bluuebunny/crossref_metadata_2025 huggingface dataset:
Enantioselective Total Synthesis of Brevetoxin A: Unified Strategy for the B, E, G, and J Subunits
Authors: Crimmins Michael T. , Ellis J. Michael , Emmitte Kyle A. , Haile Pamela A. , McDougall Patrick J. , Parrish Jonathan D. , Zuccarello J. Lucas
Published: July 2009

Brevetoxin A is a decacyclic ladder toxin that possesses 5‐, 6‐, 7‐, 8‐, and 9‐membered oxacycles, as well as 22 tetrahedral stereocenters. Herein, we describe a unified approach to the B, E, G, and J rings based upon a ring‐closing metathesis strategy from the corresponding dienes. The enolate technologies developed in our laboratory allowed access to the precursor acyclic dienes for the B, E, and G medium‐ring ethers. The strategies developed for the syntheses of these four monocycles ultimately provided multigram quantities of each of the rings, supporting our efforts toward the completion of a convergent synthesis of brevetoxin A.
Unsteady fluid–solid interaction by a kernel‐based particle method
Authors: Ostad H. , Mohammadi S.
Published: July 2009

A Lagrangian stabilized particle method is adopted for the simulation of unsteady fluid flow and gas dynamics. The velocity field smoothing technique, which was successfully implemented for reducing zero energy modes and tensile instabilities in solid problems, is used for the stabilization of the fluid phase. In this method a smoothing technique has been applied and the field values in particles are prevented from excessive jumps due to instability. This approach can replace traditional stabilization methods such as the artificial viscosity approach. In this paper, the corrective smoothed particle method has been implemented for solving governing partial differential equations of fluid. Also a modification in basic governing equations is performed on boundary interfaces to conserve mass and energy quantities. The method is implemented and verified in one‐ and two‐dimensional compressible flow problems. Copyright © 2009 John Wiley & Sons, Ltd.
Multipath effects and adaptive transmission in presence of indoor power line background noise
Authors: Tiru Banty , Boruah P. K.
Published: July 2009

The paper studies the background noise characteristics of a typical indoor power line (PL) in India. The noise decreases rapidly with frequency and can be considered as white beyond 5 MHz. The time variation of the background noise at every frequency in the non‐white region is modeled and compared in different environments which include laboratory and factory setups. In all cases, the background noise can be modeled by density functions related to multipath fading i.e. Nakagami‐m, Rayleigh and Rician. Fading is worse than the Rayleigh fading when the PL network has more connected loads and impedance discontinuities. Single frequency noise shows Rician fading when the background noise is narrowband Gaussian. The results are compared with those obtained in other countries in an attempt to check the validity of the model worldwide. A PL channel noise simulator is developed using the density functions to simulate the background noise. A technique is proposed that adapts the carrier frequency according to the channel property at a particular instant. The performance of such a system is tested in a simulated environment and shows that the method enables transmission of signals at very low transmission power compared with that in the AWGN channel. Copyright © 2009 John Wiley & Sons, Ltd.
Daily and developmental modulation of “premotor” activity in the birdsong system
Authors: Day Nancy F. , Kinnischtzke Amanda K. , Adam Murtaza , Nick Teresa A.
Published: July 2009

Human speech and birdsong are shaped during a sensorimotor sensitive period in which auditory feedback guides vocal learning. To study brain activity as song learning occurred, we recorded longitudinally from developing zebra finches during the sensorimotor phase. Learned sequences of vocalizations (motifs) were examined along with contemporaneous neural population activity in the song nucleus HVC, which is necessary for the production of learned song (Nottebohm et al. 1976: J Comp Neurol 165:457–486; Simpson and Vicario 1990: J Neurosci 10:1541–1556). During singing, HVC activity levels increased as the day progressed and decreased after a night of sleep in juveniles and adults. In contrast, the pattern of HVC activity changed on a daily basis only in juveniles: activity bursts became more pronounced during the day. The HVC of adults was significantly burstier than that of juveniles. HVC bursting was relevant to song behavior because the degree of burstiness inversely correlated with the variance of song features in juveniles. The song of juveniles degrades overnight (Deregnaucourt et al. 2005: Nature 433:710–716). Consistent with a relationship between HVC activity and song plasticity (Day et al. 2008: J Neurophys 100:2956–2965), HVC burstiness degraded overnight in young juveniles and the amount of overnight degradation declined with developmental song learning. Nocturnal changes in HVC activity strongly and inversely correlated with the next day's change, suggesting that sleep‐dependent degradation of HVC activity may facilitate or enable subsequent diurnal changes. Collectively, these data show that HVC activity levels exhibit daily cycles in adults and juveniles, whereas HVC burstiness and song stereotypy change daily in juveniles only. In addition, the data indicate that HVC burstiness increases with development and inversely correlates with song variability, which is necessary for trial and error vocal learning. © 2009 Wiley Periodicals, Inc. Develop Neurobiol, 2009
Broad categories for the diagnosis of eating disorders (BCD‐ED): An alternative system for classification
Authors: Walsh B. Timothy , Sysko Robyn
Published: July 2009

Objective:

Eating Disorder Not Otherwise Specified (EDNOS), a residual category in DSM‐IV, is the most commonly used eating disorder diagnosis in clinical settings. A diagnostic scheme, termed Broad Categories for the Diagnosis of Eating Disorders (BCD‐ED), is proposed to diminish use of the EDNOS category while preserving the existing eating disorder categories. The objective of this review was to examine the advantages and disadvantages of adopting this scheme for DSM‐V.

Method:

We reviewed published studies to assess the proportion of individuals with DSM‐IV EDNOS that would be reclassified under the BCD‐ED system, support for the hierarchy of the three categories, and the potential risk of “overdiagnosis.”

Results:

Adopting the BCD‐ED scheme would have both advantages and disadvantages, but would likely substantially reduce the number of individuals who would receive an EDNOS diagnosis.

Discussion:

BCD‐ED is a potential method of addressing the high frequency of EDNOS, but would be a major change in how eating disorders are categorized. © 2009 American Psychiatric Association. Int J Eat Disord 2009
Clarifying criteria for cognitive signs and symptoms for eating disorders in DSM‐V
Authors: Becker Anne E. , Eddy Kamryn T. , Perloe Alexandra
Published: July 2009

Objective:

This article reviews literature relevant to challenges in clinical ascertainment of cognitively‐based diagnostic criteria of anorexia nervosa (AN) and bulimia nervosa (BN) to examine whether revision might enhance their clinical utility.

Method:

We performed a systematic literature search to identify publications relevant to clinical evaluation of cognitive symptoms of AN and BN.

Results:

The literature supports several reasons that individuals with an eating disorder may not endorse cognitive symptoms, despite their presence. These include limited insight, minimization, or denial, as well as intentional concealment related to perceived stigma, social desirability, or investment in maintaining behavioral symptoms. We also identified reasons that the word “refusal” in AN criterion A may render its application problematic.

Discussion:

We conclude that specific guidance for ascertainment of cognitive signs for AN and BN in the absence of patient disclosure or endorsement, longitudinal evaluation, and/or collateral data may improve clinical utility of these diagnostic criteria. © 2009 American Psychiatric Association. Int J Eat Disord 2009
(Cyclopentadienyl)nitrosylmanganese Compounds: The Original Molecules Containing Bridging Nitrosyl Groups
Authors: Yan Bing , Xie Yaoming , King R. Bruce , Schaefer Henry F.
Published: July 2009

The (cyclopentadienyl)nitrosylmanganese derivatives Cp2Mn2(NO)2(CO)n (n = 2, 1, 0), Cp2Mn2(NO)3X (X = NO2, ‐C5H5), CpMn(NO)2, Cp2Mn2(NO)4, and Cp3Mn3(NO)4 have been investigated by using density functional theory. Six structures are found for Cp2Mn2(NO)2(CO)2 with various combinations of terminal and bridging carbonyl and nitrosyl groups within ca. 3 kcal/mol of each other indicating a highly fluxional system. A triplet‐state triply bridged structure is predicted to be the global minimum for Cp2Mn2(NO)2(CO), just as it is for the isoelectronic Cp2Fe2(CO)3. For Cp2Mn2(NO)2 a doubly bridged triplet structure is predicted to lie ca. 30 kcal/mol below the corresponding singlet structure, unlike the isoelectronic Cp2Fe2(CO)2. The structures predicted for Cp2Mn(µ‐NO)2(NO)X (X = NO2 and η1‐C5H5) and Cp3Mn3(µ‐NO)3(µ3‐NO) are close to the experimentally known structures. The monomer CpMn(NO)2, with a favorable 18‐electron configuration for the manganese atom, is predicted to be unstable with respect to dimerization to Cp2Mn2(µ‐NO)2(NO)2, for which two structures are found of similar energy. One Cp2Mn2(µ‐NO)2(NO)2 structure has a non‐bonding Mn···Mn distance of ca. 3.1 Å and linear terminal MnNO units, whereas the other Cp2Mn2(µ‐NO)2(NO)2 structure has a single‐bond Mn–Mn distance of ca. 2.5 Å and bent terminal MnNO units. In Cp2Mn(µ‐NO)2(NO)(η1‐Cp) the Mn2(µ‐NO)2 unit is unsymmetrical, with significantly different (by ca. 0.2 Å) Mn–N bond lengths to each side. However, in Cp2Mn2(NO)2(CO)n (n = 2, 1, 0) and Cp2Mn2(µ‐NO)2(NO)2 the Mn2(µ‐NO)2 units are symmetrical, with essentially the same Mn–N bond lengths to both sides. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Investigation of a dual CD chiral CE system for separation of glitazone compounds
Authors: Jamali Babak , Bjørnsdottir Inga , Cornett Claus , Honoré Hansen Steen
Published: July 2009

A dual CD‐CE method for chiral separation of enantiomers of pioglitazone, rosiglitazone and balaglitazone was investigated for the purpose of optimizing the chiral separation. In a previous work a dual CD chiral CE method was used for investigation of glitazone compounds in drug substance and pharmaceutical formulation and the studies showed that all studied glitazones were racemic mixtures. This CE method could separate the enantiomers with a resolution (RS) of about 3. However, another study on single glitazone enantiomers pointed out that a higher RS is needed to achieve more accurate results for separation of a small amount of one enantiomer in the presence of a high amount of the other enantiomers. The focus of this investigation was thus directed toward the effect of CDs and the pH of the running buffer to achieve a better enantioseparation. Initially CE systems with each of heptakis(2,6‐di‐O‐methyl)‐β‐CD (DM‐β‐CD) and heptakis(6‐sulfobutylether)‐β‐CD (SB‐β‐CD) as single CD added were investigated at three different pH values (2.5, 5.0 and 9.3). After having chosen the best of these three pH values a dual CD system was further investigated and optimized. The optimization work was then focused on the concentration of the two CDs and the pH of the running buffer and was performed using factorial design experiments. A mixture of a DM‐β‐CD and SB‐β‐CD was found to be optimal and necessary to achieve enantioseparation with sufficiently high RS. In order to further verify the importance of the SB‐β‐CD, a CE system with the DM‐β‐CD added and substitution or partial substitution of the SB‐β‐CD by SDS was studied for comparison. 1H‐NMR studies were performed to get a more detailed understanding of the interactions between the glitazones and the CDs used.The optimized dual CD‐CE method for chiral separation of the enantiomers of pioglitazone, rosiglitazone and balaglitazone using a running buffer containing 50 mM borate buffer pH 9.7, 12 mM of SB‐β‐CD and 3 mM of DM‐β‐CD provided a high RS (RS between 5.5 and 8.8).
Combined use of chiral ionic liquid and cyclodextrin for MEKC: Part I. Simultaneous enantioseparation of anionic profens
Authors: Wang Bin , He Jun , Bianchi Victoria , Shamsi Shahab A.
Published: July 2009

The enantiomers of five profen drugs were simultaneously separated by MEKC with the combined use of 2,3,6‐tri‐O‐methyl‐β‐cyclodextrin and chiral cationic ionic liquid, N‐undecenoxy‐carbonyl‐L‐leucinol bromide, which formed micelles in aqueous buffers. Enantioseparations of these profen drugs were optimized by varying the chain length and concentration of the IL surfactant using a standard recipe containing 35 mM 2,3,6‐tri‐O‐methyl‐β‐cyclodextrin, 5 mM sodium acetate at pH 5.0. The batch‐to‐batch reproducibility of N‐undecenoxy‐carbonyl‐L‐leucinol bromide was tested and found to have no significant impact in terms of enantiomeric resolution, efficiency, and migration time. Finally, this method was successfully applied for the quantitative determination of ibuprofen in pharmaceutical tablets.
Gold nanoparticle‐enhanced capillary electrophoresis‐chemiluminescence assay of trace uric acid
Authors: Zhao Shulin , Lan Xuehua , Liu Yi‐Ming
Published: July 2009

A sensitive method based on gold nanoparticle‐enhanced CE‐chemiluminescence (CL) detection was developed for quantifying uric acid (UA) in serum. In this work, gold nanoparticles were added into the running buffer of CE to catalyze the post‐column CL reaction between luminol and hydrogen peroxide, achieving highly efficient CL emission. Negative peaks were produced due to the inhibitory effects on CL emission from UA eluted from the electrophoretic capillary. The decrease in CL intensity was proportional to the concentration of UA in the range of 2.5×10−7–1.0×10−5 M. Detection limit was 4.6×10−8 M UA. Ten human serum samples were analyzed by the presented method. Serum level of UA was found to be in the range from 204 to 324 μM for healthy subjects (n=5), and from 464 to 497 μM for diabetic patients (n=5). The two groups were significantly different (p<0.05). The results suggested a potential application of the proposed assay in rapid primary diagnosis of diseases such as diabetes.
Complexity of resilient network optimisation
Authors: Żotkiewicz Mateusz , Pióro Michał , Tomaszewski Artur
Published: July 2009

Path restoration (PR) is one of the basic mechanisms for securing telecommunication networks against failures. In the paper, we discuss the complexity of certain variants of a multi‐commodity flow network optimisation problem in directed graphs related to state‐independent path restoration mechanisms. We demonstrate that most variants of the considered problem are $\cal{NP}$‐hard. Depending on the variant, we show how the problem can be reduced either from the partition problem or from the problem of finding an arc‐disjoint pair of paths that connect two distinct pairs of nodes. We also demonstrate that at the same time the considered problem is difficult to approximate. The complexity results of the paper are important as they can help to devise proper algorithms for resilient network design tools. Copyright © 2009 John Wiley & Sons, Ltd.
Persistence in some energy futures markets
Authors: Cunado Juncal , Gil‐Alana Luis A. , Perez de Gracia Fernando
Published: July 2009

In this study, we examine the possibility of long‐range dependence in some energy futures markets for different maturities. In order to test for persistence, we use a variety of techniques based on non‐parametric, semi‐parametric and parametric methods. The results indicate that there is little or no evidence of long memory in gasoline, propane, oil and heating oil at different maturities. However, when we focus on the volatility process, proxied by the absolute returns, we find strong evidence of long memory in all the variables at different contracts. © 2009 Wiley Periodicals, Inc. Jrl Fut Mark 30:490–507, 2010
Size clustering in the FTSE100 index futures market
Authors: ap Gwilym Owain , Meng Lei
Published: July 2009

Recent literature has begun to explore size clustering in financial markets. If a market is perfectly liquid, traders should be able to trade the exact amount that they desire; however, the presence of size clustering may prevent them from achieving optimal trade sizes. This study is novel in its investigation of size clustering in a futures market. We find that trade sizes cluster in a manner that is similar to the pattern of price clustering found in many financial markets. Importantly, we identify a trade‐off between size resolution and price resolution. We also find that the number of distinct trade sizes increases with trade frequency and with intra‐day volatility, and increases at the end of each calendar quarter. © 2009 Wiley Periodicals, Inc. Jrl Fut Mark 30:432–443, 2010
Noninvasive optical measures of CBV, StO2, CBF index, and rCMRO2 in human premature neonates' brains in the first six weeks of life
Authors: Roche‐Labarbe Nadège , Carp Stefan A. , Surova Andrea , Patel Megha , Boas David A. , Grant P. Ellen , Franceschini Maria Angela
Published: July 2009

With the causes of perinatal brain injuries still unclear and the probable role of hemodynamic instability in their etiology, bedside monitoring of neonatal cerebral hemodynamics with standard values as a function of age are needed. In this study, we combined quantitative frequency domain near infrared spectroscopy (FD‐NIRS) measures of cerebral tissue oxygenation (StO2) and cerebral blood volume (CBV) with diffusion correlation spectroscopy (DCS) measures of a cerebral blood flow index (CBFix) to test the validity of the CBV‐CBF relationship in premature neonates and to estimate cerebral metabolic rate of oxygen (rCMRO2) with or without the CBFix measurement. We measured 11 premature neonates (28–34 weeks gestational age) without known neurological issues, once a week from one to six weeks of age. In nine patients, cerebral blood velocities from the middle cerebral artery were collected by transcranial Doppler (TCD) and compared with DCS values. Results show a steady decrease in StO2 during the first six weeks of life while CBV remains stable, and a steady increase in CBFix. rCMRO2 estimated from FD‐NIRS remains constant but shows wide interindividual variability. rCMRO2 calculated from FD‐NIRS and DCS combined increased by 40% during the first six weeks of life with reduced interindividual variability. TCD and DCS values are positively correlated. In conclusion, FD‐NIRS combined with DCS offers a safe and quantitative bedside method to assess CBV, StO2, CBF, and rCMRO2 in the premature brain, facilitating individual follow‐up and comparison among patients. A stable CBV‐CBF relationship may not be valid for premature neonates. Hum Brain Mapp, 2010. © 2009 Wiley‐Liss, Inc.
Implications of CA3 NMDA and opiate receptors for spatial pattern completion in rats
Authors: Kesner Raymond P. , Warthen Danielle K.
Published: July 2009

Theoretical models of the CA3 suggest that because of its architecture, it mediates spatial pattern completion and working memory processes. The aim of this study was to determine whether with the use of drugs to block neurotransmitter action in CA3 one can separate the operation of these two processes using a visual–spatial pattern completion task for multiple cues. Rats were trained on a cheeseboard apparatus with a black curtain containing four extramaze cues. In the study phase rats removed a black block from one of 15 food wells and then after a 10‐ or 30‐s delay in the test phase they had to return to the food well in the absence of the black block. After reaching criterion performance cannulae were bilaterally implanted into the CA3 of the rats. Rats were then given AP5, naloxone, or phosphate buffered saline (PBS) and following the standard study phase they were given the test phase with 0, 1, 2, 3, or 4 cues removed. The mean degree of error in all drugs and all cue conditions was recorded. Overall spatial inaccuracy was recorded in rats under the AP5 30‐s delay condition, whereas deficits were contingent upon the number of cues available under all naloxone conditions. Results show that the blockage of glutamate via AP5 inhibited short‐term or working memory, whereas the blockage of mu‐opioids via naloxone disrupted visual–spatial pattern completion. © 2009 Wiley‐Liss, Inc.
Metabolic activity in the brain of juvenile and adult rats with a neonatal ventral hippocampal lesion
Authors: François Jennifer , Koning Estelle , Ferrandon Arielle , Sandner Guy , Nehlig Astrid
Published: July 2009

Longitudinal studies on patients for schizophrenia suggest that functional brain perturbations precede the onset of symptoms. Rats with a neonatal ventral hippocampal lesion (NVHL) are considered as a heuristic neurodevelopmental model of schizophrenia. We characterized basal metabolic changes observed in NVHL rats before and after the age when known behavioral alterations have been reported. Male pups were lesioned with ibotenic acid at postnatal day 7 (PD7). We measured local cerebral metabolic rates for glucose (LCMRglc) by the quantitative autoradiographic [14C]2‐deoxyglucose technique at pre‐ (PD21) and postpubertal (PD42) ages when NVHL rats do not express abnormal dopamine related behaviors, and at adulthood (PD70). We observed a widespread increase in LCMRglcs in PD21 NVHL indicative of an ongoing intense reorganization of the brain while at PD42, increases were less extended. At PD70, changes in glucose metabolism were restricted to specific systems, such as the auditory system, the cerebellum, the serotonergic median raphe, and median septum. These data show in a heuristic animal model of schizophrenia that functional metabolic changes within the brain could precede the onset of dopamine‐related behavioral alterations and lead to a distinct ensemble of functional changes in adulthood in systems that may be relevant to schizophrenia. © 2009 Wiley‐Liss, Inc.
Tubulin targets in the pathobiology and therapy of glioblastoma multiforme. I. class III β‐tubulin
Authors: Katsetos Christos D. , Dráberová Eduarda , Legido Agustin , Dumontet Charles , Dráber Pavel
Published: July 2009

Glioblastoma multiforme (GBM) is the most common and deadliest form of primary brain cancer in adults. Despite advances in molecular biology and genetics of gliomas currently there is no effective treatment or promising molecularly targeted experimental therapeutic strategies for these tumors. In previous studies we have shown aberrant overexpression of the class III β‐tubulin isotype (βIII‐tubulin) in GBM and have proposed that this change may reflect perturbations in microtubule dynamics associated with glioma tumorigenesis, tumor progression and malignant transformation into GBM. This minireview focuses on microtubules and tubulin as emerging targets in potential therapy of GBM using a new class of βIII‐tubulin‐targeted drugs in the light of recent developments concerning the function and potential role of this isotype in clinically aggressive tumor behavior, cancer stem cells, tumor hypoxia and chemoresistance to tubulin binding agents, principally taxanes. J. Cell. Physiol. 221: 505–513, 2009. © 2009 Wiley‐Liss, Inc.
Galactosyl derivative of Nω‐nitro‐L‐arginine: Study of antiproliferative activity on human thyroid follicular carcinoma cells
Authors: Melisi Daniela , Rosso Francesco , Curcio Annalisa , Tortora Carla , Nieddu Maria , Marino Gerardo , Lettieri Maria , Grimaldi Anna , Luongo Elvira , Romano Simona , Romano Maria Fiammetta , Boatto Gianpiero , Abignente Enrico , Barbarisi Alfonso , Rimoli Maria Grazia
Published: July 2009

The methyl ester prodrug of Nω‐nitro‐L‐arginine (L‐NAME) has been reported to exert anticancer effects against several human tumors, including thyroid carcinoma, by inhibiting nitric oxide synthase (NOS). However, chronic administration of L‐NAME has often led to adverse events causing cardiovascular alterations due to its potential toxic effect. Here we report for the first time the synthesis of the galactosyl ester prodrug of Nω‐nitro‐L‐arginine, NAGAL, a prodrug capable of inhibiting NOS more efficiently and with fewer adverse events than its parent drug. For this purpose RO82‐W‐1, a thyroid cell line derived from human follicular carcinoma, was used. MTT test results showed that NAGAL affected cell viability to a significantly greater extent than did L‐NAME. Moreover, fluorescence activated cell sorter (FACS) analyses revealed that NAGAL, compared to L‐NAME, was able to reduce nitric oxide (NO) production as well as increase the percentage of apoptotic thyreocytes. Western blot further confirmed the reduction in NOS‐II expression by NAGAL. Finally, by using the LC–MS technique, we found that NAGAL elicited a higher increase in Nω‐nitro‐L‐arginine (NA) concentration than did L‐NAME. Thus, this study suggests that NAGAL could be considered a potential therapeutic tool for those pathologies involving an overproduction of NO, including thyroid carcinoma. J. Cell. Physiol. 221: 440–447, 2009. © 2009 Wiley‐Liss, Inc.
Nano‐scale analysis of graphene layers by tip‐enhanced near‐field Raman spectroscopy
Authors: Saito Yuika , Verma Prabhat , Masui Kyoko , Inouye Yasushi , Kawata Satoshi
Published: July 2009

We demonstrate nano‐scale optical analysis of graphene layers by tip‐enhanced near‐field Raman spectroscopy (TERS). In this technique, the spatial resolution ∼30 nm is realized by the near‐field probe which acts as a nano‐light source. From the intensity change of the Raman band of silicon generated from the near‐field probe, we can conveniently estimate the edge boundaries and the number of stacking layers. TERS measurement across the layer edges reveals the nano‐scale properties of the material as well as the existence of local defects and edge boundaries. The intensity change of the G‐band shows the step‐like behavior that follows the layer boundary, whereas the two components in 2D peak show more complex behaviors even inside layers. The peak fluctuation in the 2D band also suggests the local stress distribution due to interlayer interactions. An excess charge effect is observed through the correlation between the peak position and the width of the G‐band and their nano‐scale distribution within a layer is revealed. Besides the vibrational analysis, we successfully performed the estimation of the number of layers in two‐dimensional imaging by the same experimental platform, which allows us high‐throughput nondestructive identification of graphene layers critical for the evaluation of this material especially in future device applications. Copyright © 2009 John Wiley & Sons, Ltd.
Temperature‐dependent Raman scattering in ferroelectric Bi4−xNdxTi3O12(x = 0, 0.5, 0.85) single crystals
Authors: Liang Kun , Qi Yajun , Lu Chaojing
Published: July 2009

The temperature‐dependent Raman spectra of ferroelectric Bi4−xNdxTi3O12(x = 0, 0.5, 0.85) single crystals were recorded from 100 to 800 K. It was found that there is a critical Nd content x0 between 0.5 and 0.85. The Nd3+ ions prefer to replace Bi3+ ions in pseudo‐perovskite layers when x < x0, while they might begin to incorporate into (Bi2O2)2+ layers when x ≥ x0. Nd substitution leads to a decrease in the ferroelectric–paraelectric transition temperature (Tc). A monoclinic distortion of orthorhombic structure occurs in Bi4Ti3O12 crystals at temperatures below 200 K. Copyright © 2009 John Wiley & Sons, Ltd.
Endoscopic management of Zenker's diverticulum: Stapler assisted versus Harmonic Ace
Authors: Sharp Dawn B. , Newman John R. , Magnuson J. Scott
Published: July 2009

Objectives/Hypothesis:

Endoscopic repair has become the preferred method of treatment for Zenker's diverticuli. The objective of this study is to compare the endoscopic stapling technique with a novel technique using the Harmonic Ace device (Ethicon Endo‐Surgery, Inc., Cincinnati, OH).

Study Design:

A retrospective chart review.

Methods:

Medical records of 48 consecutive patients who underwent endoscopic repair of a Zenker's diverticulum were reviewed. Data were gathered for demographics, symptoms, treatment techniques, and outcomes. Analysis was made using standard statistical methods.

Results:

A total of 52 endoscopic procedures were attempted and 50 performed: 28 stapler assisted, 20 Harmonic Ace assisted, and 2 using both techniques. Three procedures were aborted due to anatomic limitations. Forty‐four (88%) patients reported complete resolution of their symptoms. Overall, there were six (12%) reported complications. Five (17.9%) complications involved the stapler technique and 1 (5%) using the Harmonic Ace. The difference between these two groups was not significant (P < .38). The average diverticulum size was smaller in the Harmonic Ace group compared to the stapler group (P < .0017). Patients with diverticuli larger than 2 cm were more likely to have postoperative complications than those with smaller ones.

Conclusions:

Stapler and Harmonic Ace assisted endoscopic repair of Zenker's diverticulum are two safe and effective minimally invasive techniques. Postoperative complications are more likely due to size of the diverticulum and not the device used. The Harmonic Ace used alone or in combination with the stapler may offer additional advantages over conventional open and stapler assisted techniques, addressing size limitations and persistent symptoms. Laryngoscope, 2009
Human papillomavirus reduces the prognostic value of nodal involvement in tonsillar squamous cell carcinomas
Authors: Straetmans Jos M. J. A. A. , Olthof Nadine , Mooren Jeroen J. , de Jong Jos , Speel Ernst‐Jan M. , Kremer Bernd
Published: July 2009

Objectives/Hypothesis:

Assessment of the prognostic value of nodal status in relation to human papillomavirus (HPV) status and the various treatment modalities in tonsillar squamous cell carcinomas (TSCC).

Study Design:

Retrospective 5‐year survival analysis.

Methods:

A 5‐year follow‐up of disease‐free, disease‐specific, and overall survival in a group of 81 patients with TSCC was conducted. The nodal status and integration of HPV‐DNA in the genome (detected with fluorescence in situ hybridization) as prognostic indicators were examined while correcting for other clinical parameters (smoking habits, alcohol consumption, treatment modality, differentiation, TNM classification).

Results:

Of TSCCs, 41% were positive for HPV type 16. In these TSCCs, the primary tumor was significantly smaller when compared to HVP‐negative TSCCs (P = .04), whereas the percentage of cases with cervical metastases was identical. In the total population, it was not nodal involvement, but rather HPV manifestation, which was related to patient prognosis. Within the treatment modalities (surgery combined with radiotherapy and radiotherapy alone), neither nodal status nor HPV were prognostic indicators.

Conclusions:

Since a substantial percentage of TSCCs are HPV‐positive and metastasizes to cervical lymph nodes in less advanced primary tumors, the N status is an unreliable prognostic indicator in TSCCs. HPV is only prognostically relevant in the total tumor population, but loses its value within patient groups receiving a single treatment modality. The value of HPV for prognosis of patients with TSCC requires further study. Laryngoscope, 2009
Outcomes of tonsillectomy in neurologically impaired children
Authors: Conley Stephen F. , Beecher Robert B. , Delaney Amy L. , Norins Nan A. , Simpson Pippa M. , Li Shun‐Hwa
Published: July 2009

Objectives/Hypothesis:

Children with neurologically impaired (NI) swallow can undergo tonsillectomy safely and effectively.

Study Design:

Retrospective review.

Methods:

Forty‐five children with documented dysphagia were compared to age‐ and procedure‐matched normal children for operating room and clinical experience. Three further studies were limited to the NI children only: preoperative and postoperative video swallow studies (VSS), and polysomnography (PSG) for sleep‐disordered breathing history. Long‐term telephone follow‐up of clinical outcomes was performed.

Results:

There were no differences between the two groups measured by tonsil size or intraoperative or late post‐tonsillectomy hemorrhage, but lowest measured oxygen levels were statistically different. No intraoperative complications, early post‐tonsillectomy hemorrhage, hospital readmission, or mortality occurred in either group. Three NI children each had an episode of aspiration pneumonia (early or late) without sequelae. Of the 32 VSS available for review, postoperative aspiration incidence was significantly improved, but with new‐onset aspiration occurring in five children. Of available matched pre‐ and postoperative PSG, 91% confirmed resolution of identified preoperative obstructive sleep apnea. Long‐term telephone follow‐up of 20 NI children revealed improved breathing (95%), communication (90%), and feeding efficiency (55%).

Conclusions:

This study suggests tonsillectomy in NI children can be performed safely with appropriate monitoring and precautions with a 48‐hour hospital postoperative stay recommended. Swallowing safety appears to improve both objectively and subjectively in most NI children following tonsillectomy. Both preoperative and postoperative VSS are recommended for any NI child undergoing tonsillectomy. Long‐term follow‐up identified improved quality of life measures for the majority of the NI children queried. Laryngoscope, 2009
Propranolol for airway hemangiomas: Case report of novel treatment
Authors: Buckmiller Lisa , Dyamenahalli Umesh , Richter Gresham T.
Published: July 2009

Infantile hemangiomas arising in the trachea are rare. These lesions pose a management dilemma as several treatment options can provide safe management. Propranolol, a nonselective beta‐blocker, has recently been introduced as a novel modality for the treatment of proliferating hemangiomas. This report illustrates the successful management of tracheal hemangiomas using oral propranolol in a young patient with otherwise treatment‐resistant airway lesions. Despite various endoscopic therapeutic attempts, the patient remained stridulous with airway disease that persisted into the involution phase of the average hemangioma cycle. Within 6 weeks of beginning oral propranolol (2 mg/kg/day), her airway compromise was eliminated and she had complete resolution of endoscopically visible disease. No side effects from propranolol occurred. We propose that oral propranolol should be considered for use in airway hemangiomas. Laryngoscope, 2009
Differential mRNA expression in in vivo produced pre‐implantation embryos of dairy heifers and mature cows
Authors: Pretheeban T. , Gordon M. , Singh R. , Perera R. , Rajamahendran R.
Published: July 2009

Decreasing fertility with increasing parity is considered to be a major constraint in the reproductive management of dairy cows. Even though pregnancy rates (PR) in mature cows have declined drastically in the last 50 years, it has remained constant in heifers. Early embryonic loss is a major cause for the loss of pregnancy in cows. Expression of developmentally important genes is vital for the function and survival of embryos. Hence, in this study, we compared the mRNA abundance of GLUT5, INFτ, HSP70, Na/K‐ATPase, BAX, and BCL2 genes in the pre‐implantation embryos of dairy heifers and mature cows. Heifers (n = 25) and cows (n = 20) were superovulated and artificially inseminated on the day of estrus. On day 7, the embryos were flushed and morphologically graded and RT‐PCR was performed. HSP70 was expressed more in the grade I embryos in heifers than in cows, and in the grade I embryos of heifers than in grade II embryos of heifers. In pooled embryos (both grades I and II) of heifers and cows, expression for INFτ was greater in heifers than in cows. Grade I embryos had a higher expression of GLUT5 and Na/K‐ATPase than the grade II embryos of cows. From this study, we conclude that there is differential expression of some developmentally important genes between embryos of heifers versus cows and between grades I and II embryos regardless of the embryo source. Future research will be necessary to elucidate any potential cause and effect between these genes and reduced PR observed in dairy cows. Mol. Reprod. Dev. 76: 1165–1172, 2009. © 2009 Wiley‐Liss, Inc.
Diffusion tensor imaging detects axonal injury and demyelination in the spinal cord and cranial nerves of a murine model of globoid cell leukodystrophy
Authors: Hofling A. Alex , Kim Joong Hee , Fantz Corinne R. , Sands Mark S. , Song Sheng‐Kwei
Published: July 2009

Globoid cell leukodystrophy is an inherited neurodegenerative disorder caused by a deficiency of the lysosomal enzyme galactosylceramidase. In both human patients and the authentic murine Twitcher model, pathological findings include demyelination as well as axonal damage in both the central and peripheral nervous system. Diffusion tensor imaging (DTI) has emerged as a powerful noninvasive technique that is sensitive to these white matter disease processes. Increases in radial diffusivity (λ⟂) and decreases in axial diffusivity (λ∥) correlate with histopathological evidence of demyelination and axonal damage, respectively. Compared to age‐matched, normal littermates, DTI of optic nerve and trigeminal nerve in end‐stage Twitcher mice displayed a statistically significant increase in λ⟂ and decrease in λ∥, consistent with previously characterized demyelination and axonal damage in these regions. In the Twitcher spinal cord, a statistically significant decrease in λ∥ was identified in both the dorsal and ventrolateral white matter, relative to normal controls. These results were consistent with immunofluorescence evidence of axonal damage in these areas as detected by staining for nonphosphorylated neurofilaments (SMI32). Increase in λ⟂ in Twitcher spinal cord white matter relative to normal controls reached statistical significance in the dorsal columns and approached statistical significance in the ventrolateral region. Correlative reduced levels of myelin basic protein were detected by immunofluorescent staining in both these white matter regions in the Twitcher spinal cord. Fractional anisotropy, a nonspecific but sensitive indicator of white matter disease, was significantly reduced in the optic nerve, trigeminal nerve, and throughout the spinal cord white matter of Twitcher mice, relative to normal controls. This first reported application of spinal cord DTI in the setting of GLD holds potential as a noninvasive, quantitative assay of therapeutic efficacy in future treatment studies. Copyright © 2009 John Wiley & Sons, Ltd.
Constrained decompositions of integer matrices and their applications to intensity modulated radiation therapy
Authors: Engelbeen Céline , Fiorini Samuel
Published: July 2009

We consider combinatorial optimization problems arising in radiation therapy. Given a matrix I with non‐negative integer entries, we seek a decomposition of I as a weighted sum of binary matrices having the consecutive ones property, such that the total sum of the coefficients is minimized. The coefficients are restricted to be non‐negative integers. Here, we investigate variants of the problem with additional constraints on the matrices used in the decomposition. Constraints appearing in the application include the interleaf motion and interleaf distance constraints. The former constraint was previously studied by Baatar et al. [Discr Appl Math 152 (2005), 6–34] and Kalinowski [Discr Appl Math 152 (2005), 52–88]. The latter constraint was independently considered by Kumar [Working paper (2007)] in the case where coefficients of the decomposition are not restricted to be integers. For both constraints, we prove that finding an optimal decomposition reduces to finding a maximum value potential in an auxiliary network with integer arc lengths and no negative length cycle. This allows us to simplify and unify the previous approaches. Moreover, we give an O (MN + KM) algorithm to solve the problem under the interleaf distance constraint, where M and N, respectively, denote the number of rows and columns of the matrix I and K is the number of matrices used in the decomposition. We also give an O (MN log M + KM) algorithm for solving the problem under the interleaf motion constraint and hence improve on previous results. Finally, we show the problem can still be solved in O (MN log M + KM) time when both constraints are considered simultaneously. © 2009 Wiley Periodicals, Inc. NETWORKS, 2010
Simple and efficient integration of rigid rotations suitable for constraint solvers
Authors: Koziara Tomasz , Bićanić Nenad
Published: July 2009

Simple and efficient way of integrating rigid rotations is presented. The algorithm is stable, second‐order accurate, and in its explicit version involves evaluation of only two exponential maps per time step. The semi‐explicit version of the proposed scheme improves upon the long‐term stability, while it retains the explicitness in the force evaluation. The algebraic structure of both schemes makes them suitable forthe analysis of constrained multi‐body systems. The explicit algorithm is specifically aimed at the analysis involving small incremental rotations, where its modest computational cost becomes the major advantage. The semi‐explicit scheme naturally broadens the scope of possible applications. Copyright © 2009 John Wiley & Sons, Ltd.
Symptom clusters of heart failure
Authors: Jurgens Corrine Y. , Moser Debra K. , Armola Rochelle , Carlson Beverly , Sethares Kristen , Riegel Barbara
Published: July 2009

Patients with heart failure (HF) report multiple symptoms. Change in symptoms is an indicator of HF decompensation. Patients have difficulty differentiating HF symptoms from comorbid illness or aging. The study purpose was to identify the number, type, and combination of symptoms in hospitalized HF patients and test relationships with comorbid illness and age. A secondary analysis from a HF registry (N = 687) was conducted. The sample was 51.7% female, mean age 71 ± 12.5 years. The theory of unpleasant symptoms informed the study regarding the multidimensional nature of symptoms. Factor analysis of nine items from the Minnesota Living with HF Questionnaire resulted in three factors, acute and chronic volume overload and emotional distress. Clusters occurred more frequently in older patients, but caused less impact. © 2009 Wiley Periodicals, Inc. Res Nurs Health 32:551–560, 2009
A microarray‐based approach for the identification of epigenetic biomarkers for the noninvasive diagnosis of fetal disease
Authors: Chu Tianjiao , Burke Brian , Bunce Kimberly , Surti Urvashi , Allen Hogge W. , Peters David G.
Published: July 2009

Objectives

We describe a novel microarray‐based approach for the high‐throughput discovery of epigenetic biomarkers for use in the noninvasive detection of fetal genetic disease.

Methods

We combined a 215 060‐probe custom oligonucleotide microarray with a comprehensive library preparation method and novel statistical tools to compare DNA methylation patterns in chorionic villus samples (CVS) with gestational age‐matched maternal blood cell (MBC) samples. Our custom microarray was designed to provide high‐resolution coverage across human chromosomes 13, 18 and 21.

Results

We identified 6311 MspI/HpaII sites across all three chromosomes that displayed tissue‐specific differential CpG methylation patterns. To maximize the probability of identifying biomarkers that have clinical utility we filtered our data to identify MspI/HpaII sites that are within 150 bp of a highly polymorphic single nucleotide polymorphism (SNP) so that its allelic ratio may be determined for the detection of fetal aneuploidy. Our microarray design and the computational tools used for data analysis are available for download as is the entire data set.

Conclusions

This high‐resolution analysis of DNA methylation patterns in the human placenta during the first trimester of pregnancy identifies numerous potential biomarkers for the diagnosis of fetal aneuploidy on chromosomes 13, 18 and 21. Copyright © 2009 John Wiley & Sons, Ltd.
An exploration of anticipatory grief in advanced cancer patients
Authors: Cheng Joanna O. Y. , Lo Raymond S. K. , Chan Faye M. Y. , Kwan Bonnie H. F. , Woo Jean
Published: July 2009

Background and objectives: Research on anticipatory grief (AG) has been more focused on the experience of relatives than the terminally ill patients. This study will present qualitative ‘thick descriptions’ of advanced cancer patient's experience of AG and explore how it is experienced in the family context.

Method: Seven advanced incurable cancer patients (median 58 years) were recruited from the day hospice and five patients comprised the final sample. Participants were invited to attend focus groups and individual interviews to discuss their experience of terminal illness, thoughts and feelings related to AG and how they cope with losses and grief in the family. Qualitative transcripts were analyzed using interpretative phenomenological analysis.

Result: Two inter‐related themes of AG were identified. The first main theme ‘subjective experience of AG’ comprises confrontations with death and multiple losses; and resistance against death and loss. The second main theme ‘experience of AG in the family’ explored the patient's role in the family interaction patterns and interpersonal processes.

Conclusion: An understanding in the subjective experience of AG in terminally ill patients and their experience of AG in the family may contribute to the development of psychotherapeutic interventions. The generative role of the patient in the family grief process is also highlighted.Copyright © 2009 John Wiley & Sons, Ltd.
Addressing model uncertainty in seasonal and annual dynamical ensemble forecasts
Authors: Doblas‐Reyes F. J. , Weisheimer A. , Déqué M. , Keenlyside N. , McVean M. , Murphy J. M. , Rogel P. , Smith D. , Palmer T. N.
Published: July 2009

The relative merits of three forecast systems addressing the impact of model uncertainty on seasonal/annual forecasts are described. One system consists of a multi‐model, whereas two other systems sample uncertainties by perturbing the parametrization of reference models through perturbed parameter and stochastic physics techniques. Ensemble re‐forecasts over 1991 to 2001 were performed with coupled climate models started from realistic initial conditions. Forecast quality varies due to the different strategies for sampling uncertainties, but also to differences in initialisation methods and in the reference forecast system. Both the stochastic‐physics and perturbed‐parameter ensembles improve the reliability with respect to their reference forecast systems, but not the discrimination ability. Although the multi‐model experiment has an ensemble size larger than the other two experiments, most of the assessment was done using equally‐sized ensembles. The three ensembles show similar levels of skill: significant differences in performance typically range between 5 and 20%. However, a nine‐member multi‐model shows better results for seasonal predictions with lead times shorter than five months, followed by the stochastic‐physics and perturbed‐parameter ensembles. Conversely, for seasonal predictions with lead times longer than four months, the perturbed‐parameter ensemble gives more often better results. All systems suggest that spread cannot be considered a useful predictor of skill. Annual‐mean predictions showed lower forecast quality than seasonal predictions. Only small differences between the systems were found. The full multi‐model ensemble has improved quality with respect to all other systems, mainly from the larger ensemble size for lead times longer than four months and annual predictions. Copyright © 2009 Royal Meteorological Society and Crown Copyright