bluuebunny/crossref_metadata_2025 huggingface dataset:
Accurate determination of polyethylene pellet density using transmission Raman spectroscopy
Authors: Kim Mooeung , Chung Hoeil , Jung Young Mee
Published: June 2011

In this study, transmission Raman spectroscopy was explored for the direct measurement of the density of packed polyethylene (PE) pellets. A simple and direct transmission Raman measurement of packed, solid granules or pellet samples without pretreatment is greatly advantageous. Initially, the optimal packing thickness of PE pellets for transmission Raman measurement was determined by investigating the reproducibility of triplicate spectra collected by varying the thickness from 2 to 9 cm. Once determined, transmission Raman spectra were collected for 25 different grades of PE pellets and the partial least squares method was used to determine the sample density. The resulting accuracy was 0.00067 g·cm−3, while that obtained using backscattering measurements was 0.00083 g·cm−3. To investigate possible inhomogeneity within a pellet, Raman line mapping was performed over the face of a sectioned pellet and spectral variations among the mapped spectra were examined using principal component analysis. In addition, differential scanning calorimetry was performed on three samples prepared separately by cutting a pellet into left, middle, and right sections. Based on both studies, internal pellet inhomogeneity was found to be minute, but was clearly present. The correct sample representation of internally inhomogeneous PE pellets by the transmission Raman measurement eventually improved the accuracy for density determination. Finally sample‐to‐sample two‐dimensional correlation analysis was used to further examine the origin of the improved accuracy. Copyright © 2011 John Wiley & Sons, Ltd.
Structural modifications of LixV2O5 in a composite cathode (0≤x < 2) investigated by Raman microspectrometry
Authors: Baddour‐Hadjean R. , Marzouk A. , Pereira‐Ramos J. P.
Published: June 2011

The structural behaviour of the LixV2O5 active material in a composite electrode is determined upon lithium insertion/extraction in the 4–2.15 V potential range (0≤x < 2) using Raman microspectrometry. For the first time, a detailed description of phase transitions occurring in the V2O5 composite electrode is provided by Raman spectroscopy, on the basis of a complete assignment of the spectra. This approach has been successful because of the knowledge of the Raman fingerprints of the chemically lithiated compounds, combined with a rigorous and systematic deconvolution of the Raman spectra obtained for the electrochemically lithiated materials. The successive emergence of α, ε, δ and γ phases is clearly established, as well as the α/ε, ε/δ and δ/γ biphasic regions corresponding to the 3.4, 3.2 and 2.3 V potential plateaus, respectively. This study shows that Raman spectroscopy constitutes a sensitive and relevant tool to explore the emergence of the various phases governing the electrochemical properties of cathode materials for lithium batteries. Copyright © 2011 John Wiley & Sons, Ltd.
Structure and conformation of Arg8 vasopressin modified analogs
Authors: Podstawka‐Proniewicz Edyta , Sobolewski Dariusz , Prahl Adam , Kim Younkyoo , Proniewicz Leonard M.
Published: June 2011

Fourier‐transform Raman and infrared spectra were acquired for four arginine vasopressin (AVP) analogs containing L‐diphenylalanine (Dpa): [Dpa2]AVP, [Cpa1,Dpa2]AVP, [Dpa3]AVP, and [Cpa1,Dpa3]AVP (where Cpa denotes 1‐mercaptocyclohexaneacetic acid). We compared and analyzed these spectra. In addition, the Raman spectra were compared to the corresponding surface‐enhanced Raman scattering spectra recorded in an aqueous silver colloidal dispersion. Silver colloidal dispersions prepared by the simple borohydride reduction of silver nitrate were used as substrates. The geometry of these molecules etched on the silver surface was deduced from the observed changes in the intensity enhancement, breadth, and shift in wavenumber of the Raman bands in the spectra of the bound versus free species. Based on the obtained data, adsorption mechanisms were proposed for each case, and the suggested adsorbate structures were compared. All the molecules were thought to adsorb onto a silver surface via a phenyl ring, free electron pairs on the sulfur atom, and CO and CONH‐bonds. However, the orientation of these fragments on the colloidal silver surface and the strength of the interactions with this surface are different. For [Dpa3]AVP and [Cpa1,Dpa3]AVP, a strong interaction among the—CCN‐peptide fragment and the colloidal silver surface occurs. Copyright © 2011 John Wiley & Sons, Ltd.
Local structural order in carbonic acid polymorphs: Raman and FT‐IR spectroscopy
Authors: Mitterdorfer Christian , Bernard Jürgen , Klauser Frederik , Winkel Katrin , Kohl Ingrid , Liedl Klaus R. , Grothe Hinrich , Mayer Erwin , Loerting Thomas
Published: June 2011

Two different polymorphs of carbonic acid, α‐ and β‐H2CO3, were identified and characterized using infrared spectroscopy (FT‐IR) previously. Our attempts to determine the crystal structures of these two polymorphs using powder and thin‐film X‐ray diffraction techniques have failed so far. Here, we report the Raman spectrum of the α‐polymorph, compare it with its FT‐IR spectrum and present band assignments in line with our work on the β‐polymorph [Angew. Chem. Int. Ed. 48 (2009) 2690–2694]. The Raman spectra also contain information in the wavenumber range ∼90–400 cm−1, which was not accessible by FT‐IR spectroscopy in the previous work. While the α‐polymorph shows Raman and IR bands at similar positions over the whole accessible range, the rule of mutual exclusion is obeyed for the β‐polymorph. This suggests that there is a center of inversion in the basic building block of β‐H2CO3 whereas there is none in α‐H2CO3. Thus, as the basic motif in the crystal structure we suggest the cyclic carbonic acid dimer containing a center of inversion in case of β‐H2CO3 and a catemer chain or a sheet‐like structure based on carbonic acid dimers not containing a center of inversion in case of α‐H2CO3. This hypothesis is strengthened when comparing Raman active lattice modes at < 400 cm−1 with the calculated Raman spectra for different dimers. In particular, the intense band at 192 cm−1 in β‐H2CO3 can be explained by the inter‐dimer stretching mode of the centrosymmetric RC(OHO)2 CR entity with ROH. The same entity can be found in gas‐phase formic acid (RH) and in β‐oxalic acid (RCOOH) and produces an intense Raman active band at a very similar wavenumber. The absence of this band in α‐H2CO3 confirms that the difference to β‐H2CO3 is found in the local coordination environment and/or monomer conformation rather than on the long range. Copyright © 2011 John Wiley & Sons, Ltd.
Raman spectroscopy to probe residual stress in ZnO nanowire
Authors: Sahoo Satyaprakash , Sharma G. L. , Katiyar Ram. S.
Published: June 2011

Raman spectroscopic studies are performed to probe the stress along the length of a bent ZnO nanowire. The zone‐centre E2high optical phonon shows a systematic red shift as the junction point of the two arms of the nanowire is approached. The mechanism of the red shift is discussed on the basis of the tensile strain. From the red shift of the phonon peak position, the strain at different regions on the nanowire is estimated. Stress in the bent nanowire is also investigated using photoluminescence (PL) spectroscopy. Results of both Raman and PL study confirm that the bent nanowire is under tensile strain. Copyright © 2011 John Wiley & Sons, Ltd.
Micro‐Raman study of orbiton–phonon coupling in YbVO3
Authors: Roberge B. , Jandl S. , Nugroho A. A. , Palstra T. T. M.
Published: June 2011

First‐order and multiphonon Raman active excitations are studied in YbVO3 as a function of temperature in the orthorhombic and monoclinic phases. Below T ≃ 170 K, a G‐type orbital ordering with a concomitant monoclinic transition occurs. They enhance the phonon polarizabilities, allowing the resolution of room‐temperature bands, and activate new excitations around 700 cm−1. Below T ∼ 65 K, the 700 cm−1 excitations disappear, indicating a C‐type orbital ordering and a return to the orthorhombic structure. The observed phonon combinations around 1400 cm−1 with a dominant Jahn‐Teller vibration at ∼690 cm−1 reflect a possible orbiton‐phonon coupling. Copyright © 2011 John Wiley & Sons, Ltd.
Whey protein–polysaccharide blended edible film formation and barrier, tensile, thermal and transparency properties
Authors: Yoo SeungRan , Krochta John M
Published: June 2011

BACKGROUND: Films made from different protein (P) or polysaccharide (PS) materials have widely different properties. The objective of this study was to determine whether whey protein isolate (WPI)‐PS blended films possess a combination of properties intermediate and possibly superior to WPI or PS film alone.

RESULTS: Oxygen permeability (OP) and tensile strength (TS) for PS‐WPI blended films were intermediate between the OP and TS properties of pure methycellulose (MC), hydroxypropylmethylcellulose (HPMC) or sodium alginate (SA) film and pure WPI film. Starch‐WPI blends gave the weakest films. Water vapor permeability values for all pure and blended films were similar. Blended films made of MC, HPMC or SA with WPI had lower transparency than pure MC, HPMC, SA or WPI films. Differential scanning calorimetry thermograms obtained from the blended films exhibited a single glass transition temperature (Tg) at an intermediate value between the Tg values of the pure films.

CONCLUSIONS: Whether properties of PS‐WPI blended films are intermediate to properties of the pure PS and WPI film depends on the particular PS and specific property. In the case of MC or HPMC with WPI, the blended films reflect the higher TS of the PS and lower OP of the WPI. Copyright © 2011 Society of Chemical Industry
Monitoring of barley starch amylolysis by gravitational field flow fractionation and MALDI‐TOF MS
Authors: Mazanec Karel , Dycka Filip , Bobalova Janette
Published: June 2011

BACKGROUND:In barley, starch occurs in the form of granules with bimodal size distribution. Enzymatic hydrolysis of the starch granule is one of the most important reactions occurring during malting and mashing. Previous studies revealed the discrepancies in the assumption that barley varieties with better malting qualities should have a higher A/B (large/small starch granules) ratio. This led us to focus our attention on detailed analysis of two barley varieties, Jersey and Tolar, both with high malting quality but significantly differing in A/B (1.28 and 0.66, respectively), were chosen for more detailed analysis in the actual work. In this study, the capacity of gravitational field flow fractionation (GFFF) to monitor amylolysis of the starch granules was investigated.

RESULTS:Isolated starch granules from these two barley cultivars were treated with amylases. The changes in starch granule size and bimodal distribution were studied by GFFF. Simultaneously, free sugars released during enzymatic digestion were observed by matrix‐assisted laser desorption ionization time‐of‐flight mass spectrometry. The changes in the fractogram and in the mass spectra reflect a correlation with the progress of enzymatic hydrolysis.

CONCLUSION:The results show the interest in utilization of GFFF as a simple and cheap method for monitoring changes in the distribution of the starch granule size during amylolysis. Copyright © 2011 Society of Chemical Industry
Results of isolated lower limb perfusion for loco‐regional advanced/recurrent melanoma using borderline true hyperthermia plus additional bolus of melphalan. A critical analysis of homogeneous cases
Authors: Pace Marcello , Gattai Riccardo , Mascitelli Erminia M. , Millanta Luigi
Published: June 2011

Background and Objective

This study was conducted to assess the safety and efficacy of our modified ILP treatment with borderline true hyperthermia and high melphalan concentration in stage III lower limb melanoma.

Methods

Between March 1990 and December 2006, 91 consecutive patients were given ILP treatment. Forty three patients were treated with double L‐PAM bolus combined with D‐actinomicin; 48 patients were treated with additional L‐PAM bolus alone.

Results

The mean follow‐up period is 68.5 months. The acute regional toxicity occurred with grade II (54%), III (38%), IV (2.1%). The systemic toxic effects were present with transitory hematological disorders. Complete response (CR) rate was observed in 89.2% of stage IIIA‐IIIAB unexcised IT‐mets. The overall limb recurrent disease in stage III was 39%. In patients with CR recurrent rate occurred in 44% with a mean limb recurrence‐free interval (LRFI) of 23.8 months. Distant metastases was attained with a mean time of 29.2 months. After CR, the interval was 32.1 months. The 5‐year survival rate was 45%; in patients with CR, was 48%.

Conclusions

Our procedure is an important therapeutic option. The results suggest a marked local control of the recurrent disease. The LRFI is longer than for those treated with other treatment schedules. J. Surg. Oncol. 2011; 104:718–723. © 2011 Wiley Periodicals, Inc.
Separation of polyphenols using porous polyamide resin and assessment of mechanism of retention
Authors: Gao Min , Wang Xiaolei , Gu Ming , Su Zhiguo , Wang Ye , Janson Jan‐Christer
Published: June 2011

A porous polyamide resin is shown to possess hydrogen bond acceptor properties suitable for the separation of polyphenolic solutes such as phenolic acids, flavonols and flavonoids. The separation is achieved in the presence of solvent mixtures of acetic acid and ethanol. The extent of hydrogen bond adsorption is reviewed based on data obtained from the elution behaviour of a variety of simple polyphenolic solutes. Polyamide adsorption chromatography was applied for the purification of resveratrol and polydatin from Polygonum cuspidatum Sieb. & Zucc.
Silica‐based and organic monolithic capillary columns for LC: Recent trends in proteomics
Authors: Rozenbrand Johan , van Bennekom Wouter P.
Published: June 2011

The use of monolithic liquid chromatography (LC) columns for proteomics, covering the scientific literature from 2004 to the beginning of 2011, is reviewed. Attention is paid to recent developments in column technology and materials, focusing on silica‐based and organic (polystyrene and methacrylate) monolithic capillary columns for proteomics. The applicability of these columns is illustrated by examples of the analysis of (complex) protein digests and proteins conveniently summarized in tables. Furthermore, characteristics of column materials are compared and future trends and prospects are presented.
Narrow‐bore core–shell particles and monolithic columns in the analysis of silybin diastereoisomers
Authors: Marhol Petr , Gažák Radek , Bednář Petr , Křen Vladimír
Published: June 2011

Two chromatographic narrow‐bore columns, a novel 2.6 μm particle‐packed Kinetex™ C18 core–shell (50×2.1 mm id) and monolithic Chromolith® FastGradient RP‐18e (50×2 mm id), were evaluated for the analysis of diastereoisomers of the flavonolignans silybin and 23‐O‐acetylsilybin under isocratic conditions. The main advantages of the core–shell column are markedly higher efficiency (hmin=2.8 versus 5.6 for silybin A) and better peak symmetry. The Kinetex column exhibits only a slight change in the height equivalent of the theoretical plate with a higher linear velocity of the mobile phase. The monolithic column shows notably higher selectivity in terms of selectivity factor (1.21 versus 1.12) in the analysis of critical‐pair of diastereoisomers (silybin A and silybin B) and enables shorter run duration (approx. twofold) together with lower backpressure. The resolution power was found to be comparable, but the Kinetex column required a higher pressure of the mobile phase that, together with the higher chance of clogging, can be a disadvantage in the separation of biological samples. Successful baseline separation of silybin diastereoisomers in real pharmaceutical sample on monolithic column was accomplished.
Synthesis and Characterization of Well‐Defined Mid‐Chain Functional Macrophotoinitiators of Polystyrene by Combination of ATRP and “Click” Chemistry
Authors: Degirmenci Mustafa , Alter Selma , Genli Nasrettin
Published: June 2011

A combination of ATRP and “click” chemistry is employed for efficient preparation of a novel well‐defined mid‐chain functional macrophotoinitiator of polystyrene. Bromo‐terminated polystyrene (PSt‐Br) is prepared by ATRP of styrene using a methyl‐2‐bromopropanoate initiator with CuBr/PMDETA. Subsequently, PSt‐Br is converted to PSt‐N3 by a simple nucleophilic substitution reaction. A dialkyne‐functionalized photoinitiator (alkyne‐PI‐alkyne) is synthesized using a dihydroxy‐functional photoinitiator and propargyl bromide. Then the “click” reaction between PSt‐N3 and alkyne‐PI‐alkyne is performed by Cu(I) catalysis. Spectroscopic studies reveal that low‐polydispersity polystyrene with the desired photoinitiator functionality in the middle of the chain (PSt‐PI‐PSt) is obtained.

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Synthesis and Electrochemical Study of a Functional Ionic Polymer
Authors: Nagarale Rajaram K. , Bhattacharya Bhaskar , Jadhav Nitin A. , Singh Pramod K.
Published: June 2011

Viologen‐modified poly(vinylphosphonic acid) is synthesized by a simple EDC coupling reaction and characterized by FTIR and 1H NMR spectroscopy. Electrochemical studies of the polymer are performed in solution and on a skin‐printed electrode, the latter after making a composite with TEOS. A first redox peak is found at E0 = −0.57 V. The polymer is found to show diffusion‐confined phenomena in solution and surface‐confined phenomena on the electrode. On increasing the silica content, an increase in the resistivity of the film is found, which is reflected in an increase of the anodic‐to‐cathodic peak separation. From a plot of the current vs. the scan rate, the surface concentration of the redox‐active species is found to be 2.5 × 10−10 mol · cm2.

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Fundamental theorem of hyperbolic geometry without the injectivity assumption
Authors: Yao Guowu
Published: June 2011

Let \documentclass{article}\usepackage{amssymb,amsmath,amsthm,amscd,amsxtra}\begin{document}\pagestyle{empty}$\mathbb {H}^n$\end{document} be the n‐dimensional hyperbolic space. It is well‐known that, if \documentclass{article}\usepackage{amssymb,amsmath,amsthm,amscd,amsxtra}\begin{document}\pagestyle{empty}$f:\;\mathbb {H}^n\rightarrow \mathbb {H}^n$\end{document} is a bijection that preserves r‐dimensional hyperplanes, then f is an isometry. In this paper we make neither injectivity nor r‐hyperplane preserving assumptions on f and prove the following result:

Suppose that \documentclass{article}\usepackage{amssymb,amsmath,amsthm,amscd,amsxtra}\begin{document}\pagestyle{empty}$f:\;\mathbb {H}^n\rightarrow \mathbb {H}^n$\end{document} is a surjective map and maps an r‐hyperplane into an r‐hyperplane, then f is an isometry.

The Euclidean version was obtained by Chubarev and Pinelis in 1999 among other things. Our proof is essentially different from their and the similar problem arising in the spherical case is still open.
Well‐defined Biobased Segmented Polyureas Synthesis via a TBD‐catalyzed Isocyanate‐free Route
Authors: Tang Donglin , Mulder Dirk‐Jan , Noordover Bart A. J. , Koning Cor E.
Published: June 2011

Via an isocyanate‐free route, a series of segmented polyureas (PUs) were synthesized from (potentially) renewable resources. To the best of our knowledge, the present work shows for the first time that the organic superbase guanidine 1,5,7‐triazabicyclododecene (TBD) which was originally developed as a catalyst for the ring‐opening polymerization of lactones, lactides or cyclic carbonates, is also a promising catalyst for the transurethanization between dicarbamates and diamino‐terminated poly(propylene glycol) (PPGda) providing PUs via an isocyanate‐free strategy. The renewable segmented PUs contain monodisperse hard segments (HSs). This well‐defined structure was verified by the DMTA plots of the PUs, showing a sharp glass transition, a sharp flow transition and a flat rubbery plateau. The flow and maximum use temperature (Tfl) of the PUs increases with the increasing number of urea groups in the corresponding dicarbamates. In addition, at constant HS length, the length of the soft‐segment (SS) can be changed to adjust the properties of the PU materials, enabling their application as adhesives, soft elastomers, or rigid plastics.

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Diversified Applications of Chemically Modified 1,2‐Polybutadiene
Authors: Yuan Jiayin , ten Brummelhuis Niels , Junginger Mathias , Xie Zailai , Lu Yan , Taubert Andreas , Schlaad Helmut
Published: June 2011

Commercially available 1,2‐PB was transformed into a well‐defined reactive intermediate by quantitative bromination. The brominated polymer was used as a polyfunctional macroinitiator for the cationic ring‐opening polymerization of 2‐ethyl‐2‐oxazoline to yield a water‐soluble brush polymer. Nucleophilic substitution of bromide by 1‐methyl imidazole resulted in the formation of polyelectrolyte copolymers consisting of mixed units of imidazolium, bromo, and double bond. These copolymers, which were soluble in water without forming aggregates, were used as stabilizers in the heterophase polymerization of styrene and were also studied for their ionic conducting properties.

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Renewable Polyethylene Mimics Derived from Castor Oil
Authors: Türünç Oĝuz , Montero de Espinosa Lucas , Meier Michael A. R.
Published: June 2011

An increasing number of reports on the syntheses of carbohydrate‐ and plant oil‐based polymers has been published in ongoing efforts to produce plastic materials from renewable resources. Although many of these polymers are biodegradable and this is a desirable property for certain applications, in some cases non‐degradable polymers are needed for long‐term use purposes. Polyolefins are one of the most important classes of materials that have already taken their places in our daily life. On the other hand, their production relies on fossil resources. Therefore, within this contribution, we discuss synthetic routes toward a number of polyethylene mimics derived from fatty acids via thiol‐ene and ADMET polymerization reactions in order to establish more sustainable routes toward this important class of polymers. Two different diene monomers were thus prepared from castor oil derived platform chemicals, their polymerization via the two mentioned routes was optimized and compared to each other, and their thermal properties were investigated.

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Electronic Structure Calculations for Hole‐Transporting Triphenylamine Derivatives in Polymer Light‐Emitting Diodes
Authors: Kröner Dominik , Krüger Hartmut , Thesen Manuel W.
Published: June 2011

Hole‐transporting polymers based on polyethene‐triphenylamine derivatives are investigated with respect to their UV/Vis spectra. Two substituents, N‐phenyl‐1‐naphthylamine and carbazole, are examined as their respective polymer light‐emitting diodes (PLEDs) show very different luminous efficiencies. In order to identify the origin of these phenomena electronic structure calculations based on TD‐DFT were performed using monomer models of the hole‐transporting polymers. In experiment these hole‐transporting polymers show very specific differences in their absorption and emission (fluorescence and phosphorescence) spectra. The analysis of the simulated absorption and emission spectra, the MOs as well as the ground and excited state geometries give explanations for the different optical performances of the corresponding PLEDs.

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Diagnosis and treatment of complications related to deep brain stimulation hardware
Authors: Baizabal Carvallo José Fidel , Simpson Richard , Jankovic Joseph
Published: June 2011

Deep brain stimulation is a therapeutic technique increasingly used in the treatment of a variety of neurological, psychiatric, and pain disorders. Although beneficial, it carries the immediate and long‐term risks associated with implanted hardware in the brain parenchyma and subcutaneous tissue. The most common hardware complications include electrode migrations or misplacements, wire fractures, skin erosion, infections, and device malfunction. We systematically reviewed the literature on deep brain stimulation–related complications and propose a diagnostic and therapeutic algorithm. Our aim is to provide a guide for clinicians and medical staff involved in the treatment of patients with deep brain stimulation for rapid recognition and efficient management of these complications. © 2011 Movement Disorder Society
Rainfed wheat yields under climate change in northeastern Iran
Authors: Eyshi Rezaie E. , Bannayan Mohammad
Published: June 2011

Projecting agricultural crop, such as bread wheat, yield under future climate plays a vital role in planning for supply and demand, especially in developing countries. The objective of this study was to investigate impacts of climate change on grain yield of rainfed wheat in the Kashafrood basin situated in northeastern Iran. Climate projections of two General Circulation Models (HadCM3 and CGCM2) under two climate change scenarios (A2 and B2) were employed in this study. A statistical downscaling method was employed for developing the quantitative relationship between large‐scale atmospheric variables (predictors) and local variables (observations), also daily climatological parameters performed by the LARS‐WG5 stochastic weather generator, the Decision Support System for Agrotechnology Transfer (DSSAT) Version 4.5 adjusted to evaluate rainfed wheat performance. Results of this study represented substantial difference between GCM models and scenarios for wheat yield in the study area. The A2 scenario indicated more negative impact on wheat yield than the B2 using both GCM models. Highest increase and decrease of grain yield in comparison with the baseline belongs to the 2010–2039 period (+15%) using the HadCM3 model under the B2 scenario and the HadCM3 model under A2 in the 2040–2069 period (−50%), respectively. In general, growth period length indicated a markedly decreasing trend in both periods. There were strong relations between wheat yield and precipitation rate and growth period length in this study. Copyright © 2011 Royal Meteorological Society
Climate variability in areas of the world with high production of soya beans and corn: its relationship to crop yields
Authors: Llano María Paula , Vargas Walter , Naumann Gustavo
Published: June 2011

An important goal of this work is to study the variability of corn and soya bean crop yields in four countries with large production and substantial commercial trade in these commodities. This problem can be investigated in terms of the role that these two crops play in food programmes and in terms of the use of both crops for energy production. Four countries were chosen and divided into six production areas. A climatic summary was made of the annual cycles of extreme temperatures and precipitation. Their assessment in agriculture programmes was likewise summarized. It is seen that the variability range of the temperatures and precipitation are broad and different for each region. This finding indicates the high adaptability of these crops. This concept of adaptability is used to compare the coefficients for precipitation and crop yield. Results of the study show that corn crops show less year‐to‐year variability than do soya bean crops. The United States and the northern part of China are the regions that best use the rain supply with respect to crop yield. Soya bean crops show a greater year‐to‐year variability in the ratio of precipitation to crop yields. Argentina, the United States and northern China are the areas that best use the rain supply. To compare crop yields with climatic variables in the different regions, three types of regression model were used. The best fit is obtained by using the maximum temperatures and accumulated precipitation for each growth stage over the growing season. Copyright © 2011 Royal Meteorological Society
Functional pectoralis minor muscle flap transplantation for reconstruction of thumb opposition: An anatomic study and clinical applications
Authors: Zhuang Yong‐Qing , Xiong Hong‐Tao , Fu Qiang , Jiang Hao‐Li , Fu Xiao‐Kuan , Du Dong , Tong Jing , Hung Leung‐Kim
Published: June 2011

In this report, we present the results of an anatomic study on the dimensions of the pectoralis minor muscle and its neurovascular supply in 10 adult human cadavers, in attempt to evaluate the feasibility of microsurgical transplantation of a part of the muscle for thumb opposition reconstruction. A series of five patients consequently underwent thenar reconstruction with the pectoralis minor muscle flap from December 2004 to October 2006. The transferred muscle was reinnervated with the third lumbrical branch of the ulnar nerve. Follow‐up assessment showed that the patients recovered functional opposition of carpometacarpal joint with 24 degrees of pronation, and a muscle power with M4 to M5. All patients were satisfied with the appearance of reconstructed thenar eminence. We recommend this new technique for thenar and opposition reconstruction in patients who have severe loss of thenar muscles, injury to the median nerve, and wish to improve the appearance of thenar eminence. © 2011 Wiley‐Liss, Inc. Microsurgery, 2011.
Acrolein scavengers: Reactivity, mechanism and impact on health
Authors: Zhu Qin , Sun Zheng , Jiang Yue , Chen Feng , Wang Mingfu
Published: June 2011

Acrolein (ACR) is an α,β‐unsaturated aldehyde that exists extensively in the environment and (thermally processed) foods. It can also be generated through endogenous metabolism. Its high electrophilicity makes this aldehyde notorious for its facile reaction with biological nucleophiles, leading to the modification of proteins/DNA and depletion of glutathione. Recent studies also have revealed its roles in disturbing various cell signing pathways in biological systems. With growing evidences of ACR's implication in human diseases, strategies to eliminate its hazardous impacts are of great importance. One of the intervention strategies is the application of reactive scavengers to directly trap ACR. Some known ACR scavengers include sulfur (thiol)‐containing and nitrogen (amino)‐containing compounds as well as the newly emerging natural polyphenols. In this review, the interactions between ACR and its scavengers are highlighted. The discussion about ACR scavengers is mainly focused on their chemical reactivity, trapping mechanisms as well as their roles extended to biological relevance. In addition to their direct trapping effect on ACR, these scavengers might possess multiple functions and offer additional benefits against ACR‐induced toxicity. A comprehensive understanding of the mechanism involved may help to establish ACR scavenging as a novel therapeutic intervention against human diseases that are associated with ACR and/or oxidative stress.
Rapid quantification of myocardial lipid content in humans using single breath‐hold 1H MRS at 3 Tesla
Authors: Rial Belen , Robson Matthew D. , Neubauer Stefan , Schneider Jürgen E.
Published: June 2011

A rapid, proton magnetic resonance spectroscopy method to evaluate human myocardial lipid levels in a single breath‐hold at 3 T using a commercial whole‐body system is presented. During a 10 s breath‐hold, water unsuppressed and suppressed spectra were acquired by two phased array coils using a short‐echo time spectroscopic stimulated echo (STEAM) sequence electrocardiogram‐triggered to mid‐diastole. Lipid‐to‐water ratios were obtained in the septum of 15 healthy volunteers, (0.46 ± 0.19)%. These results agreed well with ratios obtained from averaged spectra acquired in seven multiple breath‐holds, (0.45 ± 0.20)%, providing increased signal‐to‐noise ratio but requiring longer acquisition times. Excellent correlation was found between the two methods (r = 0.94, P < 0.05). Reproducibility of 1H MRS for measuring myocardial lipid levels in a short breath‐hold was acceptable in five repeated measurements within the same subject (coefficient of variation = 19%). Thus, single breath‐hold proton spectroscopy allows reliable and quick quantification of myocardial lipids at 3 T. Magn Reson Med, 2011. © 2011 Wiley‐Liss, Inc.
Parallel imaging with asymmetric acceleration to reduce Gibbs artifacts and to increase signal‐to‐noise ratio of the gradient echo echo‐planar imaging sequence for functional MRI
Authors: Jung Kwan‐Jin , Zhao Tiejun
Published: June 2011

Parallel imaging with accelerated acquisition was noted to pronounce Gibbs artifacts which appear as ripples propagated in the phase‐encoding (PE) direction near the susceptibility‐affected region in echo‐planar imaging (EPI). Using the extended EPI sequence, which collected extended readouts outside the regular data sampling time, the pronounced Gibbs artifact was analyzed and found to be caused by an increased echo shift in the pre‐echo time (TE) of accelerated parallel imaging. This was also confirmed by theoretical derivation of the echo shift caused by the inplane susceptibility gradient in the PE direction (ISGPE). A new EPI sequence was developed to reduce the Gibbs artifact and to restore the signal level toward that of nonaccelerated parallel imaging by asymmetrically accelerating only the post‐TE sampling time and by using the extended EPI in the pre‐TE. The nonaccelerated portion in the pre‐TE used the delay for the optimum blood oxygen level dependent (BOLD) sensitivity at 3 T, maintaining the same slice coverage as the symmetrical acceleration in both pre‐TE and post‐TE. The increased data sampling points resulted in an increase of the signal‐to‐noise ratio (SNR). The restored signal and enhanced SNR of the proposed method were confirmed to deliver a better BOLD functional MRI (fMRI) result in the breath holding experiment. Magn Reson Med, 2012. © 2011 Wiley Periodicals, Inc.
In vivo iron quantification in collagenase‐induced microbleeds in rat brain
Authors: McAuley Grant , Schrag Matthew , Barnes Samuel , Obenaus Andre , Dickson April , Kirsch Wolff
Published: June 2011

Brain microbleeds (BMB) are associated with chronic and acute cerebrovascular disease. Because BMB present in the brain is a source of potentially cytotoxic iron proportional to the volume of extravasated blood, BMB iron content is a potentially valuable biomarker both to assess tissue risk and small cerebral vessel health. We recently reported methods to quantify focal iron sources using phase images that were tested in phantoms and BMB in postmortem tissue. In this study, we applied our methods to small hemorrhagic lesions induced in the in vivo rat brain using bacterial collagenase. As expected by theory, measurements of geometric features in phase images correlated with lesion iron content measured by graphite furnace atomic absorption spectrometry. Iron content estimation following BMB in an in vivo rodent model could shed light on the role and temporal evolution of iron‐mediated tissue damage and efficacy of potential treatments in cerebrovascular diseases associated with BMB. Magn Reson Med, 2012. © 2011 Wiley Periodicals, Inc.
A hybrid method for more efficient channel‐by‐channel reconstruction with many channels
Authors: Huang Feng , Lin Wei , Duensing George R. , Reykowski Arne
Published: June 2011

In MRI, imaging using receiving coil arrays with a large number of elements is an area of growing interest. With increasing channel numbers for parallel acquisition, longer reconstruction times have become a significant concern. Channel reduction techniques have been proposed to reduce the processing time of channel‐by‐channel reconstruction algorithms. In this article, two schemes are combined to enable faster and more accurate reconstruction than existing channel reduction techniques. One scheme use two stages of channel reduction instead of one. The other scheme is to incorporate all acquired data into the final reconstruction. The combination of these two schemes is called flexible virtual coil. Applications of flexible virtual coil for partially parallel imaging, motion compensation, and compressed sensing are presented as specific examples. Theoretical analysis and experimental results demonstrate that the proposed method has a major impact in reducing computation cost in reconstruction with high‐channel count coil elements. Magn Reson Med, 2012. © 2011 Wiley Periodicals, Inc.
Exogenously administered bombesin and gastrin releasing peptide contract the female rat urethra in vivo and in vitro
Authors: Radziszewski P. , Crayton R. , Persson K. , Andersson K.‐E. , Mattiasson A.
Published: June 2011

Background

Bombesin (BOM) and gastrin releasing peptide (GRP) have been located to the lower urinary tract (LUT). However, there is a paucity of data demonstrating the impact of these endogenous peptides.

Objectives

The aim of the present study was to investigate the contractile actions of BOM and GRP on the female rat urethra in vitro and in vivo. Female Sprague–Dawley rats (n = 37) weighing approximately 225 g were used. Intraurethral pressure was recorded by a catheter placed at the maximum pressure zone corresponding to the intrinsic urethral sphincter.

Measurements

In vitro, changes in intraurethral pressure was conducted on perfused intact urethral/bladder preparations and are expressed as percentages of sphincteric intraurethral pressure achieved with noradrenaline. In vivo, changes in intraurethral pressure was conducted in anesthetized subjects and compared with the baseline intraurethral pressure and sham controls.

Results

In vitro, the increase in intraurethral pressure induced by BOM was 23.6 ± 3.2 cmH2O, exceeding the pressure evoked with NA by 9.6 cmH2O or 174.4% whereas GRP induced a maximum pressure of 10.7 ± 1.6 cmH2O, an increase of 2.2 ± 0.5 cmH2O or 82.9% (P < 0.05) of the NA evoked pressure. In vivo, the mean baseline pressure was 22.9 ± 1.4 cmH2O. The intraurethral pressure evoked by BOM was 50.6 ± 6.3 cmH2O (P < 0.05), and for GRP, the evoked intraurethral pressure was 56.2 ± 13.4 cmH2O (P < 0.05).

Conclusions

The present data suggest that both BOM and GRP may contribute to the control of continence by their contractile action on the sphincters of the LUT outflow region. Neurourol. Urodynam. 30:1388–1391, 2011. © 2011 Wiley‐Liss, Inc.
Exogenously administered bombesin and gastrin releasing peptide contract the female rat urethra in vivo and in vitro
Authors: Radziszewski Piotr , Crayton Robert , Persson Katarina , Andersson Karl‐Erik , Mattiasson Anders
Published: June 2011

Background

Bombesin (BOM) and gastrin releasing peptide (GRP) have been located to the lower urinary tract. However, there is a paucity of data demonstrating the impact of these neuropeptides.

Objectives

The present study investigates the impact of BOM and GRP in the female Sprague–Dawley rats 225 g b.w. n = 37 urethras in vitro and in vivo. Intraurethral pressure was recorded by a catheter placed at the maximum pressure zone corresponding to the intrinsic urethral spincter.

Measurements

In vitro, the intraurethral pressure was measured in response to the administration of BOM and GRP and noradrenaline from perfused intact urethral/bladder preparations. In vivo, changes in intraurethral pressure were conducted in anesthetized subjects and compared with the basal intraurethral pressure and sham controls.

Results

In vitro, the increase in intraurethral pressure induced by BOM was 23.6 ± 3.2 cmH2O, exceeding the pressure evoked with NA by 10.7 cmH2O whereas GRP induced 10.7 ± 1.6 cmH2O, an increase of 3.3 cmH2O but less than the NA evoked intraurethral pressure by 2.2 cmH2O. Incubation with scopolamine (1 µM), phentolamine (1 µM), pancuronium (1 µM), and indomethacin (1 µM) did not produce any significant difference in the contractile responses to BOM or GRP. In vivo, the mean basal pressure was 22.9 ± 1.4 cmH2O. The intraurethral pressure evoked by BOM was 29.7 cmH2O (21.3 ± 1.3 to 51.0 ± 1.6 cmH2O), and for GRP, the evoked intraurethral pressure was 33.8 cmH2O (22.3 ± 1.9 to 56.2 ± 30 cmH2O).

Conclusions

BOM and GRP may contribute to the control of continence by their contractile action on the sphincters of the lower urinary tract outflow region. Neurourol. Urodynam. Neurourol. Urodynam. 30: 1681–1685, 2011. © 2011 Wiley Periodicals, Inc.
Consecutive vesicovaginal fistula for transobturator sling perforations and successful repairs with skin flap
Authors: Bajory Zoltan , Fekete Zoltan , Kiraly Istvan , Szalay Istvan , Pajor Laszlo
Published: June 2011

Aim

To report a reconstructive technique of large vesicovaginal fistula repairs, which is a rare complication of the most modern anti‐incontinence procedures (tension‐free tapes) using the “oldie but goodie” Lehoczky's island flap.

Methods

Women with large vesicovaginal fistulas caused by mid‐urethral transobturator tape were operated in our department. The transobturator tape was removed and the large fistula was closed using the skin island flap. The flap was created from the regional skin and subcutaneous tissue and pulled with intact vascular supply through a paravaginal tunnel to the site of the vaginal defect.

Results

No complications occurred after the reconstructions. The patients have become permanently continent and free from fistulas.

Conclusions

Mid‐urethral transobturator sling is a successful procedure evidenced worldwide with a very low rate of fistula formation. Lehoczky's island flap can be a reasonable and safe surgical option in the repair of large defects of the vaginal wall. Neurourol. Urodynam. Neurourol. Urodynam. 30: 1530–1532, 2011. © 2011 Wiley Periodicals, Inc.
Electrical stimulation for lower urinary tract dysfunction in children: A systematic review of the literature
Authors: Barroso Ubirajara , Tourinho Rafael , Lordêlo Patrícia , Hoebeke Piet , Chase Janet
Published: June 2011

Aims

To review studies using electrical neural stimulation (ENS), to treat children with non‐neurogenic lower urinary tract dysfunctions (LUTD), and to establish the efficacy of this treatment.

Methods

This review was based on an electronic search of the MEDLINE database and the Cochrane Central Search library, from January 1990 to March 2010. Inclusion criteria: (1) participants aged 0–17 years, (2) participants with a diagnosis of LUTD not related to congenital abnormalities or neurological disease, (3) English language, and (4) treatment by ENS.

Results

Seventeen papers were evaluated. Type of ENS varied among studies: sacral transcutaneous ENS in seven, sacral implanted device in four, posterior tibial percutaneous in three, and anogenital, endoanal, and intravesical in one each. There were two randomized clinical trials. Clarity regarding the LUTD being treated was variable. The populations studied were not homogeneous. The duration of treatment and the number of sessions a week were variable among the studies. Electrical parameters used also varied. A range of subjective and objective measures was used to measure treatment success. Rates of complete resolution of the symptoms of OAB, urgency, and daytime incontinence ranged from 31% to 86% [Trsinar and Kraij, Neurourol Urodyn 15: 133–42, 1996; Hagstroem et al., J Urol 182: 2072–8, 2009], 25% to 84% [Hoebeke et al., J Urol 168: 2605–8, 2002; Lordêlo et al., J Urol 182: 2900–4, 2009], 13% to 84% [Malm‐Buatsi et al., Urology 70: 980–3, 2007; Lordêlo et al., J Urol 184: 683–9, 2010], respectively. For sacral transcutaneous ENS recurrence ranged from 10% to 25%. Apart from the sacral implantation studies, any reported side effects were mild and transitory.

Conclusions

The literature in the area of interest is sparse. Parasacral TENS has been shown to be more effective than sham in randomized trials in treating OAB. This deserves further research to elucidate the optimal parameters and the children for whom it is most useful. Neurourol. Urodynam. Neurourol. Urodynam. 30: 1429–1436, 2011. © 2011 Wiley Periodicals, Inc.
Effect of repeated detrusor onabotulinumtoxina injections on bladder and renal function in patients with chronic spinal cord injuries
Authors: Kuo Hann‐Chorng , Liu Shu‐Hsin
Published: June 2011

Aims

To investigate the therapeutic effects of repeated detrusor onabotulinumtoxinA injections on urinary incontinence and renal function in patients with chronic spinal cord injuries (SCI).

Methods

Patients with suprasacral SCI were enrolled. OnabotulinumtoxinA 200 U detrusor injections were repeated every 6 months for four times. Patients were instructed to perform clean intermittent catheterization during the treatment and follow‐up periods. Videourodynamic study and 99mTc‐DTPA renal scanning for glomerular filtration rate (GFR) were performed at screening and every 3 months to assess the therapeutic effects on bladder and renal function. Quality of life was measured by the UDI‐6, IIQ‐7, and self‐assessed QoL indices. Adverse events were also recorded.

Results

A total of 33 patients completed the study, 30 had improvement in incontinence grade (n = 18) or became completely dry (n = 12) after initial and subsequent onabotulinumtoxinA injections. Mean bladder capacity increased from 207 ± 111 to 412 ± 33 ml and mean detrusor pressure decreased from 39.8 ± 21.7 to 20.6 ± 19.1 cmH2O (all P < 0.05). However, the mean GFR decreased from 93.4 ± 20.4 to 83.5 ± 24 ml/min (P = 0.028). A significant reduction in GFR was noted in patients with bladder compliance that increased by <10 cmH2O (P = 0.002) and in patients with Pdet decreased by <10 cmH2O after treatment (P = 0.036). All 30 patients with improvement in incontinence grade satisfied with treatment result.

Conclusion

This pilot study revealed that repeated detrusor injections of 200 U onabotulinumtoxinA could reduce incontinence grade, increase bladder capacity, and decrease intravesical pressure but this study did not demonstrate an improvement in GFR over a 24‐month period in patients with chronic SCI. Neurourol. Urodynam. Neurourol. Urodynam. 30: 1541–1545, 2011. © 2011 Wiley Periodicals, Inc.
Evidence for autonomic nervous system dysfunction in females with idiopathic overactive bladder syndrome
Authors: Hubeaux Katelyne , Deffieux Xavier , Raibaut Patrick , Le Breton Frédérique , Jousse Marylène , Amarenco Gérard
Published: June 2011

Aims

Micturition and continence are largely under the control of the autonomic nervous system (ANS). In this study, we analyzed ANS function using autonomic cardiovascular (CV) testing in females with idiopathic overactive bladder syndrome (iOAB) versus control females. Our hypothesis was that ANS dysfunction could comprise part of the pathophysiology of iOAB.

Methods

Twenty‐three females with iOAB and 29 controls were enrolled into this prospective study. Patients performed CV autonomic testing, including two sympathetic tests (hand grip exercise and cold pressor test), two parasympathetic tests (deep breathing and 30:15 ratio), and two mixed tests (Valsalva manoeuvre and blood pressure [BP] response to standing). Patients with iOAB also underwent conventional urodynamic studies in order to define iOAB as either with or without demonstrable detrusor overactivity (DO).

Results

Both groups were similar with respect to age and menopausal status. Females with iOAB had significantly more positive tests than controls (P < 0.0001), particularly for sympathetic tests (P < 0.0001). Among the iOAB group, the sympathetic tests (P = 0.03) were significantly more often positive in patients without DO (based on cystometry) compared to patients with DO, with the results being particularly significant for the cold pressor test (P = 0.02). No differences were found among iOAB sufferers with respect to a past history of enuresis.

Conclusions

These results suggest ANS dysfunction, predominantly a sympathetic ANS dysfunction, is associated with iOAB, specifically in patients with iOAB without DO. Neurourol. Urodynam. Neurourol. Urodynam. 30: 1467–1472, 2011. © 2011 Wiley Periodicals, Inc.