bluuebunny/crossref_metadata_2025 huggingface dataset:
Current practice in injection augmentation of the vocal folds: Indications, treatment principles, techniques, and complications
Authors: Sulica Lucian , Rosen Clark A. , Postma Gregory N. , Simpson Blake , Amin Milan , Courey Mark , Merati Albert
Published: December 2009

Objectives/Hypothesis:

To identify contemporary indications, treatment principles, technique, injection materials, complications, and success rates of vocal fold injection augmentation.

Study Design:

Multi‐institutional retrospective review.

Methods:

Records of patients undergoing injection augmentation at seven university medical centers from July 2007 through June 2008 were reviewed for information regarding diagnosis, unilateral or bilateral injection, route of injection, anesthesia, treatment site (office or operating room), material used, reason for technique selected, and technical success.

Results:

In 12 months, 460 injections were performed, 236 (51%) in awake, unsedated patients, and 224 (49%) under general anesthesia. Indications included vocal fold paralysis (248; 54%), paresis (97; 21%), atrophy (68; 15%) and scar (47; 10%). Scar was more likely to be treated in the operating room (P = .000052). In awake patients, 112 (47%) injections were performed by transcricothyroid approach, 55 (23%) by peroral approach, 49 (21%) by transthyrohyoid membrane approach, and 20 (8%) by transthyroid cartilage approach. Neither technical success rate (99% vs. 97%) nor complication rate (3% vs. 2%) differed between awake and asleep techniques. The most common materials in the clinic setting were methylcellulose (35%), bovine collagen (28%), and calcium hydroxylapatite (26%); in the operating room these were calcium hydroxylapatite (36%) and methylcellulose (35%). Calcium hydroxylapatite was more likely to be used under general anesthesia (P = .019). Five‐year data show that the use of injection in the awake patient rose from 11% to 43% from 2003 to 2008.

Conclusions:

Injection augmentation remains a safe, effective, and clinically practical treatment with a high rate of success, whether performed in the awake or asleep patient. The rapid adoption of awake injection over the past 5 years speaks to its clinical utility. Complication rates are low and equivalent to those under general anesthesia. Otolaryngologists continue to use a variety of techniques and materials to treat a range of conditions of glottic insufficiency. Laryngoscope, 2010
Calcium hydroxylapatite injection laryngoplasty for the treatment of presbylaryngis: Long‐term results
Authors: Kwon Tack‐Kyun , An Soo‐Youn , Ahn Jae‐Cheul , Kim Kwang Hyun , Sung Myung‐Whun
Published: December 2009

Objectives/Hypothesis:

Presbylaryngis is a normal part of the aging process, but many people visit hospitals with communication difficulties. The authors evaluated the efficacy of calcium hydroxylapatite (CaHA) injection laryngoplasty in patients with presbylaryngis.

Study Design:

Retrospective review.

Methods:

Thirty‐three patients with diagnosed presbylaryngis were administered a CaHA injection, and 17 of these patients without other vocal pathologies were included in the analysis. All 17 were male (mean age 65.9 years), mean follow‐up duration was 335 days, and all injections were performed through the cricothyroid membrane under local anesthesia in a clinic.

Results:

Subjective ratings, perceptual ratings, maximum phonation time, and closed quotients significantly improved after injection, and these improvements persisted without significant change for over 12 months. No major complications were encountered except for transient hematoma, pain, and a foreign body sensation.

Conclusions:

The authors conclude that CaHA injection laryngoplasty offers an effective and safe means of treating presbylaryngis. Laryngoscope, 2010
Value‐driven Internet shopping: The mental accounting theory perspective
Authors: Gupta Sumeet , Kim Hee‐Woong
Published: December 2009

When faced with competition and the ease with which customers can compare prices across sellers, Internet vendors often lower prices in a bid to increase sales. However, recent research reports that even price‐sensitive customers do not always purchase from Internet vendors offering the lowest prices. In contrast, value has been considered a key motivator of customer decision making in economics and marketing. However, little is known about the role and effect of value in Internet shopping. This study examines online customer purchase decision making from the value perspective based on mental accounting theory. This study also identifies monetary (perceived price) and non‐monetary (perceived risk, convenience, and pleasure) determinants of value. This study further explains how the individual determinants affect online purchase decision making directly and indirectly though value perception. The findings of this study offer Internet vendors practical suggestions for increasing online sales. This study, with its results, also helps advance knowledge of electronic commerce. © 2009 Wiley Periodicals, Inc.
Price setting behaviour in the Netherlands: results of a survey
Authors: Hoeberichts Marco , Stokman Ad
Published: December 2009

Using a survey among Dutch firms on price setting behaviour in the Netherlands the study identifies how sticky prices are, which prices are sticky and why they are sticky. The most distinctive feature of the Dutch survey is its broad coverage of the business community (seven sectors and seven size classes), including the service sector and small firms. Our primary finding is that price setting behaviour depends critically on both a firm's size and the competitive environment it faces. Small firms in particular adopt more rigid pricing policies, and the weaker the competition a firm faces, the stickier a company's price will be. Furthermore, we find that wholesale and retail prices are more flexible than those for business‐to‐business services. The survey suggests that explicit and informal contracting are the most important sources of price stickiness. Menu costs and psychological pricing—two prominent explanations of price stickiness in the literature—are of minor importance. Finally, there is clear evidence of asymmetries in shocks driving price increases and decreases. Copyright © 2009 John Wiley & Sons, Ltd.
Multistep mechanism of probiotic bacterium, the effect on innate immune system
Authors: Amit‐Romach Einat , Uni Zehava , Reifen Ram
Published: December 2009

The etiology and pathogenesis of inflammatory bowel disease are still not fully understood. However, evidence from both animal models and clinical observations suggests luminal bacteria as the most probable inducer of this disease. The intestinal bacterial microbiota may be modified by dietary addition of viable probiotic bacteria, thereby constituting an alternative approach to disease prevention and treatment. The aim of this study was to evaluate and compare the effects of two probiotic regiments;Lactobacillus GGand a mixture ofStreptococcus thermophilus,Lactobacillus acidophilus, andBifidobacterium lactis(YO‐MIX™ Y 109 FRO 1000) in both normal and trinitrobenzenesulfonic acid colitis‐induced rats. Colon morphology and damage were evaluated histologically; colonic tissues were used for mRNA analysis, using real‐time PCR. Administration of both probiotics reduced the expression of proinflammatory cytokines tumor necrosis factor‐α and IL‐6 and increased the expression of mucin 2 in compared with colitis group and reduced the inflammatory response. These results provide additional support for the positive effect of probiotics in the gut and may shed light on the mechanism by which probiotic bacteria exert their action in an animal model.
Dietary intake and depressive symptoms: A systematic review of observational studies
Authors: Murakami Kentaro , Sasaki Satoshi
Published: December 2009

The importance of research into the possible role of dietary intake in depressive symptoms is emphasized by the fact that diet is modifiable. We systematically reviewed observational studies investigating the association between dietary intake and depressive symptoms published in English as of December 2008. Using the PubMed database, 34 publications (23 cross‐sectional, 10 prospective cohort, and 1 case‐control studies) were identified. The number of subjects (n=80–27 111), age of subjects (15–97 years), dietary assessment method (dietary record, diet history interview, and validated and non‐validated dietary questionnaire), depressive symptom assessment (discharge diagnosis, established scale, and self‐reported information) varied among studies. Dietary variables most frequently investigated included long chain n‐3 PUFA, fish, folate, and other B vitamins. Most studies found no association between dietary variables and depressive symptoms. However, most studies included at least one important methodological limitation, such as no inference for causality, unreliable or rough assessment of diet or depressive symptoms, inadequate treatment of potential confounding factors, and ignorance of the possible mediating or confounding influence of other dietary variables. Further evidence from well‐designed observational studies is required to confirm or refute the association between dietary intake and depressive symptoms in free‐living settings.
Increased plasma n‐3 polyunsaturated fatty acid is associated with improved insulin sensitivity in type 2 diabetes in China
Authors: Huang Tao , Wahlqvist Mark L. , Xu Tongcheng , Xu Amei , Zhang Aizhen , Li Duo
Published: December 2009

Increased tissue n‐3 polyunsaturated fatty acid (PUFA) is associated with improved insulin sensitivity in type 2 diabetes. However, this relationship among Chinese is not clear. To investigate the relationship between plasma phospholipids (PL) fatty acid composition and insulin resistance (IR) in type 2 diabetes mellitus, 186 type 2 diabetes and 180 healthy subjects were studied in this case‐control study. In the sex, age and BMI controlled partial correlation, homeostasis model assessment (HOMA)‐IR and blood glucose was significantly negatively correlated with plasma PL n‐3 PUFA, 20:5n‐3 and ratio of n‐3:n‐6 (p<0.01), and positively correlated with n‐6 PUFA (p<0.001) and saturated fatty acid (p<0.05) in the diabetes patients. PL 22:6n‐3 was also significantly negatively correlated with HOMA‐IR (p<0.01), but not with blood glucose. Fasting insulin was significantly negatively correlated with plasma PL n‐3 PUFA, 20:5n‐3, 22:6n‐3 and ratio of n‐3:n‐6 (p<0.01). The 18:3n‐3 was not associated with HOMA‐IR and fasting insulin. The results suggested that increased plasma PL n‐3 PUFA, 20:5n‐3, 22:6n‐3 and ratio of n‐3:n‐6 PUFA was associated with decreased HOMA‐IR in type 2 diabetes. Increased plasma PL n‐3 PUFA improves insulin sensitivity in type 2 diabetes.
Two novel extremely low‐profile slot‐coupled two‐element patch antennas for UHF RFID of people
Authors: Švanda Milan , Polívka Milan
Published: December 2009

Novel type of extremely low‐profile low‐dielectric constant substrate antenna, based on two‐element slot‐coupled shorted‐patch structure for UHF RFID applications has been developed. We use two different methods for tuning the complex input impedance—dipole excitation and direct excitation with tuning slots. Both credit card‐sized antennas exhibit the antenna efficiency better than ∼50%, irrespective of whether they are placed in free space or enclosed to either metallic or human body. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 249–252, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24894
LTCC‐based vertical via interconnects for RF MEMS packaging
Authors: Bang Yong‐Seung , Kim Jung‐Mu , Kim Jong‐Man , Kim Yong‐Kweon , Jang Yun‐Ho
Published: December 2009

This article reports on a low temperature cofired ceramic (LTCC)‐based RF MEMS packaging and its electrical modeling using lumped elements and microstrip lines. An LTCC cap with vertical vias was flip‐chip bonded with a glass substrate, where a coplanar waveguide (CPW) formed to measure the RF characteristics of packaging structure. We measured return loss (S11) and insertion loss (S21) of the fabricated packaging structure in a frequency range of 1 to 30 GHz. The parameters of two different equivalent circuits using lumped elements and physical microstrip lines were extracted from the measured results. The mean absolute errors (MAEs) were calculated to show the agreement between measured properties and electrical equivalent circuits. The calculated MAEs were 0.591 dB (S11) and 0.146 dB (S21) for lumped elements, and 0.926 dB (S11) and 0.179 dB (S21) for microstrip lines, respectively. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 252–257, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24895
Medium power C‐band array amplifier featured ultra low residual phase noise
Authors: Shtin Nicolas A. , López Romero José Mauricio
Published: December 2009

This article deals with a design and performance evaluation of a medium power C‐band array amplifier based on SiGe hetero‐junction bipolar transistors (HBT). The proposed power amplifier (PA) contains four identical HBT stages coupled by the means of compact power splitting/summing microstrip networks. The designed PA exhibits a very low phase noise level of −165 dBc/Hz at 1 kHz offset frequency, and it is distinguished by a high output power havingP1dB= +26 dBm and high power added efficiency approaching to 40%. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 292–295, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24896
Theoretical and experimental study on the fiber optic displacement sensor with two receiving fibers
Authors: Harun Sulaiman Wadi , Yang H. Z. , Yasin Moh , Ahmad H.
Published: December 2009

The intensity‐modulation‐based displacement sensor with two receiving fibers is theoretically and experimentally studied. Themathematical model of the proposed sensor is developed and the simulated responses are obtained to be in a good agreement with the experimental results. Compared with the conventional sensor with only one receiving fiber, the proposed sensor has a better linearity range because it has a larger area to receive the reflected light from the target. However, the sensitivity of both sensors is almost similar. Theproposed sensor has the maximum linearity ranges of 2.5 μm and 0.9 μm at the back and front slopes, respectively. The linearity ranges are improved by about 44% compared with the conventional sensor. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 373–375, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24900
A miniature frequency synthesizer module in W‐band
Authors: Ruimin Mingzhou Zhan , Lin Xu Weigan
Published: December 2009

This article is dedicated to the research on a miniaturized W‐band multiplied phase‐locked frequency synthesizer. This module adopts microwave frequency synthesizer and multiplying scheme. It is composed of a C‐band phase‐locked loop (PLL) frequency synthesizer and a millimeter‐wave (mm‐wave) ×4 × 3 multiplier chain. Measurements show that the W‐band multiplied frequency synthesizer module covers 92.4–95.6 GHz with a minimal step of 40 MHz, low phase noise (better than −75 dBc/Hz@10 kHz in the whole output frequency band), sufficient power (−5.7 dBm to −3.6 dBm), and only a very compact size of 9.8 cm long ×9.5 cm wide ×2.7 cm high. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 412–416, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24915
Class F against tuned load configuration in Doherty power amplifiers
Authors: Colantonio P. , Giannini F. , Giofrè R. , Piazzon L.
Published: December 2009

The experimental results and comparison of two Doherty Power Amplifiers (DPAs) with the Main device designed respectively in a Tuned Load and a Class F configuration are presented. Both DPAs are designed by using GaN HEMT (1 mm of gate periphery) as active device to operate at 2.14 GHz, assuring an almost constant efficiency over the usual Output Back Off range of 6 dB. The experimental results demonstrate the benefit of the Class F solution in a DPA architecture. ©2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 450–452, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24918
A novel broadband VHF SiC MESFET class‐E high power amplifier
Authors: Chen Wenhua , Li Xiang , Wang Li , Feng Zhenghe , Xue Xing
Published: December 2009

Based on a Silicon carbide (SiC) Metal‐Semiconductor Field Effects Transistor (MESFET), a broadband VHF SiC class‐E high power amplifier is implemented by using a π‐transform output load network. Experimental results show that drain efficiency greater than 60% is achieved over a frequency bandwidth of 51.4%, and the peak output power exceeds 34 W. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 272–276, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24922
High‐level integrated passive triplexer and quintplexer module in organic SOP technology
Authors: Lim Sung Phyo , Park Jae Yeong
Published: December 2009

In this letter, fully embedded passive triplexer and quintplexer module into organic packaging substrate were presented for US CDMA handset applications. First, the passive triplexer was implemented by embedding all passive elements and circuits into multilayered organic packaging substrate. The passive triplexer circuit with eight passive elements was comprised of a diplexer, parallel resonator, and matching network. The size of the fabricated triplexer was 3 mm × 4 mm. The compact CDMA quintplexer module was fabricated by assembling the embedded passive triplexer with DCN and PCS duplexers on FR‐4 evaluation board. A fabricated quintplexer module exhibited an insertion loss of −2.2 dB/−2.9 dB at DCN Tx/Rx band, −3 dB/−2.7 dB at PCS Tx/Rx band, and −2.4 dB at GPS Rx band, respectively. In addition, the stop‐band attenuation is −40 dB/−44 dB at DCN Tx/Rx band, −55 dB/−45 dB at PCS Tx/Rx band, and −37 dB at GPS Rx band, respectively. Measured isolations in each Tx band are −62 dB/−58 dB at GPS/PCS of DCN band, −30 dB/−36 dB at DCN/PCS of GPS band, and −45 dB/−38 dB at DCN/GPS of PCS band. It is comparatively much higher than the matching circuit type quintplexer module, which indicates that the embedded triplexer is strongly applicable for improving the interferer blocking. The simulated performance characteristics were agreed with the simulated ones. ©2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 302–306, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24923
Retracted: Neural modeling for compact coplanar waveguide bandpass filter loaded split ring resonator
Authors: Liu Haiwen
Published: December 2009

The following article from Microwave and Optical Technology Letters, Volume 52, Issue 2, "Neural modeling for compact coplanar waveguide bandpass filter loaded split ring resonator" by Haiwen Liu, published online on December 8, 2009 in Wiley InterScience (www.interscience.wiley.com), has been retracted by the journal Editor‐in‐Chief, Kai Chang, and Wiley Periodicals, Inc. due to duplicate publication in the Journal of Infrared Millimeter and Terahertz Waves as a result of a communication misunderstanding.
Extinction ratio enhancement of self‐phase modulation based all‐optical regenerated signals in microstructured fibers
Authors: Zhang Xia , Ren Xiaomin , Zhao Naifeng , Wang Yamiao , Zheng Long , Huang Yongqing
Published: December 2009

All‐optical 2R regeneration of 10 Gb/s signals based on self‐phase modulation (SPM) in an 80‐m dispersion‐flattened microstructure fiber was demonstrated experimentally. The SPM‐induced broadened spectrum was generated in bandwidth of 70 nm with the flatness of −3 dB in the 1550 nm band. The output extinction ratio of the optimal regenerated signals was improved from 5.6 to about 12 dB. The regenerator also could greatly reduce the amplitude jitter. Furthermore, the single‐to‐multiple‐channel wavelength conversion characteristic of the regenerator was also discussed. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 347–351, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24927
A switchable dual‐wavelength all‐fiber laser based on Panda‐type photosensitive polarization‐maintaining erbium‐doped fiber
Authors: Liu Peng , Yan Fengping , Wang Chuncan , Zhang Fan , Liu Chu
Published: December 2009

A novel swithcable dual‐wavelength fiber laser using Panda‐type photosensitive polarization‐maintaining erbium‐doped fiber (PMEDF) is proposed and experimentally demonstrated. Based on the integration of good photosensitivity and gain characteristics, two matched uniform fiber Bragg gratings (FBGs) are directly written in the PMEDF as reflectors, an all‐fiber linear laser cavity with no splice in it is then obtained. Because of the high birefringence of the PMEDF, both of the FBGs show two reflection peaks corresponding to two orthogonal linear polarization modes. By adjusting the polarization controller (PC) in the cavity, three lasing outputs (single‐wavelength at 1554.552 nm, single‐wavelength at 1554.916 nm, and dual‐wavelength at both wavelengths) are observed, respectively. The alternate wavelength switching is flexible. Repeated testing results show that a high‐quality lasing output with side‐mode suppression ratio (SMSR) better than 50dB is achieved in all switching cases, the peak power of the laser either in single‐wavelength output or in dual‐wavelength output keeps stable with a small fluctuation less than 0.46 dB. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 386–389, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24928
Broadband transition between microstrip line and WR15 rectangular waveguide using low‐temperature cofired ceramic process
Authors: Lee Hong‐Yeol , Kim Young‐Goo , Jun Dong‐Suk , Choi Ik‐Guen , Park Kang‐Ho , Kim Jongdae
Published: December 2009

A compact aperture coupled patch type microstrip‐to‐waveguide transition at V‐band is proposed and fabricated using low‐temperature cofired ceramic process. It uses the aperture coupled microstrip feed and the parasitic patch antenna radiating into the waveguide to improve the insertion loss and the bandwidth. As a result of experiments, low‐transmission loss and high‐return loss are realized at the design frequency of 60 GHz. For a 10‐dB return loss, a relative bandwidth of 13.8% is obtained for a fabricated back‐to‐back transition. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 433–435, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24941
Low loss reflection‐type phase shifter in Ku band
Authors: Lambard T. , Lafond O. , Himdi M. , Jeuland H. , Bolioli S.
Published: December 2009

This article presents a Ku band 360° analogue phase shifter optimized with a genetic algorithm. Varactor diodes are used as the tuning elements. The device presents 360° phase shift on 11% bandwidth. At 12 GHz, the insertion loss is found to be −2.2 ± 0.4 dB. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 283–285, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24944
Compact band‐notched ultra‐wideband antenna using defected ground structure
Authors: Li Li‐Xian , Zhong Shun‐Shi , Chen Min‐Hua
Published: December 2009

A compact printed monopole ultra‐wideband (UWB) antenna with the band‐notched function is proposed. The antenna consists of a fan‐shaped metal patch and a trapeziform ground with a 50 Ω tapered coplanar waveguide (CPW) transmission line. By simply adjusting the length of the U‐shaped defected ground structure (DGS) in the ground plane, the band‐rejected filtering properties for the WLAN band is achieved. The proposed antenna is successfully simulated, designed, and measured, which shows an ultra‐wide matched impedance band from 3 to 15 GHz for VSWR ≤2 with a stop‐band of 5–6 GHz. The stable radiation patterns are also obtained. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 286–289, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24946
Critical coupling of a planar inverted F‐antenna using a ferrite sheet
Authors: Kim Hojeong , Choi Hyengcheul , Jeon Sinhyung , Kim Hyeongdong
Published: December 2009

In this letter, a novel method that can achieve critical coupling in a planar inverted F‐antenna of high height is proposed. Theproposed antenna can achieve critical coupling by attachment of a ferrite sheet without changing the size of the antenna or ground plane. A ferrite sheet is used to increase shunt inductance of the shorting pin loop. The proposed antenna is modeled by an equivalent circuit based on transmission line modeling. It has a very wide bandwidth of 16% for a voltage standing wave ratios <2. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 400–403, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24950
Simultaneous OTDM demultiplexing and data format conversion using A D flip‐flop
Authors: Xie Yiyuan , Zhang Jianguo , Xu Jiang
Published: December 2009

A D flip‐flop is used to simultaneously demultiplex and data format conversion a single 10 Gbits/s channel from a 20 Gbits/s optical time‐division multiplexed data stream. Error‐free demultiplexing was achieved at very low optical signal power: −14 dBm (20 Gbits/s). The proposed demultiplexer has a simple structure and achieves return‐to‐zero (RZ) to nonreturn‐to‐zero (NRZ) data format conversion. The demultiplexer allows monolithic integration. The proposed demultiplexer will become an important interface technology in future for connecting the ultra‐fast optical time division multiplexing (OTDM) long haul networks to the wavelength division multiplexing (WDM) access and metro networks. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 398–400, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24955
J‐compensated PGSE: an improved NMR diffusion experiment with fewer phase distortions
Authors: Torres Allan M. , Zheng Gang , Price William S.
Published: December 2009

Peak distortion caused by homonuclear 1H J‐coupling is a major problem in many spin‐echo‐based experiments such as pulsed gradient spin‐echo (PGSE) experiments. Although peak phase distortions can be lessened by the incorporation of anti‐phase purging sequences, the sensitivity is substantially decreased. Techniques for lessening the effect of homonuclear J‐coupling evolution in spin‐echo‐based experiments have been investigated. Two potentially useful candidates include a J‐compensated inversion sequence that is efficient over a wide range of J‐coupling values and a pulse sequence that refocuses homonuclear J‐evolution during the spin‐echo. The latter was found to work superbly on samples containing two spin (AX or AB) systems and still provided significant advantage over the standard method on samples containing more complicated spin systems. Implementation of this J‐refocusing technique into a PGSE‐type experiment (J‐PGSE) leads to dramatic improvement of spectra and easier data analysis. The J‐PGSE sequence should find applications in many diffusion studies where the PGSE‐type method is required and should be a viable alternative to PGSTE especially in dilute samples due to its enhanced sensitivity. Copyright © 2009 John Wiley & Sons, Ltd.
Genetic modification of pigs as organ donors for xenotransplantation
Authors: Klymiuk Nikolai , Aigner Bernhard , Brem Gottfried , Wolf Eckhard
Published: December 2009

Transgenic pigs are promising donor organisms for xenotransplantation as they share many anatomical and physiological characteristics with humans. The most profound barrier to pig‐to‐primate xenotransplantation is the rejection of the grafted organ by a cascade of immune mechanisms commonly referred to as hyperacute rejection (HAR), acute humoral xenograft rejection (AHXR), immune cell‐mediated rejection, and chronic rejection. Various strategies for the genetic modification of pigs facilitate tailoring them to be donors for organ transplantation. Genetically modified pigs lacking alpha‐1,3‐Gal epitopes, the major xenoantigens triggering HAR of pig‐to‐primate xenografts, are considered to be the basis for further genetic modifications that can address other rejection mechanisms and incompatibilities between the porcine and primate blood coagulation systems. These modifications include expression of human complement regulatory proteins, CD39, endothelial protein C receptor, heme oxygenase 1, thrombomodulin, tissue factor pathway inhibitor as well as modulators of the cellular immune system such as human TNF alpha‐related apoptosis inducing ligand, HLA‐E/beta‐2‐microglobulin, and CTLA‐4Ig. In addition, transgenic strategies have been developed to reduce the potential risk of infections by endogenous porcine retroviruses. The protective efficacy of all these strategies is strictly dependent on a sufficiently high expression level of the respective factors with the required spatial distribution. This review provides an overview of the transgenic approaches that have been used to generate donor pigs for xenotransplantation, as well as their biological effects in in vitro tests and in preclinical transplantation studies. A future challenge will be to combine the most important and efficient genetic modifications in multi‐transgenic pigs for clinical xenotransplantation. Mol. Reprod. Dev. 77: 209–221, 2010. © 2009 Wiley‐Liss, Inc.
Analytical solution for the response of a flexible retaining structure with an elastic backfill
Authors: Jung Chulmin , Bobet Antonio , Fernández Gabriel
Published: December 2009

An extension of an existing analytical solution for the response of a flexible retaining wall subjected to seismic loading is presented. The solution is based on the assumption that the wall and the soil remain elastic and that there are no shear stresses at the wall–soil interface while the contact remains tied. In addition to the wall displacements due to bending, the wall can experience rigid‐body motions due to rotation and horizontal and vertical movements. The solution is verified by comparing its results with those of a finite element method. Results from the analytical solution together with those of the (FEM) are used to identify and quantify the relative importance of key parameters on the seismic response of a wall. The study shows that wall flexibility and horizontal rigid‐body motions of the wall and frequency content of the seismic input have a significant effect on the wall loads. The pressures behind a rigid wall decrease as the wall rotates about its base, whereas for a flexible wall, the soil pressures decrease as the friction between the backfill and the wall increases. The rigid‐body vertical movements of a wall have little impact on the dynamic pressures induced in the wall, except for a flexible wall where, when prevented, the dynamic loads may be reduced. Copyright © 2009 John Wiley & Sons, Ltd.
Isothermal differential scanning calorimetry study of a glass/epoxy prepreg
Authors: Hayaty Mehran , Beheshty Mohammad Hosain , Esfandeh Masoud
Published: December 2009

Isothermal differential scanning calorimetry (DSC) was used to study the curing behavior of epoxy prepreg Hexply®1454 system, based on diglycidyl ether of bisphenol A (DEGBA)/dicyandiamid (DICY) reinforced by glass fiber. Cure kinetics of an autocatalytic‐type reaction were analyzed by general form of conversion‐dependent function. The characteristic feature of conversion‐dependent function was determined using a reduced‐plot method where the temperature‐dependent reaction rate constant was analytically separated from the isothermal data. An autocatalytic kinetic model was used; it can predict the overall kinetic behavior in the whole studied cure temperature range (115–130°C). The activation energy and pre‐exponential factor were determined as: E = 94.8 kJ/mol and A = 1.75 × 1010 sec−1 and reaction order as 2.11 (m + n = 0.65 + 1.46 = 2.11). A kinetic model based on these values was developed by which the prediction is in good agreement with experimental values. Copyright © 2009 John Wiley & Sons, Ltd.
Central nervous system involvement at the time of presentation in acute promyelocytic leukemia
Authors: Collins Chelsea , Knoderer Holly
Published: December 2009

Central nervous system (CNS) involvement is rarely observed in acute promyelocytic leukemia (APML). Most cases of CNS involvement occur at relapse rather than at presentation. Because of the extremely low incidence of CNS disease, diagnostic lumbar puncture is not routinely required and prophylactic intrathecal chemotherapy is not routinely administered. Here, we describe a teenage patient with newly diagnosed APML, chloromas, and symptomatic CNS involvement confirmed by MRI and cerebrospinal fluid (CSF) findings. Pediatr Blood Cancer © 2009 Wiley‐Liss, Inc.
Spontaneous tumor lysis syndrome in a child with T‐cell acute lymphoblastic leukemia
Authors: Kobayashi Daisuke , Wofford Marcia M. , McLean Thomas W. , Lin Jen‐Jar
Published: December 2009

We report a 5‐year‐old female who presented with unexplained acute renal failure (ARF) and hyperuricemia and who was subsequently diagnosed of T‐cell acute lymphoblastic leukemia (ALL). Peripheral smear was initially unremarkable. She required hemodialysis. Two weeks later, peripheral smear showed 40% blasts and bone marrow demonstrated T‐cell ALL. Our case was the fifth and the youngest case of ALL with spontaneous tumor lysis syndrome. However, in contrast to previous reports in ALL or acute myeloid leukemia, our patient did not have blasts noted on periphereal blood smear and her white blood cell count and serum lactate dehydrogenase level were normal on admission, a time when dialysis‐dependent ARF and severe hyperuricemia were present. Occult hematologic malignancy should be considered in cases of ARF and hyperuricemia of unknown etiology even when peripheral hematologic findings are not informative. Pediatr Blood Cancer 2010;54:773–775. © 2009 Wiley‐Liss, Inc.
Pancreatic tumors in children and adolescents: The Italian TREP project experience
Authors: Dall'Igna Patrizia , Cecchetto Giovanni , Bisogno Gianni , Conte Massimo , Chiesa Pierluigi Lelli , D'Angelo Paolo , De Leonardis Francesco , De Salvo Gianluca , Favini Francesca , Ferrari Andrea ,   on Behalf of the TREP Group
Published: December 2009

Introduction

Malignant pancreatic tumors are exceedingly rare in pediatric age and their clinical features and treatment usually go unappreciated by most pediatric oncologists and surgeons.

Methods

From January 2000 to July 2009, 21 patients <18 years old with pancreatic tumors were prospectively registered in the Italian cooperative TREP project dedicated to very rare pediatric tumors.

Results

Tumor types were 4 pancreatoblastomas, 2 pancreatic carcinomas, 3 neoplasms of the endocrine pancreas, and 12 solid pseudopapillary tumors. Three of the four patients with pancreatoblastoma had advanced disease at diagnosis and were given chemotherapy; at the time of this report, three patients were alive in first remission, while one died due to treatment toxicity. Both the cases of pancreatic carcinoma had the acinar cell subtype and successfully underwent pancreaticoduodenectomy with complete tumor resection, remaining without evidence of disease at the time of this analysis. The histological diagnoses of the three endocrine tumors were a malignant islet cell tumor, a gastrinoma, and a well‐differentiated tumor. All 12 patients with solid pseudopapillary tumors underwent complete tumor resection and were given no adjuvant treatment; 11 were alive in first remission, while one experienced a local and distant relapse 5 years after diagnosis.

Conclusions

Surgery remains the keystone of treatment for pancreatic tumors in pediatric age as in adults. The TREP project shows that prospective cooperative studies are feasible even for such very rare tumors as these and may serve as a model for developing international cooperative schemes. Pediatr Blood Cancer 2010;54:675–680. © 2009 Wiley‐Liss, Inc.
Synthesis and characterization of perfluorinated arylenevinylene polymers
Authors: Cardone Antonio , Martinelli Carmela , Pinto Vita , Babudri Francesco , Losurdo Maria , Bruno Giovanni , Cosma Pinalysa , Naso Francesco , Farinola Gianluca M.
Published: December 2009

Fully fluorinated arylenevinylene polymers have been synthesized via a methodology based on the Stille cross‐coupling reaction and characterized by FTIR spectroscopy and MALDI‐TOF mass spectrometry. Investigation of thin film properties by cyclic voltammetry and ellipsometry shows that complete substitution of hydrogen atoms with fluorine atoms on the conjugated backbone of the poly(arylenevinylene)s results in a strong increase of the band gap. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 285–291, 2010
Study on incomplete fluorescence quenching of cationic poly(p‐phenylenevinylene)s with different contents of cis‐ and trans‐vinylic linkages
Authors: Zhang Guang‐Wei , Lu Xiao‐Mei , Fan Qu‐Li , Huang Yan‐Qin , Huang Wei
Published: December 2009

Fluorescence properties of a series of cationic poly(p‐phenylenevinylene) (PPV) derivatives with different contents of cis‐ and trans‐vinylic linkages quenched by Fe(CN) were intensively investigated. PPVs with cis‐/trans‐vinylic linkages display downward Stern‐Volmer curves indicating incomplete quenching. The fluorescence quenching mechanism and the effect of many factors possible on the incomplete quenching has been examined, and the difference of the quenching behavior of two isomers was investigated, which further confirmed that the presence of cis‐vinylic linkages would most probably cause inaccessible fluorophores and thus the incomplete quenching. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010
Macromolecular brushes synthesized by “grafting from” approach based on “click chemistry” and RAFT polymerization
Authors: Wu Dongxia , Song Xiaohui , Tang Tao , Zhao Hanying
Published: December 2009

Well‐defined macromolecular brushes with poly(N‐isopropyl acrylamide) (PNIPAM) side chains on random copolymer backbones were synthesized by “grafting from” approach based on click chemistry and reversible addition‐fragmentation chain transfer (RAFT) polymerization. To prepare macromolecular brushes, two linear random copolymers of 2‐(trimethylsilyloxy)ethyl methacrylate (HEMA‐TMS) and methyl methacrylate (MMA) (poly(MMA‐co‐HEMA‐TMS)) were synthesized by atom transfer radical polymerization and were subsequently derivated to azide‐containing polymers. Novel alkyne‐terminated RAFT chain transfer agent (CTA) was grafted to polymer backbones by copper‐catalyzed 1,3‐dipolar cycloaddition (azide‐alkyne click chemistry), and macro‐RAFT CTAs were obtained. PNIPAM side chains were prepared by RAFT polymerization. The macromolecular brushes have well‐defined structures, controlled molecular weights, and molecular weight distributions (Mw/Mn ≦ 1.23). The RAFT polymerization of NIPAM exhibited pseudo‐first‐order kinetics and a linear molecular weight dependence on monomer conversion, and no detectable termination was observed in the polymerization. The macromolecular brushes can self‐assemble into micelles in aqueous solution. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 443–453, 2010
Synthesis and characterization of hyperbranched polystyrene via click reaction of AB2 macromonomer
Authors: Kong Li‐Zhi , Sun Miao , Qiao Hua‐Ming , Pan Cai‐Yuan
Published: December 2009

Well‐defined hyperbranched polystyrenes have been successfully prepared by polymerization of AB2 macromonomer, polystyrene containing an azide group at its one end and two terminal propargyl groups at the other end via click reaction. For preparation of AB2 macromonomers, an ATRP initiator, bispropargyl 2‐bromosuccinate (BPBS) with two propargyl groups and one bromine group was synthesized by the successive bromination and esterification reaction of L‐aspartic acid. The resulting BPBS initiated the ATRP of St, and subsequently, the terminal bromine groups of (CH≡C)2‐PS‐Brs were substituted by N3 via the reaction with sodium azide resulting the AB2 macromonomer, (CH≡C)2‐PS‐N3 with various molecular weights. All intermediates and the resultant polymers were characterized by GPC, 1H NMR, FTIR, and MALLS methods. The polymerization kinetics study showed fast increase of DP at the initial stage of polymerization and then slow increase of their DP. The final “HyperMacs” have high‐molecular weight up to Mw,MALLS = 340,000 g/mol, their molecular weight distributions were moderately narrow (Mw/Mn = 1.47–1.65). The ratios of [η]H/[η]L of the HyperMacs formed in the polymerization system increased with evolution of polymerization. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 454–462, 2010
Surface adsorption‐induced conformational ordering and crystallization of polyethylene oxide
Authors: Geng Yong , Wang Guanglin , Cong Yuanhua , Bai Liangui , Li Liangbin , Yang Chuanlu
Published: December 2009

The conformational ordering and crystallization of polyethylene oxide (PEO) in the presence of KBr surface were studied with in situ Fourier transform infrared spectroscopy (FTIR). KBr was chosen because of its low absorption on IR, which allows adding large amounts KBr into PEO matrix without sacrificing IR signal significantly. The presence of KBr enhances conformational order well above the melting temperature of PEO, which can further accelerate or decelerate the crystallization process. Low concentrations of KBr powder in the PEO melt promotes crystallization process, whereas high concentration of KBr restricts large portion of PEO chains on KBr surfaces, which hinder the diffusion and rearrangement of conformation and consequently slow down the crystallization process. Acceleration of crystallization requires a synergetic effect between the adsorbed chains with ordered conformation and the free chains with a fast diffusion rate, where the former and the later are responsible to lower the nuclei barrier and to maintain the low activation energy of diffusion, respectively. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 48: 106–112, 2010
Shear‐induced structuring kinetics in thermoplastic segmented polyurethanes monitored by rheological tools
Authors: Mourier Elise , Fulchiron René , Méchin Françoise
Published: December 2009

Thermoplastic segmented polyurethanes (TPUs) are an important class of thermoplastic elastomers with a two‐phase microstructure arising from the thermodynamic incompatibility between hard (HSs) and soft segments. This microphase separation observed on cooling from a homogeneous state is often combined with the solidification of either or both types of segments. In this study, the structuring mechanism of two TPUs with HSs based on 4,4′‐diphenylmethane diisocyanate and 1,4‐butanediol was investigated from rheological measurements. Hence, in addition to the structuring temperature influence, the effect of an applied preshear flow in the melt polymer was analyzed, in particular. The results clearly show an enhancement of the solidification kinetics by the preshear. Indeed, the measured structuring time can be reduced by more than 1 decade. Rheo‐optical microscopy observations coupled with a shearing hot stage corroborated these results and showed the modification of the microstructure by the shear. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 48: 190–201, 2010
Classification of patterned ground based on morphometry and site characteristics: a case study from the High Sudetes, Central Europe
Authors: Treml Vaclav , Krizek Marek , Engel Zbynek
Published: December 2009

About 750 examples of patterned ground forms at 25 sites in the High Sudetes mountains (Czech Republic) were classified using morphometric characteristics and environmental parameters. Simple parameters such as length, width and height of patterned ground were measured in the field, with additional variables of elevation, intensity of deflation and regolith grain size. The surface morphometry of patterned ground, comprising relict sorted polygons and sorted nets and active earth hummocks, was strongly influenced by site characteristics. Sorted net dimensions were affected by the intensity of deflation, which determined the micro‐relief (positive correlation), and regolith coarseness, which negatively impacted the diameter of landforms. For sorted polygons, opposite relations concerning diameter and regolith coarseness were observed. The use of both morphometric and environmental variables within canonical linear discriminant analysis was successful in classifying almost 95 per cent of landforms. The advantage of combining the two types of predictors was demonstrated by the presence of both earth hummocks and sorted polygons at wind‐swept sites, but with significantly different morphometric and regolith requirements. Copyright © 2009 John Wiley & Sons, Ltd.
The impact of HMG‐CoA reductase therapy on serum PSA
Authors: Mener David J. , Cambio Angelo , Stoddard David G. , Martin Brad A. , Palapattu Ganesh S.
Published: December 2009

BACKGROUND

3‐hydroxy‐3‐methyl‐glutaryl‐CoA (HMG‐CoA) reductase inhibitors, otherwise known as statins, inhibit the enzyme that controls the conversion of HMG‐CoA to mevalonate, a precursor for cholesterol. Statins may be important to prostate cancer biology by inhibiting cell growth, inflammation, and oxidative stress. The purpose of this study was to assess the influence of statin therapy on serum prostate‐specific antigen (PSA) levels.

METHODS

The computerized medical records at the University of Rochester Medical Center were used to identify men who filled statin prescriptions between May 31st, 2008 and September 30th, 2008. Men with at least one PSA assay performed within 2 years before and at least one PSA assay performed within 1 year after starting a statin medication were included. The primary endpoint was the change in PSA concentration computed as the difference between PSA levels before and after starting a statin medication. Paired t‐tests were used to analyze the mean differences in PSA values.

RESULTS

A total of 962 patients were identified. The mean difference in serum PSA level after statin administration was −0.29 ng/ml (−8.04%). Subgroup analyses for mean PSA concentration change before and after statin administration by age group revealed: 50–59 years old (−0.1609, 95% CI: −0.2444, −0.0775, P < 0.0002), 60–69 years old (−0.3393, 95% CI: −0.4641, −0.2145, P < 0.0001), and >70 years old (−0.351, 95% CI: −0.490, −0.212, P < 0.0001).

CONCLUSIONS

These observations suggest a statistically significant reduction in serum PSA level that is associated with the onset of statin therapy. Prostate 70: 608–615, 2010. © 2009 Wiley‐Liss, Inc.