bluuebunny/crossref_metadata_2025 huggingface dataset:
The dynamics of luxury and basic-ness in post-crisis fashion
Authors: Morace Francesco
Published: November 2010

Understanding the current moment of the global fashion system and its potential for future development requires that we retrace the dynamics that have characterized this sector in recent years, pre- and post-crisis. This article traces the dynamics to a new sensibility located between
simplicity and luxury, which is more than just another trend but a new Renaissance. The new sensibility involves the parallel processes of luxury losing its exclusive aura and diffusing into the everyday, and, at the same time, creativity, authenticity and a spirit of craftsmanship emerging
as a form of luxurious basic-ness.
Genome-Wide Association Study Identifies Two Major Loci Affecting Calving Ease and Growth-Related Traits in Cattle
Authors: Pausch Hubert , Flisikowski Krzysztof , Jung Simone , Emmerling Reiner , Edel Christian , Götz Kay-Uwe , Fries Ruedi
Published: November 2010

Identifying quantitative trait loci (QTL) underlying complex, low-heritability traits is notoriously difficult. Prototypical for such traits, calving ease is an important breeding objective of cattle (Bos taurus)-improving programs. To identify QTL underlying calving ease, we performed a genome-wide association study using estimated breeding values (EBVs) as highly heritable phenotypes for paternal calving ease (pCE) and related traits. The massively structured study population consisted of 1800 bulls of the German Fleckvieh (FV) breed. Two pCE-associated regions on bovine chromosomes (BTA) 14 and 21 (P = 5.72 × 10−15 and P = 2.27 × 10−8, respectively) were identified using principal components analysis to correct for population stratification. The two most significantly associated SNPs explain 10% of the EBV variation. Since marker alleles with negative effect on pCE have positive effects on growth-related traits, the QTL may exert their effects on the birthing process through fetal growth traits. The QTL region on BTA14 corresponds to a human chromosome (HSA) region that is associated with growth characteristics. The HSA region corresponding to the BTA21 pCE QTL is maternally imprinted and involved in the Prader–Willi and Angelman syndromes. Resequencing of positional candidate genes on BTA14 revealed a highly significantly (P = 1.96 × 10−14) associated polymorphism ablating a polyadenylation signal of the gene encoding ribosomal protein S20 (RPS20). Our study demonstrates the leverage potential of EBVs in unraveling the genetic architecture of lowly heritable traits.
Influence of Cropping Systems on Soil Aggregate and Weed Seedbank Dynamics During the Organic Transition Period
Authors: Corbin Andrew T. , Thelen Kurt D. , Robertson G. P. , Leep Richard H.
Published: November 2010

Agronomic management during the 3‐yr transition period to organic certification influences soil quality and the weed seedbank. We studied two cropping systems during the transition period and the first certified organic season. A 4‐yr rotation of corn, soybean, wheat/alfalfa, corn (C‐S‐W/A‐C) [Zea maysL.,Glycine max(L.) Merr.,Triticum aestivumL.,Medicago sativaL.], produced under a more complex management that included manure and cover crop residue, was compared to a perennial based corn, alfalfa, alfalfa, corn (C‐A‐A‐C) rotation. We compared soil aggregate size distribution and bulk density after Year 1 and on completion of the transition period. Weed seedbank populations were quantified through two seasons in the greenhouse. Weed surface density and aboveground weed biomass were quantified in the field. Over the course of the study, the percentage of large soil macroaggregates (>2000 μm size class) had 2.7 and 3.4‐fold increase for the C‐A‐A‐C and C‐S‐W/A‐C treatments, respectively. The C‐S‐W/A‐C system generated a 4.5‐fold increase in aggregates of this class when wheat that was interseeded with alfalfa was harvested as forage. Bulk density decreased 14 and 6% for the C‐S‐W/A‐C and the C‐A‐A‐C systems, respectively. There was a 60 to nearly 300% increase in total weed seeds germinated in the greenhouse for the C‐S‐W/A‐C system. This same system had a 60 to more than 500% decreased weed seedbank density in the field. We conclude from this study that either strategy can improve soil quality while the weed seedbank was better managed in the more complicated C‐S‐W/A‐C system.
Physical and Mineral‐Nutrition Properties of Sand‐Based Turfgrass Root Zones Amended with Biochar
Authors: Brockhoff Shane R. , Christians Nick E. , Killorn Randy J. , Horton Robert , Davis Dedrick D.
Published: November 2010

Sand‐based turfgrass root zones have limited nutrient retention and water‐holding capacity. Peat moss often is used to offset these deficiencies, but peat moss decomposes. Biochar is a co‐product of several biofuel production processes used to produce bio‐oil. Biochar is stable and could have similar water and nutrient retention impacts as peat moss when mixed in sand‐based turfgrass root zones. The objective of this research was to evaluate the efficacy of biochar as a sand‐based root zone amendment. Water retention, water infiltration, creeping bentgrass (Agrostis stolonifera L.) rooting depth, and nutrient evaluation experiments were conducted on six sand and biochar root zone mixtures. At field capacity, sand‐based media containing 25% (v/v) biochar retained 260 and 370% more water compared to media containing 5% biochar and a pure sand control, respectively. Saturated hydraulic conductivity (Ksat) of the root zones decreased as biochar concentrations increased. The rooting depth of bentgrass was reduced up to 46% at biochar concentrations >10%. Extracted pore water electrical conductivity and dissolved total organic carbon increased as biochar concentrations increased. Nitrogen leaching was reduced as biochar concentrations increased. According to the results, biochar may improve water storage, reduce overall water use, and decrease N fertilizer applications in sand‐based turfgrass ecosystems.
The effect of breeding region and year on milk traits of simmental bull dams
Authors: Pantelic V. , Aleksic S. , Stojic P. , Djurdjevic R. , Samolovac Lj. , Jankovic D. , Niksic D.
Published: November 2010

Cows which represent top of the genetic value of the population in regard to
their traits are chosen for bull dams. Selection is based on origin,
production performance (quantity of milk, milk fat and protein content),
milking/dairy traits, reproductive indicators, exterior and linear type
scores. This study included 292 cows of Simmental breed selected for bull
dams on the territory of Republic of Serbia during one year. Selection of
cows for herd of bull dams was done after finalized first and subsequent
lactation. In this study, the effect of region and year of calving on milk
traits is presented. Applying the method of least squares average value of
milk production was obtained - 5.754,49 kg, milk fat content - 3,98% and
quantity of milk fat - 230,24 kg. Regions had statistically highly
significant effect (P<0,01) on all investigated milk traits. Year of calving
showed no statistically significant effect on milk yield, yield of milk fat
and content of milk fat (P>0,05).
Fibrofatty Changes in Failed Pediatric Cardiac Allografts
Authors: Sacks jeffrey H. , Mahle William T. , Abramowsky Carlos R. , Steelman Charlotte K. , Kanter Kirk R. , Vincent Robert N. , Berg Alexandria , Shehata Bahig M.
Published: November 2010

The pathogenesis of right ventricular fibrofatty changes can be broadly divided into genetic or acquired. The genetic cause is termed arrhythmogenic right ventricular dysplasia, an inherited cardiomyopathy characterized by fibrofatty replacement of the right ventricular myocardium, and represents an underdiagnosed cardiac entity leading to syncope, recurrent ventricular tachycardias, heart failure, and sudden death. Our study demonstrates that fibrofatty changes can also be seen in pediatric cardiac allografts. Conversely, fat replacement without fibrosis may be seen secondary to infectious myocarditis, chronic inflammation, and ischemia and as part of the aging process. We examined 29 failed cardiac allografts to identify the etiology of graft failure. In this study, 4 patients (13%) had severe right ventricular fibrofatty changes, and when compared with control patients, those with fibrofatty changes had a shorter interval from transplant to graft failure, 2.75 years vs 5.45 years ( P = 0.029). Neither body mass index nor other physiologic parameters found on electrocardiography, echocardiography, or cardiac catherization were different between groups. Furthermore, arrhythmias indicative of arrhythmogenic right ventricular dysplasia were not observed in the study group. This study suggests the fibrofatty infiltration in cardiac allografts is a clinically different entity from arrhythmogenic right ventricular dysplasia and has an unknown etiology. Our study findings suggest that identifying fibrofatty infiltrates in cardiac transplant patients during routine right ventricular biopsy can be a predictive factor for shortened life of the pediatric cardiac allograft.
Cloud-to-ground lightning over Mexico and adjacent oceanic regions: a preliminary climatology using the WWLLN dataset
Authors: Kucieńska B. , Raga G. B. , Rodríguez O.
Published: November 2010

Abstract. This work constitutes the first climatological study of lightning over Mexico and adjacent oceanic areas for the period 2005–2009. Spatial and temporal distributions of cloud to ground lightning are presented and the processes that contribute to the lightning variability are analysed. The data are retrieved from the World Wide Lightning Location Network (WWLLN) dataset. The current WWLL network includes 40 stations which cover much of the globe and detect very low frequency radiation ("spherics") associated with lightning. The spatial distribution of the average yearly lightning over the continental region of Mexico shows the influence of orographic forcing in producing convective clouds with high lightning activity. However, a very high number of strikes is also observed in the States of Tabasco and Campeche, which are low-lying areas. This maximum is related to the climatological maximum of precipitation for the country and it may be associated with a region of persistent low-level convergence and convection in the southern portion of the Gulf of Mexico. The maps of correlation between rainfall and lightning provide insight into the microphysical processes occurring within the clouds. The maritime clouds close to the coastline exhibit similar properties to continental clouds as they produce very high lightning activity. The seasonal cycle of lightning registered by WWLLN is consistent with the LIS/OTD dataset for the selected regions. In terms of the annual distribution of cloud-to-ground strikes, July, August and September exhibit the highest number of strikes over continental Mexico. The diurnal cycle indicates that the maximum number of strikes over the continent is observed between 6 and 9 p.m. LT. The surrounding oceanic regions were subdivided into four distinct sectors: Gulf of Mexico, Caribbean, Sub-tropical Pacific and Tropical Pacific. The Gulf of Mexico has the broadest seasonal distribution, since during winter lightning associated with mid-latitude systems also affects the region. The diurnal distribution of lightning for the Gulf of Mexico exhibits the highest number of strokes at 9 a.m. The Caribbean seasonal distribution is slightly biased towards early fall, with a clear maximum observed during October. The diurnal distribution of lightning over the Caribbean is quite uniform with a slight increase near midnight. The Subtropical Pacific has the narrowest seasonal distribution, associated with the convection observed during the "North American Monsoon", with the maximum number of strikes during August and September. In contrast, the Tropical Pacific has a broader seasonal cycle, associated with convection in the Inter-Tropical Convergence Zone (ITCZ), starting in May and lasting till October. In both adjacent Pacific regions, the strikes present a maximum in the early morning, the time of the highest frequency of land breeze.
Planning for Chronic Disease Medications in Disaster: Perspectives From Patients, Physicians, Pharmacists, and Insurers
Authors: Carameli Kelley A. , Eisenman David P. , Blevins Joy , d'Angona Brian , Glik Deborah C.
Published: November 2010

Background

Recent US disasters highlight the current imbalance between the high proportion of chronically ill Americans who depend on prescription medications and their lack of medication reserves for disaster preparedness. We examined barriers that Los Angeles County residents with chronic illness experience within the prescription drug procurement system to achieve recommended medication reserves.

Methods

A mixed methods design included evaluation of insurance pharmacy benefits, focus group interviews with patients, and key informant interviews with physicians, pharmacists, and insurers.

Results and Discussion

Most prescriptions are dispensed as 30-day units through retail pharmacies with refills available after 75% of use, leaving a monthly medication reserve of 7 days. For patients to acquire 14- to 30-day disaster medication reserves, health professionals interviewed supported 60- to 100-day dispensing units. Barriers included restrictive insurance benefits, patients’ resistance to mail order, and higher copay-ments. Physicians, pharmacists, and insurers also varied widely in their preparedness planning and collective mutual-aid plans, and most believed pharmacists had the primary responsibility for patients’ medication continuity during a disaster.

Conclusions

To strengthen prescription drug continuity in disasters, recommendations include the following: (1) creating flexible drug-dispensing policies to help patients build reserves, (2) training professionals to inform patients about disaster planning, and (3) building collaborative partnerships among system stakeholders. (Disaster Med Public Health Preparedness. 2013;7:257-265)
New Cellular Metals with Enhanced Energy Absorption: Wire‐Woven Bulk Kagome (WBK)‐Metal Hollow Sphere (MHS) Hybrids
Authors: Li Ming‐Zhen , Stephani Günter , Kang Ki‐Ju
Published: November 2010

Two types of new cellular metals are fabricated by assembling layer by layer helically‐formed wires with metal hollow sphere (MHS) arrays. In the finished configuration, the MHSs are located in small tetrahedrons or octahedrons of the inner space of a wire‐woven bulk Kagome (WBK) structure. Compression tests reveal excellent energy absorption, which is attributed to combination of suppression of strut buckling in the WBK and moving plastic hinge occurring in the MHSs. The WBK‐MHS hybrids outperform competitors in deformation energy absorption.
N‐Doped CsTaWO6 as a New Photocatalyst for Hydrogen Production from Water Splitting Under Solar Irradiation
Authors: Mukherji Aniruddh , Marschall Roland , Tanksale Akshat , Sun Chenghua , Smith Sean C. , Lu Gao Qing , Wang Lianzhou
Published: November 2010

Photocatalysts for efficient solar hydrogen production are highly sought after. Here a new type of nitrogen‐doped tantalum tungstenate (CsTaWO6) material, which demonstrates excellent visible light absorption and improved photocatalytic activity, is demonstrated. X‐ray diffraction (XRD) patterns reveal that the defect pyrochlore‐type structure of CsTaWO6 remained intact upon nitrogen doping. UV‐vis spectra indicate that nitrogen doping in the compound results in a red‐shift of the absorption edge from 358 nm to 580 nm, thus offering significantly increased visible light absorption. X‐ray photoelectron spectroscopy (XPS) further indicates that [Ta/W]–N bonds were formed by inducing nitrogen to replace a small amount of oxygen in the material, resulting in a compound of CsTaWO6‐xNx. The explanation of the experimental results is supported by density functional theory calculations. The density of states (DOS) and the projected DOS after substitutional doping of nitrogen in CsTaWO6 indicated that N‐doping reduces the bandgap significantly from 3.8 to 2.3 eV due to N 2p and O 2p orbital mixing. The role of the new N 2p states is also investigated by studying the production of the •OH radicals in the visible light region (>420 nm). In CsTaWO6‐xNx, the N 2p orbitals are the main contributors to the top of the valence band, causing bandgap narrowing while the bottom of conduction band, due to Ta 4d orbitals, remains almost unchanged. Compared with its undoped counterpart, nitrogen‐doped CsTaWO6‐xNx exhibits a nearly 100% increase in solar hydrogen production efficiency.
Toward a Continuous‐Flow Synthesis of Boscalid®
Authors: Glasnov Toma N. , Kappe C. Oliver
Published: November 2010

A two‐step continuous‐flow protocol for the synthesis of 2‐amino‐4′‐chlorobiphenyl, a key intermediate for the industrial preparation of the fungicide Boscalid® is described. Initial tetrakis(triphenylphosphine)palladium‐catalyzed high‐temperature Suzuki–Miyaura cross‐coupling of 1‐chloro‐2‐nitrobenzene with 4‐chlorophenylboronic acid in a microtubular flow reactor at 160 °C using the tert‐butanol/water/potassium tert‐butoxide solvent/base system provides 4′‐chloro‐2‐nitrobiphenyl in high yield. After in‐line scavenging of palladium metal with the aid of a thiourea‐based resin, subsequent heterogeneous catalytic hydrogenation is performed over platinum‐on‐charcoal in a dedicated continuous‐flow hydrogenation device. The overall two‐step homogeneous/heterogeneous catalytic process can be performed in a single operation providing the desired 2‐amino‐4′‐chlorobiphenyl in good overall yield and high selectivity.
Triphenylantimony(V) o‐amidophenolates with unsymmetrical N‐aryl group for a reversible dioxygen binding
Authors: Poddel'sky Andrey I. , Kurskii Yury A. , Piskunov Alexandr V. , Somov Nikolay V. , Cherkasov Vladimir K. , Abakumov Gleb A.
Published: November 2010

New triphenylantimony(V) o‐amidophenolates (AP‐Me,Et)SbPh3 (1) and (AP‐Me,iPr)SbPh3 (2) with unsymmetrically substituted N‐aryl groups and (AP‐Et,Et)SbPh3 (3) with symmetrical N‐aryl group {AP‐R1,R2 is 4,6‐di‐tert‐butyl‐N‐[2‐alkyl(R1),6‐alkyl(R2)‐phenyl]‐o‐amidophenolate dianion} were synthesized and characterized in detail. Complexes were examined for dioxygen activity. The unsymmetrical complexes 1 and 2 were found to form different geometrical isomers (A and B) of spiroendoperoxides [L‐R1,R2(O2)]SbPh3 (4 and 5, respectively) with different dispositions of peroxide group and N‐aryl fragment (methyl and peroxide group are on the same side of the molecule in the less shielded isomer A, and on different sides in the more hindered isomer B). The isomer A prevails over isomer B, reflecting the possibility of steric control on the dioxygen‐binding reaction. Complex 3, where R1 = R2 = Et, formed the isomers 6A and 6B as 50:50. The ratio 4A:4B was 60:40 (for methyl‐ethyl containing complex 4) and it increased up to 80:20 for methyl‐isopropyl‐containing 5. The molecular structure of isomers 4A and 4B was confirmed by X‐ray analysis. Copyright © 2010 John Wiley & Sons, Ltd.
In situ polymerization of aniline on acrylamide grafted cotton
Authors: Li Rong , Liu Gaofeng , Gu Feng , Wang Zheng , Song Yang , Wang Jianqing
Published: November 2010

In this article, polyaniline (PANI)/cotton composite were prepared by in situ polymerization on the grafted cotton. First, acrylamide was grafted onto cotton cellulose using a radical graft polymerization process and some influencing factors were studied. Then polyaniline/cotton conductive composite fabrics were prepared by chemical in situ polymerization on the grafted cotton. The influences of the concentration of ammonium persulfate, aniline, hydrochloric acid, and the reaction time to the conductivity and K/S of composite fabric were studied. By contrasting, graft brought on an improvement of about one order of magnitude to the conductivity of composite fabric. The strength, TG, FTIR‐ATR, and SEM of prepared fabric were measured. The thermal stability and tear strength of composite fabric reduced, whereas PANI exhibited a rough but uniform, coherent PANI coating on surface of cotton fiber. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Proton conducting polymer blends from poly(2,5‐benzimidazole) and poly(2‐acrylamido‐2‐methyl‐1‐propanesulfonic acid)
Authors: Sen Unal , Acar Oktay , Bozkurt Ayhan , Ata Ali
Published: November 2010

Proton conducting polymer electrolyte membranes were produced by blending of poly(2,5‐benzimidazole) (ABPBI) and poly(2‐acrylamido‐2‐methyl‐1‐propanesulfonic acid) (PAMPS) at several stoichiometric ratios with respect to polymer repeating units. The membranes were characterized by using Fourier transform infrared spectroscopy for interpolymer interactions and scanning electron microscope for surface morphology. Thermal stability of the materials was investigated by thermogravimetric analysis. Glass transition temperatures of the samples were measured via differential scanning calorimetry. The spectroscopic measurements and water uptake studies indicate a complexation between ABPBI and PAMPS that inhibited polymer exclusion up on swelling in excess water. Proton conductivities of the anhydrous and humidified samples were measured using impedance spectroscopy. The proton conductivity of the humidified ABPBI:PAMPS (1 : 2) blend showed a proton conductivity of 0.1 S/cm, which is very close to Nafion 117, at 20°C at 50% relative humidity. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Nafion®—titania nanocomposite proton exchange membranes
Authors: Ye Gongbo , Li Ke , Xiao Chuan , Chen Wei , Zhang Haining , Pan Mu
Published: November 2010

Proton exchange membranes consisting of Nafion® and crystallized titania nanoparticles have been developed to improve water‐retention and proton conductivity at elevated temperature and low relative humidity. The anatase‐type titania nanoparticles were synthesized in situ in Nafion solution through sol–gel process and the size of the formed titiania nanoparticles is in the range of 3–6 nm. The formed nanoparticles are well‐dispersed in Nafion solution at the titania concentration of 5 wt %. The glass transition temperature of the formed Nafion‐titania composite membrane is about 20oC higher than that of plain Nafion membrane. At elevated temperature (above 100°C), the Nafion‐titania nanocomposite membrane shows higher water uptake ability and improved proton conductivity compared to pure Nafion membrane. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
The Physical Chemistry of Stressed Solids
Authors: Cahn John W.
Published: November 2010

The ability to resist shear is a defining characteristic of a solid, and distinguishes it from liquids and gases. Stress is one of the major additional features, in addition to periodicity and anisotropy, in the physical chemistry of solids. Diffusion, phase changes, and reactions alter the state of stress, and this in turn affects the course of the reactions. The stressed state can be an equilibrium state under the constraints of the available mechanisms. The current view of the physical chemistry of stressed solids will be surveyed with emphasis on the many new concepts about equilibria and how stresses evolve and influence reaction paths and mechanisms.
Neue Werkstoffe durch Gefügedesign — Chancen und Grenzen —
Authors: Petzow G.
Published: November 2010

The close correlation between microstructure and properties is the basis for well‐defined development of advanced materials. The higher the requirements on a material are the more exacting are the demands on the microstructure, i.e. the more precise the microstructure must be tuned. The knowledge of the microstructure and its property interaction is the focus of interest of materials science. The advanced ceramics are an example for a directed microstructural optimization being an important prerequisite for technological application. The utilization of scientific knowledge of the microstructure of this class of materials still being at the developmental stage resulted in a considerable improvement of their properties. This is true particularly for the mechanical properties which can be improved considerably by toughening concepts such as transformation toughening.
Anisotropy of 2‐Norbornyl Radical Reorientational Dynamics in the Plastic Phase of Norbornene as Determined by ALC‐μSR
Authors: Roduner Emil , Reid Ivan D. , Riccò Mauro , Renzi Roberto De
Published: November 2010

Avoided level crossing muon spin resonance effects are observed with polycrystalline norbornene in its plastic phase and analysed in terms of axial hyperfine anisotropy. The results agree with those of previous single crystal measurements. It is shown that the technique is sensitive to the detection of small anisotropies, and that it is ideally suited for the study of reorientational dynamics in polycrystalline or amorphous environments.
Anomalous Transport on Random Fractal Structures: Stretched Gaussians, Power‐Laws and Logarithmic Time Dependences
Authors: Roman H. Eduardo , Bunde Armin , Havlin Shlomo
Published: November 2010

We study diffusion of Brownian particles on random fractal structures, self‐avoiding random walks and percolation clusters at criticality, which serve as model systems for polymers in a good solvent and random two‐component mixtures, respectively. Using numerical simulations and scaling arguments we find that the distribution function P(r, t) of the particles is a stretched Gaussian and scales as log[P(r, t)/P(r, 0)] ∼ —[r/R(t)]u, where R(t) ∼t1/dw is the root‐mean‐square displacement, u = dw/(dw‐1), and dw = 2df for self‐avoiding walks and dw = 3df/2 for percolation; df is the fractal dimension of the structure. In the presence of an external constant bias field, diffusion is drastically reduced and R(t) ∼ logt evolves logarithmically in time, in exactly the same way in both fractal structures.
Solid Electrolytes
Authors: West A. R.
Published: November 2010

A review of recent progress in the science and applications of solid electrolytes is given. This includes the development of new materials, both as ionic and mixed ionic/electronic conductors, improved understanding of conduction mechanisms and the factors that led to high ionic conductivity in solids and increased applications in batteries, fuel cells, sensors and electrochromic devices.
Mobility in Single Crystals Studied by Optical Nuclear Polarization
Authors: Allgeier J. , Buntkowsky G. , Hentrich S. , Nack M. , Vieth H.‐M.
Published: November 2010

By optical excitation of molecular triplet states along with selective population of their spin sublevels nuclear spin polarization can be generated up to a level far above the Boltzmann equilibrium. This effect known as Optical Nuclear Polarization (ONP) has been applied for the investigation of dynamical processes in solid state matrices in the following three ways: (i) The efficiency of the ONP process and its dependency on an external magnetic field is affected by the fluctuation of local fields which is correlated to molecular motions. (ii) By pulsed irradiation of light and radio‐frequencies one can achieve a temporal resolution of the polarization process; in this way the time evolution of the spin order of the molecular states involved in the optical excitation cycle can be mapped out. (iii) The high nuclear polarization makes time resolved NMR measurements on solid state systems feasible which cannot be studied by conventional techniques because of insufficient sensitivity, e.g. guest molecules in low concentrations or isotopes with small natural abundance. The three methods, which cover together a time range between 10−12 and 103 seconds are illustrated by experiments on various organic crystals.
Deuteron NMR Relaxation Studies of Combined Main‐Chain/Side‐Chain Polymers in the Liquid Crystalline and Glassy State
Authors: Kohlhammer Klaus , Kothe Gerd , Reck Bernd , Ringsdorf Helmut
Published: November 2010

Combined main‐chain/side‐chain polymers have been studied by deuteron NMR relaxation techniques. Analysis of the various experiments, employing an appropriate relaxation model, provides detailed information about the molecular organization of these systems. From the dynamic point of view, the primary result is the detection and characterization of the dominant molecular motions above and below the glass transition. Molecular order is characterized by unusually high order parameters of the main‐chain mesogens, exceeding those of the side groups considerably. In addition to molecular biaxiality, observed in all mesophases, there is evidence for phase biaxiality in the smectic A phase.
Mechanism of the Conductivity in Spinel Type Fast Lithium Ion Conductors Li2MIICl4 — Neutron Diffraction of Li1.6Cu0.4MnCl4 and Li0.6Na1.4MnCl4
Authors: Lutz H. D. , Kuske P. , Pfitzner A.
Published: November 2010

Neutron diffraction studies of the spinel type quaternary chlorides Li1.6Cu0.4MnCl4 and Li0.6Na1.4MnCl4 at elevated temperatures are presented. The final R1 were 4.05 (100°C) and 9.12% (410°C), respectively. The cation distribution, i.e., (Li0.6Cu0.4)[LiMn]Cl4 and (Li0.1)[Li0.5Na1.4Mn]Cl4, and the great Frenkel disorder of the tetrahedrally coordinated ions to the interstitial octahedral 16c sites are discussed with respect to the mechanism of the conduction process in these fast lithium ion conductors.
Two‐dimensional Chemical Compounds on Single Crystal Surfaces
Authors: Uebing C. , Viefhaus H. , Grabke H. J.
Published: November 2010

Surface segregation phenomena were studied on (100) oriented single crystal surfaces of Fe—15% Cr—C/N, Fe—3% V—C/N and Fe—3% Si—0.04% V—C alloys by Auger electron spectroscopy (AES) and low energy electron diffraction (LEED). Upon cosegregation of the constituent components the two‐dimensional surface compounds CrN, CrC, V(C, N) and VC are formed at elevated temperatures. — The surface compounds are epitaxially arranged on the substrate surface. Their structures correspond to the (100) planes of the three‐dimensional bulk precipitates CrN, V(C, N) and VC with rocksalt structure and of a hypothetical cubic CrC. — The thermodynamic stability ranges of surface compounds are discussed in relation to the stability of the bulk precipitates. Phase equilibria between two‐and three‐dimensional phases are interpreted applying a generalized phase rule.
Determination of acetamiprid residues in zucchini grown under greenhouse conditions: application to behavioral dynamics
Authors: Park Ji‐Yeon , Choi Jeong‐Heui , Kim Bo‐Mee , Park Jong‐Hyouk , Cho Soon‐Kil , Ghafar M. W. , Abd El‐Aty A. M. , Shim Jae‐Han
Published: November 2010

A simple analytical method was developed for the determination of acetamiprid residues in zucchini and zucchini leaves grown under greenhouse conditions using liquid chromatography. Residues were confirmed via tandem mass spectrometry in positive‐ion electrospray ionization mode. The calibration curves were linear with correlation coefficients in excess of 0.999. The limits of detection and limits of quantification were 0.01 and 0.03 µg/g and 0.02 and 0.06 µg/g, for the zucchini and zucchini leaves, respectively. For validation purposes, recoveries studies were carried out at low and high levels, yielding recovery rates ranged from 85.7 to 92.2% in zucchini and from 90.5 to 101.9% in zucchini leaves, with a relative standard deviation of <12%. The results demonstrated that the pattern of acetamiprid dissipation followed pseudo first‐order kinetics with a half‐life of 1.9 and 2.5 days, respectively. The residues in zucchini leaves were substantially higher than in the zucchini plant itself. No residues were detected at 7 days post‐application. The results of this study suggest that acetamiprid is acceptable for application in/on zucchini under the recommended dosage conditions.
A Fluorescent sp2‐Iminosugar With Pharmacological Chaperone Activity for Gaucher Disease: Synthesis and Intracellular Distribution Studies
Authors: Luan Zhuo , Higaki Katsumi , Aguilar‐Moncayo Matilde , Li Linjing , Ninomiya Haruaki , Nanba Eiji , Ohno Kousaku , García‐Moreno M. Isabel , Ortiz Mellet Carmen , García Fernández José M. , Suzuki Yoshiyuki
Published: November 2010

Gaucher disease (GD) is the most prevalent lysosomal‐storage disorder, it is caused by mutations of acid β‐glucosidase (β‐glucocerebrosidase; β‐Glu). Recently, we found that bicyclic nojirimycin (NJ) derivatives of the sp2‐iminosugar type, including the 6‐thio‐N′‐octyl‐(5N,6S)‐octyliminomethylidene derivative (6S‐NOI‐NJ), behaved as very selective competitive inhibitors of the lysosomal β‐Glu and exhibited remarkable chaperone activities for several GD mutations. To obtain information about the cellular uptake pathway and intracellular distribution of this family of chaperones, we have synthesized a fluorescent analogue that maintains the fused piperidine–thiazolidine bicyclic skeleton and incorporates a dansyl group in the N′‐substituent, namely 6‐thio‐(5N,6S)‐[4‐(N′‐dansylamino)butyliminomethylidene]nojirimycin (6S‐NDI‐NJ). This structural modification does not significantly modify the biological activity of the glycomimetic as a chemical chaperone. Our study showed that 6S‐NDI‐NJ is mainly located in lysosome‐related organelles in both normal and GD fibroblasts, and the fluorescent intensity of 6S‐NDI‐NJ in the lysosome is related to the β‐Glu concentration level. 6S‐NDI‐NJ also can enter cultured neuronal cells and act as a chaperone. Competitive inhibition studies of 6S‐NDI‐NJ uptake in fibroblasts showed that high concentrations of D‐glucose have no effect on chaperone internalization, suggesting that it enters the cells through glucose‐transporter‐independent mechanisms.
Catalysis and Mechanistic Insights into Sirtuin Activation
Authors: Dittenhafer‐Reed Kristin E. , Feldman Jessica L. , Denu John M.
Published: November 2010

SIRT1 is a member of the Sir2 family of NAD+‐dependent protein deacetylases. The central role of SIRT1 in multiple metabolic and age‐related pathways has pushed SIRT1 to the forefront to discover small‐molecule activators. Promising compounds, including resveratrol and SRT1720 have been reported, however, whether these compounds are direct activators and the mechanism by which they activate remains poorly defined. This review examines the current debate surrounding purported activators, and will focus on the assays used in screening compounds, sirtuin catalysis, and the mechanistic basis for their actions. We discuss the potential pathways of SIRT1 activation that could be exploited for the development of novel therapeutics for treating type II diabetes, neurodegeneration, and diseases associated with aging.
Full Theoretical Cycle for both Ethene and Propene Formation during Methanol‐to‐Olefin Conversion in H‐ZSM‐5
Authors: Lesthaeghe David , Van der Mynsbrugge Jeroen , Vandichel Matthias , Waroquier Michel , Van Speybroeck Veronique
Published: November 2010

The methanol‐to‐olefin (MTO) process, catalyzed by acidic zeolites such as H‐ZSM‐5, provides an increasingly important alternative to the production of light olefins from crude oil. However, the various mechanistic proposals for methanol‐to‐olefin conversion have been strongly disputed for the past several decades. This work provides theoretical evidence that the experimentally suggested ‘alkene cycle’, part of a co‐catalytic hydrocarbon pool, offers a viable path to the production of both propene and ethene, in stark contrast to the often‐ proposed direct mechanisms. This specific proposal hinges on repeated methylation reactions of alkenes, starting from propene, which occur easily within the zeolite environment. Subsequent cracking steps regenerate the original propene molecule, while also forming new propene and ethene molecules as primary products. Because the host framework stabilizes intermediate carbenium ions, isomerization and deprotonation reactions are extremely fast. Combined with earlier joint experimental and theoretical work on polymethylbenzenes as active hydrocarbon pool species, it is clear that, in zeolite H‐ZSM‐5, multiple parallel and interlinked routes operate on a competitive basis.
A Piggyback Ride for Transition Metals: Encapsulation of Exohedral Metallofullerenes in Carbon Nanotubes
Authors: Chamberlain Thomas W. , Champness Neil R. , Schröder Martin , Khlobystov Andrei N.
Published: November 2010

We have developed a method that enables the efficient insertion of transition‐metal atoms and their small clusters into carbon nanotubes. As a model system, Os complexes attached to the exterior of fullerene C60 (exohedral metallofullerenes) were shown to be dragged into the nanotube spontaneously and irreversibly due to strong van der Waals interactions, specific to fullerenes and carbon nanotubes. The size of the metal‐containing groups attached to C60 was shown to be critical for successful insertion, as functional groups too bulky to enter the nanotube were stripped off the fullerene during the encapsulation process. Once inside the nanotube, Os atoms catalyse polymerisation and decomposition of fullerene cages, which is related to a much higher catalytic activity of metal atoms situated on the surface of the fullerene cage, as compared to metal atoms in endohedral fullerenes, such as M@C82. Thus, exohedral metallofullerenes show promise for applications in catalysis in carbon “nano” test tubes.
Effect of tube diameter on two‐phase flow patterns in mini tubes
Authors: Venkatesan M. , Das Sarit K. , Balakrishnan A. R.
Published: November 2010

The effect of tube diameter on two‐phase flow patterns was investigated in circular tubes with inner diameters of 0.6, 1.2, 1.7, 2.6, and 3.4 mm using air and water. The gas and liquid superficial velocity ranges were 0.01–50 and 0.01–3 m/s, respectively. The gas and liquid flow rates were measured and the two‐phase flow pattern images were recorded using high‐speed CMOS camera. The flow patterns observed were dispersed bubbly, bubbly, slug, slug‐annular, wavy‐annular, stratified, and annular flows. These flow patterns were not observed in all the test diameters, but were found to be unique to particular tube diameters, confirming the effect of tube diameter on the flow pattern. The data obtained were compared to existing experimental data and flow regime transition maps which show generally reasonable overall agreement at the larger diameters, but significant differences were observed with the smaller diameter tubes.
Biomimetic gradient hydrogels for tissue engineering
Authors: Sant Shilpa , Hancock Matthew J. , Donnelly Joseph P. , Iyer Dharini , Khademhosseini Ali
Published: November 2010

During tissue morphogenesis and homeostasis, cells experience various signals in their environments, including gradients of physical and chemical cues. Spatial and temporal gradients regulate various cell behaviours such as proliferation, migration, and differentiation during development, inflammation, wound healing, and cancer. One of the goals of functional tissue engineering is to create microenvironments that mimic the cellular and tissue complexity found in vivo by incorporating physical, chemical, temporal, and spatial gradients within engineered three‐dimensional (3D) scaffolds. Hydrogels are ideal materials for 3D tissue scaffolds that mimic the extracellular matrix (ECM). Various techniques from material science, microscale engineering, and microfluidics are used to synthesise biomimetic hydrogels with encapsulated cells and tailored microenvironments. In particular, a host of methods exist to incorporate micrometer to centimetre scale chemical and physical gradients within hydrogels to mimic the cellular cues found in vivo. In this review, we draw on specific biological examples to motivate hydrogel gradients as tools for studying cell–material interactions. We provide a brief overview of techniques to generate gradient hydrogels and showcase their use to study particular cell behaviours in two‐dimensional (2D) and 3D environments. We conclude by summarizing the current and future trends in gradient hydrogels and cell–material interactions in context with the long‐term goals of tissue engineering.
Stokesian dynamics and the settling behaviour of particle–fibre‐mixtures
Authors: Feist M. , Keller F. , Nirschl H. , Dörfler W.
Published: November 2010

For many industrial applications, like purification of waste water, some filtration processes and the paper recycling process, knowledge about the sedimentation and separation behaviour of fibres and particles is required. Experiments with many particles or fibres predict a great influence between them. From literature it is well known that the sedimentation behaviour is influenced by parameters like the concentration of the suspension, the physico–chemical interactions, etc. Nearly all reported experiments were performed with pure particle or pure fibre suspensions. The core difference between those suspensions is the shape of the fibres or long bodies which causes an orientation and agglomeration during the sedimentation. Hardly any experiments are reported with suspensions where particles and fibres settle together in the same suspension. To calculate such a sedimentation process with all the particle interactions one needs a suitable mathematical model, because direct numerical methods would take to much time. Therefore, in this paper we will reformulate the model of the Stokesian Dynamics Method. We will focus on the underlying assumptions and their effects and show that our simulations of some particles are in good agreement to the literature. Due to the validity of this method for spheres only, we approximate a rigid fibre as a chain of spheres and also give a comparison of this approximation. Finally we investigate the sedimentation behaviour of particle–fibre suspensions to show the influence of the density ratio between the fibres and particles and the influence of the length of the fibres on the separation behaviour.
Application of the central composite design and response surface methodology to remove arsenic from industrial phosphorus by oxidation
Authors: Yongsheng Ren , Jun Li , Xiaoxiao Duan
Published: November 2010

Oxidation is applied to remove arsenic from industrial phosphorus, and nitric acid is chosen as the main oxidant and molysite (Fe3+) as the oxidation intensifier to oxidise arsenic selectively prior to oxidise phosphorus. The central composite design (CCD) and response surface methodology (RSM) are applied to this purification process. The factors considered for experimental design are the concentration of nitric acid, stirring rate, the mass ratio of iron to arsenic, and the volume ratio of nitric acid to phosphorus. The significant factors are optimised using a 24 full factorial CCD of orthogonal type. The quadratic models between the responses and the independent parameters are built. The response surface models are tested with analysis of variance (ANOVA) and the optimal conditions are found: 12.5% for the concentration of nitric acid, 80 for the mass ratio of iron to arsenic, 319 rpm for stirring rate, and 3.14 for the volume ratio of nitric acid to phosphorus with the prediction of 99.9996% of the arsenic removal ratio (ARR) and 74.64% of phosphorus yield (PY). The experimental results indicate that oxidation could remove almost all arsenic from industrial phosphorus, which could prepare low arsenic phosphoric products.

L'oxydation est utilisée pour éliminer l'arsenic des phosphores industriels. On choisit l'acide nitrique comme oxydant principal et le molysite (Fe3+) comme promoteur d'oxydation afin d'oxyder sélectivement l'arsenic avant d'oxyder le phosphore. Le plan central composite (PCC) et la méthode de surface de réponse (MSP) sont appliqués à ce processus de purification. Les facteurs pris en compte dans le plan expérimental sont la concentration d'acide nitrique, la vitesse d'agitation, le rapport de masse du fer par rapport à l'arsenic et le rapport de volume entre l'acide nitrique et le phosphore. Les facteurs importants sont optimisés grâce à un plan central composite de type orthogonal à 24 facteurs entiers. Les modèles quadratiques sont établis entre les réponses et les paramètres indépendants. Les modèles de surface de réponse ont été évalués grâce à l'analyse de la variance (ANOVA) et les conditions optimales suivantes ont été trouvées: une concentration d'acide nitrique de 12,5%, un rapport de masse du fer par rapport à l'arsenic de 80, une vitesse d'agitation de 319 rotations par minute et un rapport de volume de l'acide nitrique par rapport au phosphore de 3,14 avec un taux d'élimination de l'arsenic (TEA) estimé à 99,9996% et une production de phosphore de 74,64% (PP). Les résultats expérimentaux indiquent que l'oxydation peut éliminer presque tout l'arsenic contenu dans les phosphores industriels, ce qui permettrait d'obtenir des produits phosphoriques pauvres en arsenic. © 2010 Canadian Society for Chemical Engineering
Glomerular Filtration
Authors: Maddox David A. , Deen William M. , Brenner Barry M.
Published: November 2010

The sections in this article are:

Glomerular Filtration of Water

Composition of the Glomerular Ultrafiltrate

Determinants of Glomerular Filtration of Water

Control of Glomerular Filtration by Hormones and Vasoactive Substances

AngiotensinII

Other Vasoconstrictor Substances

Vasodilator Substances

Other Hormones and Vasoactive Substances

Autoregulation of Glomerular Filtration Rate

Neural Regulation of Glomerular Filtration Rate

Theoretical Models of Glomerular Ultrafiltration

Glomerular Permselectivity

Experimental Approaches

Effects of Molecular Properties on Macromolecule Filtration

Theory of Glomerular Permselectivity

Glomerular Membrane Parameters

Determinants of Macromolecule Filtration

Estimation of Filtration Pressure from Sieving Data

Altered Glomerular Permselectivity
Nephron Heterogeneity
Authors: Hebert Steven C.
Published: November 2010

The sections in this article are:

Heterogeneity of Nephrons According to Location of Glomerulus and Length of Loop of Henle

Heterogeneity of Nephron Regions

Proximal Tubule

Structural/Morphological Heterogeneity

Functional Heterogeneity

The Intermediate Tubule (Thin Limbs of Henle's Loop)

Structural/Morphological Heterogeneity

Functional Heterogeneity

Distal Tubule

Thick Ascending Limbs of Henle's Loop (TAL)

Distal Convoluted Tubule (DCT)

Collecting Duct

Structural/Morphological Heterogeneity

Functional Heterogeneity
Neural Control of Renal Function
Authors: Moss Nicholas G. , Colindres Romulo E. , Gottschalk Carl W.
Published: November 2010

The sections in this article are:

Current Research

Historical Perspective

Neuroanatomy and Neurophysiology

Efferent Renal Innervation

Afferent Renal Innervation

Renal Adrenergic Receptors

General Concepts

Prejunctional Renal Receptors

Post‐ and Extrajunctional Adrenoceptors

Renal Tubular and Vascular Dopamine Receptors

Renal Cholinergic Receptors

Cellular Transduction of Neurotransmitter Effects

Sympathetic Nervous System and Renal Hemodynamics

Vasoconstrictor Responses

Vasodilatory Responses

Sympathetic Nervous System and Renal Tubular Function

Studies in Anesthetized Animals

Studies in Conscious Animals

Effects of Neurotransmitters on Renal Tubular Function

Cellular Mechanisms in the Renal Tubular Responses to Catecholamines

Sympathetic Nervous System and Renin Secretion by the Kidney

General Concepts

Effects of Direct and Reflex Stimulation of the Renal Nerves

Effects of Renal Denervation on Renin Release

Renal Adrenoceptors Involved in Renin Secretion

Interactions Between Nerves and Prostaglandins in Renin Release
Tubuloglomerular Feedback Control of Renal Vascular Resistance
Authors: Schnermann Jürgen , Häberle Dieter A. , Davis John M. , Thurau Klaus
Published: November 2010

The sections in this article are:

Historical Background

TGFResponse Characteristics

Open‐Loop Studies

Closed‐Loop Studies

Mechanisms of theTGFReaction

Anatomical Pathway

Luminal Signal

Stimulus–Response Coupling Mechanisms

The Vascular Reaction

Integrative Feedback Function

Mechanisms ofTGFResetting

Phenomenology ofTGFResponsiveness