73.8%, respectively. The proposed antenna shows consistent return loss and radian pattern for entire frequency band. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:1418–1422, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27563
Wideband operations for compact single‐fed circularly polarized microstrip antenna
Authors: Wu Jianjun , Yang Xi , Yin Yingzeng , Xu Feng
Published: March 2013

A compact single‐fed circularly polarized microstrip antenna is proposed for radio frequency identification readers.The antenna consists of a square patch with truncated corners printed a thick FR4 substrate and a probe‐fed metal strip that is adopted for wideband operations. Results show that the antenna achieves a 10‐dB return loss bandwidth of 11.02% (2.31–2.59 GHz) and a 3‐dB axial ratio (AR) bandwidth of 2.45% (2.42–2.48 GHz) or 6‐dB AR bandwidth of 4.9% (2.39–2.51 GHz). © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:1254–1257, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27568
Analysis of stripline configurations loaded with complementary split ring resonators
Authors: Falcone Francisco , Illescas Jesús , Jarauta Eduardo , Estevez Aritz , Marcotegui Jose Antonio
Published: March 2013

In this article, a stripline planar transmission line loaded with complementary split ring resonators (CSRRs), in order to obtain a frequency selective behavior. Due to the quasi‐static resonance frequency of the CSRR elements, given by the excitation by normal incident E‐field, a rejected frequency band can be observed. Simulation as well as measurement results reveal the possibility to apply this type of configuration for the implementation of devices in stripline technology. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:1250–1254, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27569
100 Gb/s long‐reach WDM‐PON implemented by using directly modulated RSOA
Authors: Tawade Laxman
Published: March 2013

This article presents long reach wavelength division multiplexing passive optical network (WDM‐PON) system capable of delivering 100 Gb/s data to each subscriber. For cost‐effectiveness, WDM‐PON is implemented in loopback configuration using directly modulated reflective semiconductor optical amplifiers (RSOAs) at 25 Gb/s. We use four RSOAs at each optical network unit for the 100‐Gb/s upstream transmission. The operating wavelengths of these RSOAs are separated by the free‐spectral range of the cyclic arrayed waveguide gratings used at the central office and remote node (RN) for (de)multiplexing the WDM channels. We extend the maximum reach of this WDM‐PON to 123 km by using Erbium‐doped fiber amplifiers at the RN. The results show that the error‐free transmission can be achieved for all WDM channels in the wavelength range of >35 nm with sufficient power margins. Bit error rate and Q‐factor were measured to demonstrate the proposed scheme. In this article, long reach and large data service aspects of an access network are presented. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:1426–1430, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27581 DOI 10.1002/mop.27572
A low profile, wideband cavity‐backed bowtie antenna
Authors: Zhou Shi‐Gang , Huang Guan‐Long , Chio Tan‐Huat
Published: March 2013

In this article, a cavity‐backed bowtie antenna (CBBA) is proposed and investigated.Compared with the conventional CBBA, parasitic stubs are added to the open‐end of the Bowtie. The parasitic stubs provide capacitive loading and allows the design to exhibit a low profile over a relatively wide bandwidth. Parametric studies are performed to optimize the antenna performance. For verification, a prototype was fabricated and measured. Experimental results show the VSWR of less than 2.0:1 from 1.97 to 8.5 GHz. However, the radiation pattern degrades beyond 7.5 GHz. This limits the operating bandwidth to about 117%. The height of the prototype is 15 mm which is only 0.1 λmax (λmax is the wavelength at the lowest operating frequency) © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:1422–1426, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27573
Visible light based high accuracy indoor localization using the extinction ratio distributions of light signals
Authors: Yang Se‐Hoon , Kim Deok‐Rae , Kim Hyun‐Seung , Son Yong‐Hwan , Han Sang‐Kook
Published: March 2013

In this article, we propose an indoor location estimation algorithm that uses the signal extinction ratio distribution of LED‐based visible light communication.To improve the positioning accuracy, we use the received extinction ratio from different LED transmitters. In order to mitigate interference between transmitters, a location code was sent using time division multiplexing (TDM). We verified the feasibility of the proposed position estimation algorithm with an experimental demonstration. The proposed algorithm provided positioning accuracy with a 1.5787‐cm mean distance error for a given equilateral triangle cell with three 60‐cm sides. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:1385–1389, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27575
A CMOS quadrature voltage‐controlled oscillators using common‐drain coupling transistors
Authors: Jang Sheng‐Lyang , Liu You‐Wei , Chang Chia‐Wei , Juang Miin‐Horng
Published: March 2013

This article presents a fully integrated quadrature cross‐coupled voltage controlled oscillator (QVCO) using common‐drain transistor instead of common‐source transistor as a coupling device.The prototype 3.8 GHz QVCO in 0.18 μm CMOS process is proposed to generate four output phases and it uses two p‐core cross‐coupled VCOs and nMOS coupling devices. The proposed QVCO oscillates from 3.6 to 3.84 GHz and the power consumption is 7.24 mW at 0.74 V supply voltage. The measured phase noise is –126.19 dBc/Hz at 1 MHz offset frequency from the carrier frequency 3.745 GHz. The VCO occupies a chip area of 1.08 ×0.924 mm2 and provides a figure of merit of –189.05 dBc/Hz. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:1262–1266, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27578
A novel design of triple‐band monopole antenna for multi‐input multi‐output communication
Authors: Ojaroudi Nasser , Ojaroudi Mohammad
Published: March 2013

In this article, a novel wireless local area network (WLAN) frequency range monopole antenna is designed and manufactured for multi‐input multi‐output (MIMO) applications. The proposed antenna consists of two L‐shaped slots in the S‐shaped radiating patch. In this structure, the S‐shaped monopole antenna can create dual resonances within the WLAN range. Placement of two L‐shaped slots within the S‐shaped monopole antenna creates an extra resonance; the desired resonant frequencies are obtained by adjusting the dimension of the S‐shaped and the L‐shaped structures. The operating frequencies of the proposed antenna are 2.4/5.2/5.8 GHz, which covers WLAN system. Various configurations of array of this S‐shaped monopole antenna for MIMO application are also studied. Prototypes of the proposed antenna have been constructed and studied experimentally. Good return loss and radiation pattern characteristics are obtained in the frequency band of interest. Simulated and measured results are presented to validate the usefulness of this small proposed antenna structure for MIMO applications. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:1258–1262, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27579
Highly linear microstrip wideband bandpass filter with switchable notched band for wireless applications
Authors: Rabbi K. , Athukorala L. , Panagamuwa C. , Vardaxoglou J. C. , Budimir D.
Published: March 2013

This article presents a highly linear reconfigurable bandpass filter embedded with a switchable notch structure to get a band‐notched characteristic at a specified frequency.A single PIN diode (BAP65‐02) is used for the purpose of switching the notch. An optical switch, comprised of a silicon dice activated using near infrared light is also investigated as an alternative to the PIN diode. While the PIN diode or the optical switch is in the ON state this reconfigurable filter behaves as a bandpass filter with a notch at 2.4 GHz in order to reject WLAN interference while a full band response is obtained in the OFF state. The proposed filter is able to achieve good linearity using PIN diode with IIP3 of 47 dBm and there is no significant loss. A prototype is fabricated, and measured results are compared to simulations. A good agreement has been achieved between simulated and measured results. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:1331–1335, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27585
Compact dual‐band bandpass filter using spiral resonators and short‐circuited stub‐loaded resonator
Authors: Song Kaijun , Zhang Fan , Zhuge Chunlin , Fan Yong
Published: March 2013

A compact dual‐band bandpass filter (BPF) using spiral resonators and short‐circuited stub‐loaded dual‐mode resonator is presented.Two different transmission paths and source‐load cross coupling are used to realize independently controllable bandwidths for each passband and good frequency selectivity. The coupling scheme and current distributions are applied to demonstrate the flexible design approach. A dual‐band BPF is designed, simulated, and fabricated to demonstrate the performance of the proposed dual‐band filter. The measured results show that the fabricated dual‐band BPF has two passbands centered at 2.45 and 3.55 GHz with the fractional bandwidths of 5 and 7%. The insertion loss is 1.2 and 1.3 dB at the lower and upper passbands, respectively, and the return loss within the two passbands is greater than 17 dB. The measured results show good agreement with the simulated ones. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:1393–1398, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27589
A circularly polarized olympic‐like logo antenna for 900 MHZ UHF RFID reader
Authors: Sim Chow‐Yen‐Desmond , Chi Chin‐Jen
Published: March 2013

The design of a square‐shaped patch antenna loaded with an Olympic‐like logo slot for 900 MHz UHF RFID reader applications is studied.To achieve good circularly polarized (CP) radiation, an additional narrow perturbation slot is also loaded centrally across the logo. By further applying the L‐shaped probe‐fed method, desirable 3‐dB Axial Ratio (AR) and 10‐dB impedance bandwidth of 3.72% and 30%, respectively, can be achieved. From the experimental results, gain level and efficiency of more than 6 dBic and 89% were also measured, respectively. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:1358–1360, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27591