bluuebunny/crossref_metadata_2025 huggingface dataset:
Solid‐state NMR to evaluate the molecular changes in the mango starch after 8 years of storage
Authors: Bathista André Luis Bonfim Silva , Silva Emerson Oliveira da , Tavares Maria Inês Bruno , Prado Rogério Junqueira
Published: March 2012

Mango seed starch was mainly investigated by 1D solid state nuclear magnetic resonance (NMR) to evaluate the changes in the chemical structure and molecular dynamic, as a response of time storage. X‐ray diffraction was used to accompany changes in the morphology after time storage. Thus, the basic work was to understand the changes of mango seed starch, after 8 years storage at room conditions. The solid‐state NMR and X‐ray diffraction results showed that no changes in both chemical structure and molecular dynamic as well as morphology was found after 8 years of being storage at room conditions. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Wetland habitats of the Sabana de Bogotá Andean Highland Plateau and their birds
Authors: Rosselli Loreta , Stiles F. Gary
Published: March 2012

The Sabana de Bogotá highland plateau is located in the eastern Andes wetland complex of Colombia, a biogeographically important and highly degraded area where little is known about the general habitat availability and requirements for wildlife based on comparative studies.

This study sought to identify the environmental factors that best explained the richness and composition of bird communities in the area's wetlands.

GIS and remote images were used to measure landscape and local habitat variables along with the presence of birds in 19 varied wetlands of the Sabana.

A high variation in wetland characteristics, related to their urban or rural status, was found. Aquatic bird richness was associated with wetland area; guilds such as waders that probe in mud, walkers on aquatic vegetation, and shoreline walkers tended to be richer in large wetlands with extensive emergent vegetation cover. Other guilds (waders that wait to stalk, flight feeders and surface swimmers) were more related to open water areas.

It is concluded that the remaining large wetlands should have a high priority for conservation but the set of small natural and artificial wetlands are also important in the maintenance of high habitat heterogeneity, bird populations and regional diversity. Copyright © 2012 John Wiley & Sons, Ltd.
Ethanol‐glycerin fixation with thymol conservation: A potential alternative to formaldehyde and phenol embalming
Authors: Hammer Niels , Löffler Sabine , Feja Christine , Sandrock Mara , Schmidt Wolfgang , Bechmann Ingo , Steinke Hanno
Published: March 2012

Anatomical fixation and conservation are required to prevent specimens from undergoing autolysis and decomposition. While fixation is the primary arrest of the structures responsible for autolysis and decomposition, conservation preserves the state of fixation. Although commonly used, formaldehyde has been classified as carcinogenic to humans. For this reason, an adequate substitute was developed. Ethanol‐glycerin fixation and thymol conservation are described and compared with formaldehyde and phenol in this technical report. The setup, tissue qualities, financial aspects, and health concerns of this method are discussed. Ethanol‐glycerin fixation and thymol conservation provide outstanding haptic and optic tissue qualities. Typical formaldehyde and phenol effects, such as skin, airway, and eye irritation, as well as carcinogenic effects, can be circumvented by using ethanol‐glycerin and thymol instead. Ethanol‐glycerin fixation is more expensive than formaldehyde and requires an explosion‐proof facility. However, the absence of health effects and its convincing tissue qualities balance these higher costs. Therefore, ethanol‐glycerin fixation and thymol conservation provide a potential alternative and complement established fixation techniques. The use of carcinogenic formaldehyde and toxic phenol can be effectively restricted through the use of the described method. Anat Sci Educ. © 2012 American Association of Anatomists.
A reliability‐based traffic assignment model for multi‐modal transport network under demand uncertainty
Authors: Fu Xiao , Lam William H. K. , Chen Bi Yu
Published: March 2012

In densely populated and congested urban areas, the travel times in congested multi‐modal transport networks are generally varied and stochastic in practice. These stochastic travel times may be raised from day‐to‐day demand fluctuations and would affect travelers' route and mode choice behaviors according to their different expectations of on‐time arrival. In view of these, this paper presents a reliability‐based user equilibrium traffic assignment model for congested multi‐modal transport networks under demand uncertainty. The stochastic bus frequency due to the unstable travel time of bus route is explicitly considered. By the proposed model, travelers' route and mode choice behaviors are intensively explored. In addition, a stochastic state‐augmented multi‐modal transport network is adopted in this paper to effectively model probable transfers and non‐linear fare structures. A numerical example is given to illustrate the merits of the proposed model. Copyright © 2012 John Wiley & Sons, Ltd.
Scheduling highway work zones with genetic algorithm considering the impact of traffic diversion
Authors: Chien Steven I‐Jy , Tang Yimin
Published: March 2012

Highway work zones caused excessive delay to road users. To reduce user and maintenance costs, work zones shall be designed and scheduled accordingly. An analytical model is developed to jointly optimize work zone lengths and schedule as well as diverted traffic volume for highway maintenance projects, considering time‐varying demand, variable maintenance cost, and various production rates of maintenance crew. With a genetic algorithm, an iterative procedure is developed to search for the optimal solution. A numerical example is illustrated, in which various traffic mitigation plans for a highway maintenance project are evaluated. A sensitivity analysis is conducted, and results indicate the threshold volumes for various conditions (e.g., maintenance crews and capacity of the work zone) at which diverting traffic is desirable. This study demonstrates an effective approach to search for the optimal work zone schedule, which is also applicable to evaluate the effectiveness of traffic diversion plans for a pre‐planned work zone schedule. Copyright © 2012 John Wiley & Sons, Ltd.
Teratogen update: Methotrexate
Authors: Hyoun Sara C. , Običan Sarah G. , Scialli Anthony R.
Published: March 2012

Methotrexate and aminopterin are folic acid antagonists that inhibit dihydrofolate reductase, resulting in a block in the synthesis of thymidine and inhibition of DNA synthesis. Methotrexate has been used for the treatment of malignancy, rheumatic disorders, and psoriasis and termination of intrauterine pregnancy. Recently, methotrexate has become a standard treatment for ectopic pregnancy. The misdiagnosis of an intrauterine pregnancy as an ectopic pregnancy can result in exposure of a continuing pregnancy to dose levels of methotrexate of 50 mg/m2 (maternal body surface area). Experimental animal studies have associated methotrexate therapy with embryo death in mice, rats, rabbits, and monkeys. Structural malformations have been most consistently produced in rabbits at a maternal dose level of 19.2 mg/kg. Abnormalities in rabbits include hydrocephalus, microphthalmia, cleft lip and palate, micrognathia, dysplastic sacral and caudal vertebrate, phocomelia, hemimelia, syndactyly, and ectrodactyly. Based on human case reports of methotrexate exposure during pregnancy, a methotrexate embryopathy has been described that includes growth deficiency, microcephaly, hypoplasia of skull bones, wide fontanels, coronal or lambdoidal craniosynostosis, upswept frontal scalp hair, broad nasal bridge, shallow supraorbital ridges, prominent eyes, low‐set ears, maxillary hypoplasia, epicanthal folds, short limbs, talipes, hypodactyly, and syndactyly. This syndrome may be associated with exposures between 6 and 8 weeks after conception and dose levels of 10 mg/week or greater. More recent case reports of methotrexate exposure for the misdiagnosis of ectopic pregnancy involve treatment before 6 weeks after conception and have raised the suggestion of a distinct syndrome due to such early exposures. Tetralogy of Fallot and perhaps other neural crest cell‐related abnormalities may be features of this early syndrome. A disproportionality analysis of methotrexate and aminopterin case reports and series provides support for pulmonary atresia, craniosynostosis, and limb deficiencies as reported more often than expected in methotrexate‐exposed children. Denominator‐based data will be welcome to better define elements of a methotrexate embryopathy and possibly to distinguish an early exposure syndrome from anomalies traditionally associated with methotrexate exposure. Birth Defects Research (Part A), 2012. © 2012 Wiley Periodicals, Inc.
Parametric animation of performance‐captured mesh sequences
Authors: Casas Dan , Tejera Margara , Guillemaut Jean‐Yves , Hilton Adrian
Published: March 2012

In this paper, we introduce an approach to high‐level parameterisation of captured mesh sequences of actor performance for real‐time interactive animation control. High‐level parametric control is achieved by non‐linear blending between multiple mesh sequences exhibiting variation in a particular movement. For example, walking speed is parameterised by blending fast and slow walk sequences. A hybrid non‐linear mesh sequence blending approach is introduced to approximate the natural deformation of non‐linear interpolation techniques whilst maintaining the real‐time performance of linear mesh blending. Quantitative results show that the hybrid approach gives an accurate real‐time approximation of offline non‐linear deformation. An evaluation of the approach shows good performance not only for entire meshes but also with specific mesh areas. Results are presented for single and multi‐dimensional parametric control of walking (speed/direction), jumping (height/distance) and reaching (height) from captured mesh sequences. This approach allows continuous real‐time control of high‐level parameters such as speed and direction whilst maintaining the natural surface dynamics of captured movement. Copyright © 2012 John Wiley & Sons, Ltd.
Interleukin 6 protects H2O2‐induced cardiomyocytes injury through upregulation of prohibitin via STAT3 phosphorylation
Authors: Jia Yuhua , Zhou Fenghua , Deng Peng , Fan Qin , Li Chunhua , Liu Yawei , Fu Xiuqiong , Zhou Yingchun , Xu Xin , Sun Xuegang
Published: March 2012

Objective: Hydrogen peroxide (H2O2) is a potent reactive oxygen species that causes cardiomyocytes injury. As an important cytokine, interleukin 6 (IL‐6) has cardioprotective effects as it plays an essential role in the late phase of preconditioning. Our work is to investigate if IL‐6 preconditioning has protective effects on neonatal rat ventricular cardiomyocytes in response to H2O2 and its underlying mechanism. Methods: Gel‐based comparative proteomic approach along with small interfering RNA (siRNA) and Western blot analysis was used to analyse mechanisms of IL‐6 preconditioning on H2O2‐induced neonatal rat ventricular cardiomyocytes injury. Results: IL‐6 preconditioning protected cardiomyocytes against H2O2‐induced cell death. Proteomic analysis showed that IL‐6 pretreatment further increased the expression of prohibitin and improved the viability of cardiomyocytes exposed to H2O2. Knocking down of prohibitin with siRNA abrogated this protection by increasing apoptosis rate. Tyrosine kinase inhibitor AG490 decreased signal transducers and activators of transcription 3 (STAT3) phosphorylation and down‐regulated prohibitin expression in cardiomyocytes pretreated with IL‐6 and exposed to H2O2, which further dampened the protective effects of IL‐6 preconditioning. Conclusion: Our results provide direct evidence that prohibitin is a protective factor of IL‐6 preconditioning in H2O2‐induced neonatal rat ventricular cardiomyocytes death. The upregulation of prohibitin by IL‐6 is, at least, partially regulated through STAT3 phosphorylation. Copyright © 2012 John Wiley & Sons, Ltd.
β‐amyloid decreases detectable endothelial nitric oxide synthase in human erythrocytes: a role for membrane acetylcholinesterase
Authors: Misiti Francesco , Carelli‐Alinovi Cristiana , Sampaolese Beatrice , Giardina Bruno
Published: March 2012

Until few years ago, many studies of Alzheimer's disease investigated the effects of this syndrome in the central nervous system. Only recently, the detection of amyloid beta peptide (Aβ) in the blood has evidenced the necessity to extend studies on extraneuronal cells, particularly on erythrocytes. Aβ is also present in brain capillaries, where it interacts with the erythrocytes, inducing several metabolic and functional alterations. Recently, functionally active endothelial type nitric oxide synthase (eNOS) was discovered in human erythrocytes. The goal of the present study was to evidence the effect of Aβ on erythrocyte eNOS. We found that Aβ following to 24‐h exposure causes a decrease in the immune staining of erythrocyte eNOS. Concurrently, Aβ alters erythrocyte cell morphology, decreases nitrites and nitrates levels, and affects membrane acetylcholinesterase activity. Propidium, an acetylcholinesterase inhibitor, was able to reverse the effects elicited by Aβ. These events could contribute to the vascular alterations associated with Alzheimer's disease disease. Copyright © 2012 John Wiley & Sons, Ltd.
Antisolvent Precipitation for the Synthesis of Monodisperse Mesoporous Niobium Oxide Spheres as Highly Effective Solid Acid Catalysts
Authors: Li Cheng Chao , Dou Jian , Chen Luwei , Lin Jianyi , Zeng Hua Chun
Published: March 2012

We have developed a low‐cost reaction protocol to synthesize mesoporous Nb2O5‐based solid acid catalysts with external shape control. In the synthesis, monodisperse glycolated niobium oxide spheres (GNOS) were prepared by means of a simple antisolvent precipitation approach and subsequently converted to mesoporous niobium oxide spheres (MNOS) with a large surface area of 312 m2 g−1 by means of the hydrothermal treatment. The antisolvent acetone used to obtain GNOS was recovered through distillation at high purity. The obtained mesoporous MNOS were functionalized further with sulfate anions at different temperatures or incorporated with tungstophosphoric acid to obtain recyclable solid acid catalysts. These MNOS‐based catalysts showed excellent performance in a wide range of acid‐catalyzed reactions, such as Friedel–Crafts alkylation, esterification, and hydrolysis of acetates. As they are monodisperse spheres with diameters in the submicrometer range, the catalysts can be easily separated and reused.
Evaluation of target factor analysis and net analyte signal as processes for classification purposes with application to benchmark data sets and extra virgin olive oil adulterant identification
Authors: Higgins Kevin , Kalivas John H. , Andries Erik
Published: March 2012

Classifying samples into known categories is a common problem in analytical chemistry and other fields. For example, with spectroscopic data, samples are measured and the corresponding spectra are compared with existing spectral data sets of known classification (library sets) to determine the appropriate classification. Presented in this paper is a study of the simple and well known data analysis processes target factor analysis (TFA) and net analyte signal (NAS). Although TFA and NAS were originally derived for different purposes in analytical chemistry, they are based on the same calculation. The library set with the smallest TFA residual (smallest NAS) for a test sample spectrum can be used for classification purposes. Alternatively and equivalently, this paper uses the smallest angle (poorest selectivity in NAS terminology) between a new sample spectrum vector and the space spanned by each library loading vector basis set. The angle classification is compared with classifications by the Mahalanobis distance and k‐nearest neighbors. The measures are evaluated with three spectroscopic data sets consisting of benchmark identification of plastic type (Raman) and gasoil plant source (ultraviolet) and a new extra virgin olive oil adulterant identification (fluorescence) data set. A fourth data set is the benchmark archeological data set. The Mahalanobis distance and k‐nearest neighbors generally classify with 2%–40% and 0%–20% decreases in correct classifications, respectively, compared with TFA (NAS). Results from this study indicate that the simple TFA and NAS processes are useful underutilized classification and library searching tools. Copyright © 2012 John Wiley & Sons, Ltd.
Mechanism of the Transition‐Metal‐Catalyzed Hydroarylation of Bromo‐Alkynes Revisited: Hydrogen versus Bromine Migration
Authors: Huang Genping , Cheng Bing , Xu Liang , Li Yahong , Xia Yuanzhi
Published: March 2012

A comprehensive mechanistic study of the InCl3‐, AuCl‐, and PtCl2‐catalyzed cycloisomerization of the 2‐(haloethynyl)biphenyl derivatives of Fürstner et al. was carried out by DFT/M06 calculations to uncover the catalyst‐dependent selectivity of the reactions. The results revealed that the 6‐endo‐dig cyclization is the most favorable pathway in both InCl3‐ and AuCl‐catalyzed reactions. When AuCl is used, the 9‐bromophenanthrene product could be formed by consecutive 1,2‐H/1,2‐Br migrations from the Wheland‐type intermediate of the 6‐endo‐dig cyclization. However, in the InCl3‐catalyzed reactions, the chloride‐assisted intermolecular H‐migrations between two Wheland‐type intermediates are more favorable. These Cl‐assisted H‐migrations would eventually lead to 10‐bromophenanthrene through proto‐demetalation of the aryl indium intermediate with HCl. The cause of the poor selectivity of the PtCl2 catalyst in the experiments by the Fürstner group was predicted. It was found that both the PtCl2‐catalyzed alkyne–vinylidene rearrangement and the 5‐exo‐dig cyclization pathways have very close activation energies. Further calculations found the former pathway would lead eventually to both 9‐ and 10‐bromophenanthrene products, as a result of the Cl‐assisted H‐migrations after the cyclization of the Pt–vinylidene intermediate. Alternatively, the intermediate from the 5‐exo‐dig cyclization would be transformed into a relatively stable Pt–carbene intermediate irreversibly, which could give rise to the 9‐alkylidene fluorene product through a 1,2‐H shift with a 28.1 kcal mol−1 activation barrier. These findings shed new light on the complex product mixtures of the PtCl2‐catalyzed reaction.
Ellipsoidal TiO2 Hierarchitectures with Enhanced Photovoltaic Performance
Authors: Peng Wenqin , Yanagida Masatoshi , Chen Han , Han Liyuan
Published: March 2012

Hierarchical TiO2 ellipsoids 250–500 nm in size have been synthesized on a large scale by a template‐free hydrothermal route. The submicrometer‐sized hierarchitectures are assembled from highly crystallized anatase nanorods about 17 nm in diameter with macroporous cavities on the outer shells. Based on the time‐dependent morphological evolution under hydrothermal conditions, an oriented attachment process is proposed to explain formation of the hierarchical structures. Such hierarchical TiO2 not only adsorbs large amounts of dye molecules due to high surface area, but also shows good light scattering caused by the submicrometer size. The TiO2 hierarchitectures were deposited on top of a transparent TiO2 nanocrystalline main layer to construct a double‐layered photoanode for dye‐sensitized solar cell (DSC) application, exhibiting enhanced light harvesting and power‐conversion efficiency compared to a commercial TiO2‐based electrode.
Metamagnetism and Single‐Chain Magnetic Behavior in a Homospin One‐Dimensional Iron(II) Coordination Polymer
Authors: Boeckmann Jan , Wriedt Mario , Näther Christian
Published: March 2012

Reaction of FeCl2⋅4 H2O with KNCSe and pyridine in ethanol leads to the formation of the discrete complex [Fe(NCSe)2(pyridine)4] (1) in which the FeII cations are coordinated by two N‐terminal‐bonded selenocyanato anions and four pyridine co‐ligands. Thermal treatment of compound 1 enforces the removal of half of the co‐ligands leading to the formation of a ligand‐deficient (lacking on neutral co‐ligands) intermediate of composition [Fe(NCSe)2(pyridine)2]n (2) to which we have found no access in the liquid phase. Compound 2 is obtained only as a microcrystalline powder, but it is isotypic to [Cd(NCSe)2(pyridine)2]n and therefore, its structure was determined by Rietveld refinement. In its crystal structure the metal cations are coordinated by two pyridine ligands and four selenocyanato anions and are linked into chains by μ‐1,3 bridging anionic ligands. Magnetic measurements on compound 1 show only paramagnetic behavior, whereas for compound 2 an unexpected magnetic behavior is found, which to the best of our knowledge was never observed before for a iron(II) homospin compound. In this compound metamagnetism and single‐chain magnetic behavior coexist. The metamagnetic transition between the antiferromagnetically ordered phase and a field‐induced ferromagnetic phase of the high‐spin iron(II) spin carriers is observed at a transition field HC of 1300 Oe and the single‐chain magnetic behavior is characterized by a blocking temperature TB, estimated to be about 5 K.
A Combined Solid‐State NMR and X‐ray Crystallography Study of the Bromide Ion Environments in Triphenylphosphonium Bromides
Authors: Burgess Kevin M. N. , Korobkov Ilia , Bryce David L.
Published: March 2012

Multinuclear (31P and 79/81Br), multifield (9.4, 11.75, and 21.1 T) solid‐state nuclear magnetic resonance experiments are performed for seven phosphonium bromides bearing the triphenylphosphonium cation, a molecular scaffold found in many applications in chemistry. This is undertaken to fully characterise their bromine electric field gradient (EFG) tensors, as well as the chemical shift (CS) tensors of both the halogen and the phosphorus nuclei, providing a rare and novel insight into the local electronic environments surrounding them. New crystal structures, obtained from single‐crystal X‐ray diffraction, are reported for six compounds to aid in the interpretation of the NMR data. Among them is a new structure of BrPPh4, because the previously reported one was inconsistent with our magnetic resonance data, thereby demonstrating how NMR data of non‐standard nuclei can correct or improve X‐ray diffraction data. Our results indicate that, despite sizable quadrupolar interactions, 79/81Br magnetic resonance spectroscopy is a powerful characterisation tool that allows for the differentiation between chemically similar bromine sites, as shown through the range in the characteristic NMR parameters. 35/37Cl solid‐state NMR data, obtained for an analogous phosphonium chloride sample, provide insight into the relationship between unit cell volume, nuclear quadrupolar coupling constants, and Sternheimer antishielding factors. The experimental findings are complemented by gauge‐including projector‐augmented wave (GIPAW) DFT calculations, which substantiate our experimentally determined strong dependence of the largest component of the bromine CS tensor, δ11, on the shortest BrP distance in the crystal structure, a finding that has possible application in the field of NMR crystallography. This trend is explained in terms of Ramsey’s theory on paramagnetic shielding. Overall, this work demonstrates how careful NMR studies of underexploited exotic nuclides, such as 79/81Br, can afford insights into structure and bonding environments in the solid state.
Correspondence of RuIIIRuII and RuIVRuIII Mixed Valent States in a Small Dinuclear Complex
Authors: Agarwala Hemlata , Scherer Thomas Michael , Maji Somnath , Mondal Tapan Kumar , Mobin Shaikh M. , Fiedler Jan , Urbanos Francisco A. , Jiménez‐Aparicio Reyes , Kaim Wolfgang , Lahiri Goutam Kumar
Published: March 2012

The diruthenium(III) compound [(μ‐oxa){Ru(acac)2}2] [1, oxa2−=oxamidato(2−), acac−=2,4‐pentanedionato] exhibits an S=1 ground state with antiferromagnetic spin‐spin coupling (J=−40 cm−1). The molecular structure in the crystal of 1⋅2 C7H8 revealed an intramolecular metal–metal distance of 5.433 Å and a notable asymmetry within the bridging ligand. Cyclic voltammetry and spectroelectrochemistry (EPR, UV/Vis/NIR) of the two‐step reduction and of the two‐step oxidation (irreversible second step) produced monocation and monoanion intermediates (Kc=105.9) with broad NIR absorption bands (ε ca. 2000 M−1 cm−1) and maxima at 1800 (1−) and 1500 nm (1+). TD‐DFT calculations support a RuIIIRuII formulation for 1− with a doublet ground state. The 1+ ion (RuIVRuIII) was calculated with an S=3/2 ground state and the doublet state higher in energy (ΔE=694.6 cm−1). The Mulliken spin density calculations showed little participation of the ligand bridge in the spin accommodation for all paramagnetic species [(μ‐oxa){Ru(acac)2}2]n, n=+1, 0, −1, and, accordingly, the NIR absorptions were identified as metal‐to‐metal (intervalence) charge transfers. Whereas only one such NIR band was observed for the RuIIIRuII (4d5/4d6) system 1−, the RuIVRuIII (4d4/4d5) form 1+ exhibited extended absorbance over the UV/Vis/NIR range.
Electrochemically Active Cross‐Linking Reaction for Fluorescent Labeling of Aliphatic Alkenes
Authors: Kim Shokaku , Hirose Kumi , Uematsu Jumpei , Mikami Yuzuru , Chiba Kazuhiro
Published: March 2012

Although cross‐linking reactions serve as a valuable tool for the integration of two or more functionalities or properties, the application of electrochemical synthesis to cross‐linking reactions is restricted due to the difficulty of mass transfer. Thus, the primary purpose of this research is to explore electrochemical cross‐linking systems to construct a fluorescent probe, triggered by the formation of a covalent linkage. The second purpose is to apply the probe to insoluble targets. Towards these goals, a combination of electrochemically active phenol derivatives and aliphatic alkenes were employed to form polycyclic compounds. Several of the dihydrobenzofuran derivatives formed through [3+2] cyclization reactions exhibited fluorescence. Furthermore, this approach allowed the effective modification of alkene‐modified silica gel with electrochemically active species, which enables the construction of fluorescent probes that are triggered by CC bond formation.
CCS Separation Techniques – Review on Existing Technologies and Developments
Authors: Scherer Viktor , Stolten Detlef , Franz Johannes , Riensche Ernst
Published: March 2012

Der folgende Beitrag fasst den Stand der Technik im Bereich der CO2‐Abscheidetechniken für kohlegefeuerte Kraftwerke zusammen und gibt einen Ausblick auf neuere Entwicklungen. Neben den bekannten Verfahren werden auch die Vor‐ und Nachteile membranbasierter Abscheidetechniken diskutiert sowie Chemical und Carbonate Looping, in denen ein Sauerstoff‐ oder CO2‐Trägermaterial im Kreislauf geführt wird, vorgestellt. Bei Verfahren, die auf heutigem Stand der Technik beruhen, ist mit Wirkungsgradverlusten in der Größenordnung von 10 %‐Punkten zu rechnen, wobei die Verdichtung auf Pipelinedruck schon eingerechnet ist. Neuere Entwicklungen lassen künftig Wirkungsgradverluste in der Größenordnung von 5 bis 10 %‐Punkten als realistisch erscheinen.
Agnes Pockels (1862 – 1935)
Authors: Mischnick Petra
Published: March 2012

Agnes Pockels (1862 – 1935) gehörte zu der Generation von Frauen in Deutschland, denen höhere Schulbildung und ein Universitätsstudium noch verwehrt blieb. Zu ihrem 150. Geburtstag schauen wir mit großem Respekt auf ihr autodidaktisch und neben häuslichen Pflichten geschaffenes wissenschaftliches Werk, das grundlegende Beiträge zur Erforschung der Oberflächeneigenschaften von Wasser lieferte. Nach ihr ist das SchülerInnen‐Labor der TU Braunschweig benannt, das seit 2002 Mädchen wie Jungen die Möglichkeit bietet, die Naturwissenschaften experimentierend für sich zu entdecken.
Interference with kinesin‐based anterograde neurofilament axonal transport increases neurofilament‐neurofilament bundling
Authors: Sunil Neethu , Lee Sangmook , Shea Thomas B.
Published: March 2012

Neurofilaments (NFs) associate with each other and with other cytoskeletal elements to form a lattice that supports the mature axon. Phosphorylation contributes to formation of this stationary population of NFs by fostering cation‐dependent interactions among NF sidearms. Association of NFs with the stationary phase indirectly competes with NF axonal transport by withdrawing NFs from kinesin‐dependent motility along microtubules. We therefore hypothesized that inhibition of anterograde NF transport may increase incorporation into the stationary phase. To test this hypothesis, we treated differentiated NB2a/d1 cells expressing GFP‐tagged NF subunits with monastrol, a specific inhibitor of kinesin‐5. Monastrol significantly inhibited anterograde axonal transport of NF‐H but not NF‐M, and increased the incorporation of newly‐transported NF subunits into axonal NF bundles. These findings support the notion that NF transport and bundling exert opposing forces on axonal NF dynamics, and that inhibition of anterograde transport of NFs can increase their incorporation into the stationary phase. © 2012 Wiley Periodicals, Inc
Functionalized single‐walled carbon nanotubes containing traces of iron as new negative MRI contrast agents for in vivo imaging
Authors: Doan Bich‐Thuy , Seguin Johanne , Breton Marie , Beherec Ronan Le , Bessodes Michel , Rodríguez‐Manzo Julio A. , Banhart Florian , Beloeil Jean‐Claude , Scherman Daniel , Richard Cyrille
Published: March 2012

Single‐walled carbon nanotubes (SWCNTs) containing traces of iron oxide were functionalized by noncovalent lipid‐PEG or covalent carboxylic acid function to supply new efficient MRI contrast agents for in vitro and in vivo applications. Longitudinal (r1) and transversal (r2) water proton relaxivities were measured at 300 MHz, showing a stronger T2 feature as an MRI contrast agent (r2/r1 = 190 for CO2H functionalisation). The r2 relaxivity was demonstrated to be correlated to the presence of iron oxide in the SWNT‐carboxylic function COOH, in comparison to iron‐free ones. Biodistribution studies on mice after a systemic injection showed a negative MRI contrast in liver, suggesting the presence of the nanotubes in this organ until 48 h after i.v. injection. The presence of carbon nanotubes in liver was confirmed after ex vivo carbon extraction. Finally, cytotoxicity studies showed no apparent effect owing to the presence of the carbon nanotubes. The functionalized carbon nanotubes were well tolerated by the animals at the dose of 10 µg g−1 body weight. Copyright © 2012 John Wiley & Sons, Ltd.
Improved quantification in pinhole gated myocardial perfusion SPECT using micro‐CT and ultrasound information
Authors: Goethals Lode R. , Geeter Frank De , Vanhove Chris , Roosens Bram , Devos Hannes , Lahoutte Tony
Published: March 2012

Absolute quantification using single photon emission computed tomography (SPECT) was demonstrated in vitro and in large immobile organs in vivo. To determine the feasibility of in vivo quantification of myocardial perfusion in pinhole gated SPECT, we added an ultrasound derived partial volume correction factor to attenuation and scatter corrections, in combination with gated acquisitions. In nine male Wistar rats, cardiac ultrasound was performed prior to SPECT/CT scans to determine the myocardial wall thickness. SPECT/CT scans were then performed 30 min after injection of 99mTc Tetrofosmin. Animals were killed and six midventricular segments of the left ventricle were excised and counted in a γ‐well counter. Using AMIDE, regional myocardial activity was measured after combined scatter correction (SC) and attenuation correction (AC). These image derived activities were compared with the ex vivo counted activity. To correct for the partial volume effect, a recovery coefficient was determined from a phantom study, to determine the thickness specific partial volume effect. Combined AC and SC led to a significant underestimation of activity compared with ex vivo data (root mean squared error = 0.145 mCi g−1). The recovery coefficient calculated from the phantom study showed a linear relationship with object size from 1 to 6 mm, positioned in the vicinity of the center of the field of view (R2 = 0.98). Correction of nongated SPECT images with a recovery coefficient derived from the diastolic phase results in a global overestimation with root mean squared error = 0.04 mCi g−1. Nongated SPECT images corrected with a recovery coefficient with a weighted average ratio diastolic and systolic phase led to an improved root mean squared error of 0.03 mCi g−1. Combining attenuation correction with scatter correction and a gated partial volume correction yields the best correlation with ex vivo counting (root mean squared error = 0.021 mCi g−1 (systolic) and 0.025 mCi g−1 (diastolic). This study demonstrates a method for improved segmental myocardial perfusion quantification in pinhole gated SPECT, using combined attenuation‐, scatter‐ and ultrasound‐derived partial volume effect corrections. Copyright © 2012 John Wiley & Sons, Ltd.
Visual inputs to the mushroom body calyces of the whirligig beetle Dineutus sublineatus: Modality switching in an insect
Authors: Lin Chan , Strausfeld Nicholas J.
Published: March 2012

The mushroom bodies are prominent lobed centers in the forebrain, or protocerebrum, of most insects. Previous studies on mushroom bodies have focused on higher olfactory processing, including olfactory‐based learning and memory. Anatomical studies provide strong support that in terrestrial insects with mushroom bodies, the primary input region, or calyces, are predominantly supplied by olfactory projection neurons from the antennal lobe glomeruli. In aquatic species that generally lack antennal lobes, the calyces are vestigial or absent. Here we report an exception to this in the whirligig beetle Dineutus sublineatus (Coleoptera: Gyrinidae). This aquatic species lives on water and is equipped with two separate pairs of compound eyes, one pair viewing above and one viewing below the water surface. As in other aquatic insects, the whirligig beetle lacks antennal lobes, but unlike other aquatic insects its mushroom bodies possess robust calyces. Golgi impregnations and fluorescent tracer injections revealed that the calyces are exclusively supplied by visual neurons from the medulla of the dorsal eye optic lobes. No other sensory inputs reach the calyces, thereby showing a complete switch of calyx modality from olfaction to vision. Potential functions of the mushroom bodies of D. sublineatus are discussed in the context of the behavioral ecology of whirligig beetles. J. Comp. Neurol. 520:2562–2574, 2012. © 2012 Wiley Periodicals, Inc.
Postnatal development of chorda tympani axons in the rat nucleus of the solitary tract
Authors: Wang Siting , Corson James , Hill David , Erisir Alev
Published: March 2012

The chorda tympani nerve (CT), one of three nerves that convey gustatory information to the nucleus of the solitary tract (NTS), displays terminal field reorganization after postnatal day 15 in the rat. Aiming to gain insight into mechanisms of this phenomenon, CT axon projection field and terminal morphology in NTS subdivisions were examined using tract tracing, light microscopy, and immunoelectron microscopy at four postnatal ages: P15, P25, P35, and adult. The CT axons that innervated NTS rostrolateral subdivision both in the adult and in P15 rats were morphologically distinct from those that innervated the rostrocentral, gustatory subdivision. In both subdivisions, CT terminals reached morphological maturity before P15. Rostrolateral, but not rostrocentral axons, went through substantial axonal branch elimination after P15. Rostrocentral CT synapses, however, redistribute onto postsynaptic targets in the following weeks. CT terminal preference for GABAergic postsynaptic targets was drastically reduced after P15. Furthermore, CT synapses became a smaller component of the total synaptic input to the rostrocentral NTS after P35. The results underlined that CT axons in rostrocentral and rostrolateral subdivisions represent two distinct populations of CT input, displaying different morphological properties and structural reorganization mechanisms during postnatal development. J. Comp. Neurol., 520:3217–3235, 2012. © 2012 Wiley Periodicals, Inc.
Role of retinal input on the development of striate–extrastriate patterns of connections in the rat
Authors: Laing R.J. , Bock A.S. , Lasiene J. , Olavarria J.F.
Published: March 2012

Previous studies have shown that retinal input plays an important role in the development of interhemispheric callosal connections, but little is known about the role retinal input plays on the development of ipsilateral striate–extrastriate connections and the interplay that might exist between developing ipsilateral and callosal pathways. We analyzed the effects of bilateral enucleation performed at different ages on both the distribution of extrastriate projections originating from restricted loci in medial, acallosal striate cortex, and the overall pattern of callosal connections revealed following multiple tracer injections. As in normal rats, striate–extrastriate projections in rats enucleated at birth consisted of multiple, well‐defined fields that were largely confined to acallosal regions throughout extrastriate cortex. However, these projections were highly irregular and variable, and they tended to occupy correspondingly anomalous and variable acallosal regions. Moreover, area 17, but not area 18a, was smaller in enucleates compared to controls, resulting in an increase in the divergence of striate projections. Anomalies in patterns of striate–extrastriate projections were not observed in rats enucleated at postnatal day (P)6, although the size of area 17 was still reduced in these rats. These results indicate that the critical period during which the eyes influence the development of striate–extrastriate, but not the size of striate cortex, ends by P6. Finally, enucleation did not change the time course and definition of the initial invasion of axons into gray matter, suggesting that highly variable striate projections patterns do not result from anomalous pruning of exuberant distributions of 17–18a fibers in gray matter. J. Comp. Neurol., 520:3256–3276, 2012. © 2012 Wiley Periodicals, Inc.
A stereological study of the numbers of neurons and glia in the primary visual cortex across the lifespan of male and female rhesus monkeys
Authors: Giannaris Eustathia Lela , Rosene Douglas L.
Published: March 2012

Mild age‐related declines in visual function occur in humans and monkeys, independent of ocular pathology, suggesting involvement of central visual pathways (Spear [1993] Vision Res 33:2589–2609). Although many factors might account for this decline, a loss of neurons in primary visual cortex (V1) could be a contributing factor. Previous studies of neuron numbers in V1 reported stability across age, but were limited in the ages and genders studied and sampled only limited parts of V1 or limited cell types, allowing for the possibility of a subtle loss of neurons. We pursued this question in 26 behaviorally tested adult male and female rhesus monkeys ranging from 7.4 to 31.0 years of age by using design‐based stereology to estimate numbers of NeuN‐labeled neurons and thionin‐stained glia within three laminar zones, supragranular (layers II–IVB), granular (IVC), and infragranular (V–VI), across the entirety of V1. There were no significant differences between males and females on any measures, except for total brain weight (P = 0.0038). There was an average of 416,000,000 neurons in V1, but no effect of age on this total or numbers within any laminar zone. Similarly, there was an average of 184,000,000 glia in V1 (44% of the number of neurons), but no effect of age on this total. However, there was a significant age‐related increase in numbers of glia in the infragranular zone, perhaps reflecting a glial response to pathology in myelinated projection fibers. This study provides further evidence that in normal aging neurons are not lost and hence cannot account for age‐related dysfunction. J. Comp. Neurol. 520:3492–3508, 2012. © 2012 Wiley Periodicals, Inc.
Calcium Pumps: Why So Many?
Authors: Brini Marisa , Calì Tito , Ottolini Denis , Carafoli Ernesto
Published: March 2012

Ca2+‐ATPases (pumps) are key to the regulation of Ca2+in eukaryotic cells: nine are known today, belonging to three multigene families. The three endo(sarco)plasmic reticulum (SERCA) and the four plasma membrane (PMCA) pumps have been known for decades, the two Secretory Pathway Ca2+ATPase (SPCA) pumps have only become known recently. The number of pump isoforms is further increased by alternative splicing processes. The three pump types share the basic features of the catalytic mechanism, but differ in a number of properties related to tissue distribution, regulation, and role in the cellular homeostasis of Ca2+. The molecular understanding of the function of all pumps has received great impetus from the solution of the three‐dimensional (3D) structure of one of them, the SERCA pump. This landmark structural advance has been accompanied by the emergence and rapid expansion of the area of pump malfunction. Most of the pump defects described so far are genetic and produce subtler, often tissue and isoform specific, disturbances that affect individual components of the Ca2+‐controlling and/or processing machinery, compellingly indicating a specialized role for each Ca2+pump type and/or isoform. © 2012 American Physiological Society.Compr Physiol2:1045‐1060, 2012.
Strategies for Sustainable Cotton: Comparing Niche with Mainstream Markets
Authors: Illge Lydia , Preuss Lutz
Published: March 2012

This case study examines the strategies by two very different types of textile companies for supplying garments in a more sustainable way: Sweden‐based H&M, a large international firm, and hessnatur of Germany, a small niche player. In particular, the case discusses the strategies the two companies have adopted with regard to managing supplier relations and monitoring adherence to social and environmental standards. The case also discusses the respective implications the two companies' strategies have on society. It aims to stimulate critical thinking regarding the multiple ways in which corporate strategies affect the sustainability footprint of both the company and the wider society in which the company is embedded. The case study should thus be of interest to students of strategic management, but also be useful to those interested in sustainable development or supply chain management. Copyright © 2012 John Wiley & Sons, Ltd and ERP Environment.
Neither P‐gp SNP variants, P‐gp expression nor functional P‐gp activity predicts MDR in a preliminary study of plasma cell myeloma
Authors: Drain Stephen , Catherwood Mark A. , Bjourson Anthony J. , Drake Mary B. , Kettle Paul J. , Alexander H. Denis
Published: March 2012

Introduction:

Multidrug resistance (MDR) mediated by P‐glycoprotein (P‐gp) can compromise the successful treatment of many malignancies including plasma cell myeloma (PCM). However, methods do not yet exist that can accurately determine P‐gp activity in PCM patient samples.

Methods:

In this study, we have utilized new advances in flow cytometric methods to determine the activity of P‐gp in PCM tumor cells. Furthermore, we have used several PCR‐based approaches to perform a pilot study determining the functional impact of ABCB1 SNPs in patients with PCM.

Results:

No associations were seen between P‐gp activity or expression and subgroups of PCM. Similarly, no association was seen between P‐gp expression and SNPs within ABCB1 although a nonsignificant reduction in activity was demonstrated for rs1045642 (P = 0.121).

Conclusions:

We have described a new method for the determination of P‐gp and MRP activity suitable for use in clinical studies and have optimized this method to include a gating strategy, allowing routine use on PCM bone marrow aspirate samples. This is the first patient study to consider the full impact of SNPs within ABCB1 all the way from the genome to the proteome in PCM. The methods described here could also be utilized for future studies of “stem cell like” side populations in PCM that are considered to be drug resistant. Furthermore, minor amendments to these methods will facilitate studies of P‐gp, MRP, and BCRP activity in other haematological malignancies. © 2012 International Clinical Cytometry Society
Expression of coagulation factor XIII subunit A in acute promyelocytic leukemia
Authors: Simon Ágnes , Bagoly Zsuzsa , Hevessy Zsuzsanna , Csáthy László , Katona Éva , Vereb György , Ujfalusi Anikó , Szerafin László , Muszbek László , Kappelmayer János
Published: March 2012

Leukemic cells often express markers, which are not characteristic of their particular cell lineage. In this study, we identified the “A” subunit of coagulation factor XIII (FXIII‐A) in leukemic promyelocytes in de novo AML M3 cases. The cytoplasmic presence of factor XIII‐A has previously been shown only in platelets/megakaryocytes and monocytes/macrophages. Furthermore, more recently we described the presence of FXIII‐A in leukemic lymphoblasts.

We studied 14 patients with this rare type of acute leukemia in a period of 4 years and investigated their bone marrow samples by 3‐color flow cytometry upon diagnosis, mainly focusing on FXIII‐A expression of leukemic cells. We detected FXIII‐A also by ELISA, Western‐blot, and confocal laser scanning microscopy.

This was a homogenous group of AML M3 patients with translocation t(15;17)(q22;q21) detected by fluorescence in situ hybridization (FISH). In 10 out of 14 samples, FXIII‐A was detectable by flow cytometry and was coexpressed with markers characteristic for leukemic promyleocytes (CD45dim/CD13+/CD33+/CD117+/cyMPO+ and HLA‐DR‐/CD34−/CD14−/CD15−). Staining for the markers GPIIb and GPIX were negative, and FXIII‐A was identified in the cytoplasm of the cells by confocal microscopy in a relatively high quantity, as measured by ELISA. By Western blot analysis we could identify FXIII‐A in the native 82 kDa form and in cleaved forms corresponding to cleavage products observed when purified FXIII‐A was treated by human neutrophil elastase.

This novel expression site of FXIII‐A in AML M3 can be considered as a leukemia associated immunophenotype and may have pathophysiological significance. © 2012 International Clinical Cytometry Society
Cyclin D1 inactivation extends proliferation and alters histogenesis in the postnatal mouse retina
Authors: Das Gaurav , Clark Anna M. , Levine Edward M.
Published: March 2012

Background: The cell‐cycle regulator Cyclin D1 is expressed in embryonic retinal progenitor cells (RPCs) and regulates their cell‐cycle rate and neurogenic output. We report here that Cyclin D1 also has important functions in postnatal retinal histogenesis. Results: The initial production of Müller glia and bipolar cells was enhanced in Cyclin D1 knockout (Ccnd1−/−) retinas. Despite a steeper than normal rate of depletion of the RPC population at embryonic ages, postnatal Ccnd1−/− retinas exhibited an extended window of proliferation, neurogenesis, and gliogenesis. Cyclin D3, normally confined to Müller glia, was prematurely expressed in Ccnd1−/− RPCs. However, Cyclin D3 did not compensate for Cyclin D1 in regulating cell‐cycle kinetics or neurogenic output. Conclusions: The data presented in this study along with our previous finding that Cyclin D2 was unable to completely compensate for the absence of Cyclin D1 indicate that Cyclin D1 regulates retinal histogenesis in ways not shared by the other D‐cyclins. Developmental Dynamics 241:941–952, 2012. © 2012 Wiley Periodicals, Inc.