bluuebunny/crossref_metadata_2025 huggingface dataset:
Scattering theory for the cubic nonlinear Klein–Gordon system
Authors: Zhang Junyong
Published: January 2013

In this paper, we consider the scattering theory of a nonlinear Klein–Gordon system, which describes the interaction of two scalar fields. The analysis in this paper is an adaptation of the technique used by Nakanishi, which is originally due to Bourgain. The new technical point appears in the localization argument of proving a concentration phenomenon. Copyright © 2013 John Wiley & Sons, Ltd.
Neuropeptides trigger oocyte maturation and subsequent spawning in the hydrozoan jellyfish Cytaeis uchidae
Authors: Takeda Noriyo , Nakajima Yoko , Koizumi Osamu , Fujisawa Toshitaka , Takahashi Toshio , Matsumoto Midori , Deguchi Ryusaku
Published: January 2013

Oocyte maturation and subsequent spawning in hydrozoan jellyfish are generally triggered by light‐dark cycles. To examine if the initiation of the maturation process after light stimulus is mediated by neurotransmitters, neuropeptides isolated originally from Hydra magnipapillata were applied to sexually mature female medusae of the hydrozoan jellyfish Cytaeis uchidae. Among the Hydra neuropeptides tested, Hym‐53 (NPYPGLW‐NH2), as well as a nonphysiological peptide, CGLWamide (CGLW‐NH2), were most effective in inducing oocyte maturation and spawning. Hym‐355 (FPQSFLPRG‐NH2) also triggered these events, but the stimulatory effect was weaker. Since Hym‐53‐OH (NPYPGLW) and Hym‐355‐OH (FPQSFLPRG) had no effect, amidation at the C‐terminus may be critical for the stimulatory activities of the peptides. Exposure to Hym‐53 for 2 min was sufficient to trigger of oocyte maturation, and the spawned eggs were able to be fertilized and to develop normally. Transmission electron microscopy confirmed that bundles of axon‐like structures that contain dense‐core synaptic vesicles and microtubules are present in the ovarian ectodermal epithelium overlying the oocytes. In addition, immunohistological analyses revealed that some of the neurons in the ectodermal epithelium are GLWamide‐ and PRGamide‐positive. These results suggest that a neuropeptide signal transduction pathway is involved in mediating the induction of oocyte maturation and spawning in this jellyfish. Mol. Reprod. Dev. 80: 223–232, 2013. © 2013 Wiley Periodicals, Inc.
Study of Plastic Explosives based on Attractive Cyclic Nitramines, Part II. Detonation Characteristics of Explosives with Polyfluorinated Binders
Authors: Elbeih Ahmed , Pachman Jiri , Zeman Svatopluk , Trzcinski Waldemar A. , Suceska Muhamed
Published: January 2013

A series of plastic bonded explosives (PBXs) based on Viton A and Fluorel binders were prepared using four nitramines, namely RDX (1,3,5‐trinitro‐1,3,5‐triazinane), β‐HMX (β‐1,3,5,7‐tetranitro‐1,3,5,7‐tetrazocane), BCHMX (cis‐1,3,4,6‐tetranitro‐octahydroimidazo‐[4,5‐d]imidazole), and ε‐HNIW (ε‐2,4,6,8,10,12‐hexanitro‐2,4,6,8,10,12‐hexaazaisowurtzitane). The detonation velocities, D, were determined. Detonation parameters were also calculated by means of modified Kamlet & Jacobs method, CHEETAH and EXPLO5 codes. In accordance with our expectations BCHMX based PBXs performed better than RDX based ones. The Urizar coefficient for Fuorel binder was also calculated.
Modeling of Ignition in a Single Layer of Impacted Energetic Crystals
Authors: Wu Yan‐Quing , Huang Feng‐Lei , Huang Ming
Published: January 2013

A thermal‐mechanical model for the ignition of a layer of cyclotetramethylene tetranitramine (HMX) particles under drop‐weight impact was developed. Considering the micro‐particle plasticity, frictional heating, melting, fracture, and chemical reaction at particle level, effects of loading parameters and sample characteristics on ignition and mechanical responses were discussed. The threshold values for ignition to occur under different loading conditions and various material parameters can be predicted. The model was validated by comparing experimental measured and calculated mean pressure‐strain curves, which showed two turning points due to localized fragmentation and melting. Relationships between thermal and mechanical responses at the particle level were examined.
Factors Influencing Triacetone Triperoxide (TATP) and Diacetone Diperoxide (DADP) Formation: Part I
Authors: Oxley Jimmie C. , Smith James L. , Bowden Patrick R. , Rettinger Ryan C.
Published: January 2013

Conditions, which result in the formation of triacetone triperoxide (TATP) or diacetone diperoxide (DADP) from acetone and hydrogen peroxide (HP, were studied for the purposes of inhibiting the reaction. Reaction of HP with acetone precipitates either DADP or TATP, but the overall yield and amount of each was found to depend on (1) reaction temperature, (2) the molar ratio of acid to HP/acetone, (3) initial concentrations of reactants, and (4) length of reaction. Controlling molar ratios and concentrations of starting materials was complicated because both sulfuric acid and hydrogen peroxide were aqueous solutions. Temperature exercised great control over the reaction outcome. Holding all molar concentrations constant and raising the temperature from 5 to 25 °C showed an increase of DADP over TATP formation and a decrease in overall yield. At 25 °C a good yield of TATP was obtained if the HP to acetone ratio was kept between 0.5 : 1 and 2 : 1. At constant temperature and HP‐to‐acetone held at one‐to‐one ratio, acid‐to‐HP molar ratios between 0.10 : 1 and 1.2 : 1 produced good yield of TATP. Plotting the molality of HP vs. that of sulfuric acid revealed regions, in which relatively pure DADP or pure TATP could be obtained. In addition to varying reaction conditions, adulterants placed into acetone were tested to inhibit the formation of TATP. Because there is much speculation of the relative stability, sensitivity, including solvent wetting of crystals, and performance of DADP and TATP, standard tests (i.e. DSC, drop weight impact, and SSED) were performed.
Solvent Free Microwave Assisted Isomerization of N‐Nitropyrazoles
Authors: Ravi Pasupala , Tewari Surya P.
Published: January 2013

This paper describes solvent‐free isomerization of N‐nitropyrazoles under microwave irradiation to achieve a new green chemistry procedure for the synthesis of C‐ nitropyrazoles in good to excellent yields. The presented procedure requires less time, offers simplified workup procedure, needs no obnoxious solvents, and may be used for the preparation of several C‐nitropyrazoles.
The effect of Ga‐doping on the defect chemistry of RE3Al5O12 garnets
Authors: Stanek C. R. , Jiang C. , Yadav S. K. , McClellan K. J. , Uberuaga B. P. , Andersson D. A. , Nikl M.
Published: January 2013

It has been recently shown that the addition of Ga to Lu3Al5O12 garnet (LuAG) removes the electron trapping associated with cation antisite defects. In this paper, we show via atomic scale simulations that the replacement of Al with Ga in LuAG actually lowers the energy of the antisite disorder process. Thus, we predict that Ga additions will lead to an increase of the antisite defect concentration and, in the absence of the electronic structure changes, would actually degrade the performance of the material. Since there are two crystallographically distinct Al sites in the garnet structure, we not only present results for complete replacement of Al with Ga, but also partial replacement for 40% (on 16a) and 60% (on 24d) of the Al with Ga. Our results support the explanation for Ga‐doping leading to improvement in garnet scintillator performance that relies on variations of the electronic structure rather than reduction of the antisite defect concentration.

magnified image

Cation antisite defects in RE3Al5O12 garnet, where small light gray atoms and large dark gray atoms are lattice Al and RE atoms, respectively. The constituents of the antisite defect pairs are labeled, and it should be noted that the Ga atom (blue) is similar in size to RE (green). Oxygen atoms are not shown for clarity.
Influence of Ir and La substitution on the thermal transport properties of YbRh2Si2
Authors: Stockert Ulrike , Pfau Heike , Hartmann Stefanie , Lausberg Stefan , Friedemann Sven , Krellner Cornelius , Wirth Steffen , Geibel Christoph , Steglich Frank
Published: January 2013

We investigate the influence of small amounts of Ir and La substitution on the low‐temperature thermal conductivity κ and thermopower S of YbRh2Si2. While the thermal conductivity is reduced in both cases due to the introduction of additional impurities, the effect on the thermopower is non‐uniform: Ir substitution leads to a reduction of the absolute value of the thermopower. This is attributed largely to an enhanced disorder scattering. On the other hand, La substitution increases the absolute thermopower values. We discuss the possibility that this is due to band structure modifications upon doping into the Yb sublattice.
Photonic band gap active waveguide filters based on dilute nitrides
Authors: Calò Giovanna , Grande Marco , Alexandropoulos Dimitris , Petruzzelli Vincenzo
Published: January 2013

The wavelength filtering characteristics of active defective Photonic Band Gap (PBG) waveguides based on dilute nitrides are examined. The analyzed structure is made of GaInNAs‐GaInAs MQW ridge waveguides in which a geometrical active defect in the periodic lattice induces selective transmission spectral regions centered at different wavelengths inside the PBG. The device show the advantage of simultaneous DWDM selective filtering and amplification of the filtered signal. The performances of the active PBG filters are investigated as a function of the geometrical and the electrical parameters. The analysis is performed by using proprietary codes, based on the Bidirectional Beam Propagation Method with the Method of Lines introducing the rate equations. Highly selective 9‐channel active filter with minimum value of the bandwidth at half‐height transmittance B3dB=0.12 nm has been calculated. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Point defects in calcite used to estimate the date of arrival of first settlers in central region of Brazil
Authors: Cano Nilo F. , Etchvarne Carlos A. , Munita Casimiro S. , Rocca Rene R. , Barbosa Renata F. , Watanabe Shigueo
Published: January 2013

A calcite formation was found on a rock‐wall painting at Chapada de Diamantina in a site in between Serra da Capivara National Park and Montalvania, Piaui, Brazil. Thermoluminescence and electron paramagnetic resonance (EPR) dating of this calcite gave an age of 40 to 55 ka, indicating that humans lived there prior to 40 ka ago. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
HVPE growth of GaN in the semipolar direction on planar Si(210)
Authors: Bessolov Vasily , Konenkova Elena , Shcheglov Mikhail , Sharofidinov Shukrillo , Kukushkin Sergey , Osipov Andrey , Nikolaev Vladimir
Published: January 2013

A layer of semipolar gallium nitride was grown on Si(210) substrate by hydride vapor phase epitaxy (HVPE). As a buffer a nanocrystalline layer of 3C‐SiC was used. It has been found that anisotropic strain of the growing nitride layer changed the crystallographic orientation of its surface: with increasing layer thickness orientation of the surface changed sequentially as follows: (0001), (10‐15), (10‐14), (10‐13) and, finally, (10‐12). (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Mechanisms behind efficiency droop and degradation in InGaN/GaN LEDs
Authors: Shmidt Natalia , Greshnov Andrew , Chernyakov Anton , Levinshtein Michael , Zakgeim Alexander , Shabunina Evgeniia
Published: January 2013

The results of low frequency noise studies in power blue InGaN/GaN LEDs with external quantum efficiency 30‐45% classified by leakage current (LC) values before and after degradation are reported. The LC values at V< 2V integrally characterize electrical properties of extended defect system (EDS) that is typical for InGaN/GaN LEDs. The smaller concentration of extended defects and length of dilatation, dislocation boundaries, the lower LC value is. It has been demonstrated that non‐radiative recombination processes (NRRP) localized in extended defect system (EDS) contribute in efficiency droop of LEDs at j  ≥ 10 A/cm2. The main characteristics of degradation processes such as: (1) increase in tunneling current values related with EDS, at U ≤ 2 V, (2) strong deterioration of p‐n junction rectification properties, (3) formation of conductive paths along EDS; (4) increase in non‐uniformity of current distribution, and (5) the formation of local overheating channels at j > 10 A/cm2 along EDS had been revealed. The NRRP are localized along EDS and can be considered as a general mechanism of efficiency droop and the ambiguous degradation process in power InGaN/GaN LEDs (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Nondestructive method for evaluation of electrical parameters of AlGaN/GaN HEMT heterostructures
Authors: Paszkiewicz Bogdan , Wosko Mateusz , Paszkiewicz Regina , Tlaczala Marek
Published: January 2013

Impedance spectroscopy methods were proposed for direct evaluation of electrical properties of the AlGaN/GaN heterostructures. The impedance spectra were measured using a two contact mercury probe. Application of the proper distributed elements equivalent circuits enabled to evaluate not only the typically obtained parameters of the heterostructures such as sheet carriers concentration and its pinch off voltage but also the dependence of the channel sheet resistance and the mobility of 2DEG on d.c. gate bias (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Inhibiting Roles of Berberine in Gut Movement of Rodents are Related to Activation of the Endogenous Opioid System
Authors: Feng Yajing , Li Yongyu , Chen Chunqiu , Lin Xuhong , Yang Yuehua , Cai Haidong , Lv Zhongwei , Cao Minghua , Li Kun , Xu Jing , Li Sainan , Jia Yijun
Published: January 2013

Although Berberine (BER) is popular in treating gastrointestinal (GI) disorders, its mechanisms are not clear yet. In order to investigate the effects and possible mechanism of BER on GI motility in rodents, we first explored GI motility by recording the myoelectrical activity of jejunum and colon in rats, and upper GI transit with a charcoal marker in mice. Then, the plasma levels of gastrin, motilin, somatostatin and glucagon‐like‐peptide‐1 (Glp‐1) were measured by ELISA or radioimmunoassay (RIA). Furthermore, endogenous opioid‐peptides (β‐endorphin, dynorphin‐A, met‐enkephalin) were detected by RIA after treatment with BER. Our results showed that BER concentration‐dependently inhibited myoelectrical activity and GI transit, which can be antagonized by opioid‐receptor antagonists to different extents. The elevated somatostatin and Glp‐1, and decreased gastrin and motilin in plasma, which were caused by BER application, also could be antagonized by the opioid‐receptor antagonists. Additionally, plasma level of β‐endorphin, but not dynorphin‐A and met‐enkephalin, was increased by applying BER. Taken together, these studies show that BER plays inhibiting roles on GI motility and up‐regulating roles on somatostatin, Glp‐1 and down‐regulating roles on gastrin, motilin. The pharmacological mechanisms of BER on GI motility and plasma levels of GI hormones were discovered to be closely related to endogenous opioid system. Copyright © 2013 John Wiley & Sons, Ltd.
Evaluation of physicochemical properties of a new group of SiO2/silane/POSS hybrid materials
Authors: Ciesielczyk Filip , Szwarc‐Rzepka Karolina , Jesionowski Teofil
Published: January 2013

Preparation of a new group of hybrid fillers, of SiO2/silane/oligomeric silsesquioxane type, characterised by specific desirable physicochemical properties, was studied. Synthetic SiO2 was precipitated by the emulsion method. At first, as a result of improved adhesion between SiO2 and selected POSS compound, SiO2 surface was functionalised with alkoxysilanes containing characteristics functional groups. Functionalised SiO2 was used in the process of hybrid filler preparation according to hydrolytic condensation using methacryl POSS® mixture. To evaluate potential application of such fillers, SiO2 systems, bifunctionalised using innovative method, were thoroughly characterised to determine their physicochemical properties as well as the effectiveness of functionalisation with silanes and POSS compound. Proposed method of SiO2 surface modification using selected alkoxysilanes and oligosilsesquioxanes is innovative and gives very promising results. Bifunctionalisation of inorganic fillers with those compounds will substantially extended the range of their applications and probably will lead to improvement of mechanical properties of final polymer composites and reduction in the cost of their production which is the main feature of this research. Copyright © 2013 John Wiley & Sons, Ltd.
A consistent description of intermetallic particle composition: An analysis of ten batches of AA2024‐T3
Authors: Hughes A. E. , Glenn A. M. , Wilson N. , Moffatt A. , Morton A. J. , Buchheit R. G.
Published: January 2013

Advances in electron microprobe analyses have made it possible to characterise large areas at very fine pixel size relatively quickly. In a recent study by some of the authors, a 2 × 2 mm2 area of AA2024‐T351 was mapped using a step size of approximately 0.4 µm. Both wavelength dispersive intensities as well as energy dispersive spectra were collected at each pixel thus forming a hyperspectral dataset. That study revealed a number of compositions within the AA2024‐T351, distributed as either individual particles or compositional domains within particles. In the current study, ten batches of sheet product were examined. Nine batches of relatively new product had a common set of compositions for the different particles types in the different batches, but exhibited variation in the number density of the different types of particles. An older batch, however, had a completely different profile of compositions for the particles. The compositions of intermetallic particles in newer batches did not match what would be considered textbook compositions, raising the possibility that improved processing and purity of new AA2024‐T351 might lead to different particle types to those considered to be typical for AA2024‐T351 sheet. Copyright © 2013 John Wiley & Sons, Ltd.
Surface segregation measurements of In and S impurities from a dilute Cu(In,S) ternary alloy
Authors: Madito M. J. , Swart H. C. , Terblans J. J.
Published: January 2013

The surface segregation of In and S from a dilute Cu(In,S) ternary alloy were measured using Auger electron spectroscopy coupled with a linear programmed heater. The alloy was linearly heated and cooled at constant rates. Segregation data of a linear heat run showed surface segregation of In that reached a maximum surface coverage of 25% followed by S, which reached a coverage of 30%. It was found that after In had reached a maximum surface coverage, it started to desegregate as soon as the S enriched the surface until In was completely replaced by S. The segregation parameters, namely, the pre‐exponential factor (D0), activation energy (Q), segregation energy (ΔG˚) and interaction energy (Ω) were extracted from the measured segregation data for both In and S segregation in Cu by simulating the measured segregation data with a theoretical segregation model (modified Darken model). The segregation parameters obtained for In segregation in Cu are D0 = 1.8 ± 0.5 × 10−5 m2 s−1, Q = 184.3 ± 1.0 kJ.mol−1, ΔG˚ = −61.4 ± 1.4 kJ.mol‐1, ΩCu−In = 3.0 ± 0.4 kJ.mol−1; for S segregation in Cu the parameters are D0 = 8.9 ± 0.5 × 10−3 m2 s−1, Q = 212.8 ± 3.0 kJ.mol−1, ΔG˚ = −120.0 ± 3.5 kJ.mol−1, ΩCu−S = 23.0 ± 2.0 kJ mol−1 and the In and S interaction parameter is ΩIn−S = −4.0 ± 0.5 kJ.mol−1. The initial parameters used for the Darken calculations were extracted from fits performed with the Fick's and Guttmann model. Copyright © 2013 John Wiley & Sons, Ltd.
Influence of surface pretreatments on the corrosion protection of sol–gel coated AA2024‐T3 aluminium alloy
Authors: Feng Z. , Liu Y. , Hashimoto T. , Thompson G. E. , Zhou X. , Skeldon P.
Published: January 2013

In the present study, the effects of surface pretreatments of AA2024 aluminium alloy on the corrosion protection of the alloy using a sol–gel coating were investigated. It was revealed that the second phase particles that remain after etching and desmutting have a significant impact on the subsequent sol–gel coating which, in turn, influences the overall corrosion protection afforded to the substrate by the sol–gel coating. The removal of second phase particles in the surface region can be achieved by an alternative surface pretreatment using nitric acid. A significant improvement of corrosion protection of sol–gel coated AA2024 aluminium alloy was observed when the surface of the alloy was pretreated with nitric acid. Copyright © 2013 John Wiley & Sons, Ltd.
Reducing cost in sequential testing: a limit of indifference approach
Authors: Ahmed Anwar E. , Schubert Christine M. , McClish Donna K.
Published: January 2013

In noninferiority studies, a limit of indifference is used to express a tolerance in results such that the clinician would regard such results as being acceptable or ‘not worse’. We applied this concept to a measure of accuracy, the Receiver Operating Characteristic (ROC) curve, for a sequence of tests. We expressed a limit of indifference for the range of acceptable sensitivity values and examined the associated cost of testing within this range. In doing so, we generated the minimum cost maximum ROC (MCMROC) curve, which reflects the reduced sensitivity and cost of testing. We compared the MCMROC and its associated cost curve between limits of indifference set to 0.999 [a 0.1% reduction in true positive rate (TPR)], 0.95 (a 5% reduction in TPR), and 1 (no reduction in TPR). The limit of indifference tended to have less of an effect on the MCMROC curves than on the associated cost curves that were greatly affected. Cost was reduced at high false positive rates (FPRs) at higher limit of indifference (0.999) and at small FPRs as the limit of indifference decreased (0.95). These patterns were also observed as applied to sequential strategies used to diagnose diabetes in the Pima Indians. Copyright © 2013 John Wiley & Sons, Ltd.
Hot Strength and Creep Resistance of a High Interstitial Austenitic CrMn Steel
Authors: Berns Hans , Geenen Karina
Published: January 2013

The hot strength and short‐time creep resistance of austenitic steel CN0.85 with about (mass%) 18Cr, 18Mn, 0.6N, and 0.25C was investigated up to 700°C together with the corresponding structural changes of the solution annealed or cold worked initial states. In the primary creep range, the creep rate was rapidly reduced to the minimum creep rate and the more so after initial cold working. This also lowered the minimum creep rate but hardly the time to fracture. Precipitation of carbides and nitrides occurred in or near grain boundaries which gave rise to creep cracks. Precipitates within the grains, visible only in the overaged state, are assumed to have raised the resistance to creep. Comparing the creep strength of CN0.85 with standard hot work tool steel H11 points to an advantage of the former at service temperatures of >550°C. However, tests in practice are required to back up the favorable results of this tentative study.
Modeling the Viscosity of Alumino‐Silicate Melt
Authors: Zhang Guo‐Hua , Chou Kuo‐Chih
Published: January 2013

The structurally based viscosity model for aluminosilicate melts is developed, in which the influence of melt structure on viscosity is expressed by the definitions of different types of oxygen ions: (i) bridging oxygen OSi, bonded to Si4+ ions (ii) non‐bridging oxygen ${\rm O}_{{\rm Si}}^{i} $, bonded to Si4+ ion and cation i from basic oxide, (iii) free oxygen Oi, bonded to i ions, (iv) bridging oxygen OAi,i, bonded to an Al3+ ion charge compensated by cation i; (v) non‐bridging oxygen ${\rm O}_{{\rm Al, }i}^{j} $, bonded to the metal cation j and Al3+ ion charge compensated by cation i; (vi) oxygen OAl, bonded to an Al3+ ion which is not charge compensated. A systematic method is proposed to calculate numbers of these oxygen ions. According to the calculation results of the viscosity model, it has been found that the abilities of basic oxides to decrease viscosity follow the order: FeO > MnO > CaO > MgO, when Al2O3 is absent. The viscosities of quinary, quarternary, ternary, binary, and unary systems involving MgO, CaO, FeO, MnO, Al2O3, and SiO2 components are calculated by the present model, with all the mean deviations not >30%. Furthermore, it is indicates a better precision of the present model than that of other models for the same systems.
Differentiation-Related Response to DNA Breaks in Human Mesenchymal Stem Cells
Authors: Oliver Lisa , Hue Erika , Séry Quentin , Lafargue Audrey , Pecqueur Claire , Paris François , Vallette François M.
Published: January 2013

We have recently shown that the in vitro differentiation of human mesenchymal stem cells (hMSCs) was accompanied by an increased sensitivity toward apoptosis; however, the mechanism responsible for this shift is not known. Here, we show that the repair of DNA double-strand breaks (DSBs) was more rapid in undifferentiated hMSCs than in differentiated osteoblasts by quantification of the disappearance of γ-H2AX foci in the nuclei after γ-irradiation-induced DNA damage. In addition, there was a marked and prolonged increase in the level of nuclear Ku70 and an increased phosphorylation of DNA-PKcs. This was accompanied by an augmentation in the phosphorylation of ATM in hMSCs post-irradiation suggesting the nonhomologous end joining repair mechanism. However, when hMSCs were induced to differentiate along the osteogenic or adipogenic pathways; irradiation of these cells caused an expeditious and robust cell death, which was primarily apoptotic. This was in sharp contrast to undifferentiated hMSCs, which were highly resistant to irradiation and/or temozolomide-induced DSBs. In addition, we observed a 95% recovery from DSB in these cells. Our results suggest that apoptosis and DNA repair are major safeguard mechanisms in the control of hMSCs differentiation after DNA damage.
An “ex vivo” model to evaluate toxicological responses to mixtures of contaminants in cetaceans: Integumentum biopsy slices
Authors: Fossi Maria Cristina , Casini Silvia , Maltese Silvia , Panti Cristina , Spinsanti Giacomo , Marsili Letizia
Published: January 2013

The need for powerful new tools to detect the effects of chemical pollution, in particular of persistent organic pollutants (POPs) and polycyclic aromatic hydrocarbons (PAHs) on Mediterranean cetaceans led us to develop and apply a suite of sensitive biomarkers for integument biopsies of stranded and free‐ranging animals. This multi‐responseex vivomethod has the aim to detect toxicological effects of contaminant mixtures. In the present study, we applied anex vivoassay using skin biopsy and liver slices, combining molecular biomarkers [Western blot of Cytochrome P450 1A1 (CYP1A1) and Cytochrome P450 2B (CYP2B)] and gene expression biomarkers (Quantitative real‐time PCR of CYP1A1, heat shock protein 70, estrogen receptor alpha and E2F transcription factor) in response to chemical exposure [organochlorines compounds (OCs), polybrominated diphenyl ethers (PBDEs), and PAHs] for stranded MediterraneanStenella coeruleoalba. The main goal of this experiment was to identify the biomarker and/or a suite of biomarkers that could best detect the presence of a specific class of pollutants (OCs, PBDEs, and PAHs) or a mixture of them. This multi‐response biomarker methodology revealed an high sensitivity and selectivity of responses (such as CYP1A and ER α mRNA variations after OCs and PAHs exposure) and could represent a valid future approach for the study of inter‐ and intra‐species sensitivities to various classes of environmental contaminants. © 2013 Wiley Periodicals, Inc. Environ Toxicol 29: 1107–1121, 2014.
Side‐effects of thiamethoxam on the brain andmidgut of the africanized honeybee Apis mellifera (Hymenopptera: Apidae)
Authors: Oliveira Regiane Alves , Roat Thaisa Cristina , Carvalho Stephan Malfitano , Malaspina Osmar
Published: January 2013

The development of agricultural activities coincides with the increased use of pesticides to control pests, which can also be harmful to nontarget insects such as bees. Thus, the goal of this work was assess the toxic effects of thiamethoxam on newly emerged worker bees of Apis mellifera (africanized honeybee—AHB). Initially, we determined that the lethal concentration 50 (LC50) of thiamethoxam was 4.28 ng a.i./μL of diet. To determine the lethal time 50 (LT50), a survival assay was conducted using diets containing sublethal doses of thiamethoxam equal to 1/10 and 1/100 of the LC50. The group of bees exposed to 1/10 of the LC50 had a 41.2% reduction of lifespan. When AHB samples were analyzed by morphological technique we found the presence of condensed cells in the mushroom bodies and optical lobes in exposed honeybees. Through Xylidine Ponceau technique, we found cells which stained more intensely in groups exposed to thiamethoxam. The digestive and regenerative cells of the midgut from exposed bees also showed morphological and histochemical alterations, like cytoplasm vacuolization, increased apocrine secretion and increased cell elimination. Thus, intoxication with a sublethal doses of thiamethoxam can cause impairment in the brain and midgut of AHB and contribute to the honeybee lifespan reduction. © 2013 Wiley Periodicals, Inc. Environ Toxicol 29: 1122–1133, 2014.
Protective role of silymarin against manganese‐induced nephrotoxicity and oxidative stress in rat
Authors: Chtourou Yassine , Garoui El mouldi , Boudawara Tahia , Zeghal Najiba
Published: January 2013

Metal toxicity may occur after exposure from many sources. Oxidative stress is thought to be involved in manganese‐induced toxicity and leads to various health disorders. Silymarin (SIL), a natural flavonoid, has been reported to have many benefits and medicinal properties. The aim of this study was to assess the toxicity of manganese (Mn) on oxidative stress and DNA damage in the kidney of rats and its alleviation by SIL. Manganese was given orally in drinking water (20 mg MnCl2/mL) with or without SIL administration (100 mg /kg intraperitoneally) for 30 days. Our data showed that SIL significantly prevented Mn induced nephrotoxicity, indicated by both diagnostic indicators of kidney injury like plasma urea, uric acid and creatinine and urinary electrolyte levels and by histopathological analysis. Moreover, Mn‐induced profound elevation of the production of reactive oxygen species (ROS) and altered the levels of oxidative stress related biomarkers in kidney tissue. This is evidenced by the increase of lipid peroxidation, protein carbonylation, DNA fragmentation and urinary hydrogen peroxide, while, the activities of enzymatic antioxidant and glutathione level were decreased. Treatment with SIL reduced the alterations in the renal and urine markers, decreasing lipid peroxidation markers, increasing the antioxidant cascade and decreasing the Mn‐induced damage. All these changes were supported by histopathological observations. These findings suggested that the inhibition of Mn‐induced damage by SIL was due at least in part to its antioxidant activity and its capacity to modulate the oxidative damage. © 2013 Wiley Periodicals, Inc. Environ Toxicol 29: 1147–1154, 2014.
Mosquito Net Mesh for Abdominal Wall Hernioplasty: A Comparison of Material Characteristics with Commercial Prosthetics
Authors: Sanders David L. , Kingsnorth Andrew N. , Stephenson Brian M.
Published: January 2013

Background

The use of sterilized mosquito net as a cheaper alternative to commercial mesh used in hernia repair has previously been published. However, as no standards with regard to the material have been documented, we aimed to define the characteristics of a commonly available and low‐cost mosquito net, which has already been shown to be clinically efficacious in groin hernia repair. We compared its characteristics to other commercially available meshes, in keeping with the well‐established FDA and MHRA regulatory processes.

Methods

The macromolecular structure of the mosquito net was determined by vibrational spectroscopy. The ultrastructure of the meshes was examined with scanning electron microscopy, and uniaxial and burst tensile strength testing was performed. The following parameters were assessed: polymer type, filament characteristics, pore size, weight, linear density, elasticity, and tensile strength.

Results

The mosquito net was a polyethylene homopolymer, knitted from monofilament fibers with a mean filament diameter of 109.7 μm and a mean mesh thickness of 480 μm. The mean pore maximum diameter was 1.9 mm, with 91.2 % porosity, 53.7 g/m2 mean mesh weight, and a linear mass density of 152 denier. This was comparable to the “large pore” (class I) commercial meshes. The bursting force for polyethylene mosquito net was greater than for UltraPro and Vypro (43.0 vs. 35.5 and 27.2 N/cm, respectively), and the mosquito net exhibited less anisotropy compared to the commercial meshes.

Conclusions

The material and mechanical properties of the polyethylene mosquito net are substantially equivalent to those of commonly used lightweight commercial meshes.
Identifying and Addressing Preventable Process Errors in Trauma Care
Authors: Pucher Philip H. , Aggarwal Rajesh , Twaij Ahmed , Batrick Nicola , Jenkins Michael , Darzi Ara
Published: January 2013

Background

Management of the acute trauma patient is complex, with potential for error and adverse events. Avoidable injuries and deaths are not well understood. Analysis of error incidence, type, and severity can aid in greater understanding of the root causes and guide future development of error reduction strategies.

Methods

Weekly case review meetings for a UK trauma center were retrospectively reviewed over 1 year. Errors were identified and corroborated with case‐note review by a reviewer blinded to any identified events. All events were classified according to the Joint Commission on Accreditation of Healthcare Organisations taxonomy and were typified as structural or process errors and omission or commission errors.

Results

A total of 1,752 major trauma patients were admitted over the study period, and 169 preventable errors were identified through analysis of case review meetings and case‐note review. Clear patient harm was identified in 3.6 % of cases, with risk of harm in 30 %. Most errors occurred during the initial phase of care in the emergency department (51 %) and resulted most commonly in delays (56 %). The majority of errors were identified as process‐related (88 %), with 62 % of them considered errors of omission.

Conclusions

This study reports error incidence in trauma and typifies them according to type and root cause. It identifies process errors and errors of omission in particular as the most common recurring events. Error theory suggests that protocols or checklists may most effectively address these errors. Further study should be prospective and may aid in the development of such interventions.
Late Quaternary Deformation and Palaeoseismicity: Insight into Geomorphotectonic Evolution of Kachchh, Western Indian Subcontinent
Authors: Roy A. B. , Chatterjee Alokesh , Chauhan N. K.
Published: January 2013

Kachchh in western Indian Shield, according to the Bureau of Indian Standard (IS:1893:2002), falls in Seismic Zone V. This is intriguing considering that the region is far away from active Plate margin. Apart from the recent incidences of earthquakes, there are several pre-historic/archaeological records of earthquakes in the region. Beyond these, the geological evidence of earth-movements (causing earthquakes) is provided by the occurrence of several ‘active’ faults, which are considered geological markers of palaeoseismicity. There are records of innumerable incidences of faulting in the region in not so distant geological past. Study of fault features especially the scarp faces marking abrupt change in physical relief proves that the different levels of topography in the entire terrain are fault-bound features. Studies also confirm that the topographic difference between the high and ‘sunken’ features have formed due to uplift and relative down-sagging during the geomorphotectonic evolution of the terrain. Features that make the region unique are: (i) restriction of fault-related deformation zone to a narrow strip between the southern margin of Thar Desert and the south coast line of the Kachchh Peninsula; (ii) overall sub-horizontality of bedding and other topographic and planation surfaces over the entire region; (iii) evidence of fault-controlled geomorphology indicating vertical movement along fault planes; (iv) evidence constraining the time of geomorphological evolution of the terrain only during the Late Quaternary, making it the youngest neotectonically evolved terrain in the Precambrian Indian Shield.
First Carbonatite Hosted REE Deposit from India
Authors: Bhushan S. K. , Kumar Ashish
Published: January 2013

Based on geological mapping and grid channel geochemical sampling, a carbonatite plug hosted REE deposit has been discovered at Kamthai, Barmer district, Rajasthan. The main REE minerals hosted by carbonatite plug are bastanesite (La), basnaesite (Ce), synchysite (Ce), carbocernaite (Ce), cerianite (Ce), ancylite and parisite. The highest value of LREE is 17.31%, whereas, mean works out 3.33% and weighted average is 2.97%. The carbonatite plug covers 19475 sq. meters and the resources have been estimated upto 84 m depth under Proved, Probable and Possible categories. The total resource estimation for carbonatite plug and other carbonate sills, dykes and veins is 4.91 million tons, making this as truly world class deposit. The TMC of individual LREO (lower rare earth oxide) calculated for carbonatite plug only are La=52196 tonnes, Ce =66026 tonnes, Nd = 13663 tonnes, Pr = 5415 tonnes, Sm = 920 tonnes and Eu = 207 tonnes. Besides these REE, the Kamthai resource will produce 551 tonnes of Ga, 44 tonnes of Ge and 1,12,830 tonnes of SrO during its mining life.
Leukocyte cell‐derived chemotaxin 2 is a zinc‐binding protein
Authors: Okumura Akinori , Suzuki Takehiro , Miyatake Hideyuki , Okabe Tomoya , Hashimoto Yuki , Miyakawa Takuya , Zheng Hai , Unoki-Kubota Hiroyuki , Ohno Hideaki , Dohmae Naoshi , Kaburagi Yasushi , Miyazaki Yoshitsugu , Tanokura Masaru , Yamagoe Satoshi
Published: January 2013

LECT2
and LECT2
bind by comigration in gel electrophoresis (View interaction: 1, 2, 3)
The ‘Come and Go’ Syndrome of Teachers in Remote Indigenous Schools: Listening to the Perspective of Indigenous Teachers about What Helps Teachers to Stay and What Makes Them Go
Authors: Hall Lisa
Published: January 2013

High turnover of teachers in remote Indigenous community schools in the Northern Territory has long been considered a significant contributing factor to low academic outcomes for students in those communities. The average length of stay for a non-Indigenous teacher in a remote school can more easily be measured in months than years. This instability in staffing is largely responsible for the instability experienced by many students in these schools. This ‘Come and Go’ syndrome holds true for non-Indigenous staff; however, the opposite can often be said of Indigenous staff. Indigenous staff in these schools tend to be the ‘Stay and Stay and Stay’ teachers. They have often worked in their local community school for decades and have seen literally hundreds of non-Indigenous teachers ‘Come and Go’. They have been the ones to provide a semblance of stability and some level of program sustainability in education for the children of their own communities. While there is some qualitative data on the things that improve retention of non-Indigenous teachers in rural and remote schools, it mostly looks at the training and skills development that can be applied to the situation. No one has really ever asked Indigenous teachers for their observations or opinions about what makes teachers stay and what makes them go. This article will draw on conversations from two focus groups of Indigenous teachers from remote schools in Central Australia who were invited to discuss just this question.
Reflective Teaching Practice in a Darug Classroom: How Teachers can Build Relationships With an
Aboriginal Community Outside the School
Authors: Harrison Neil , Murray Belinda
Published: January 2013

This project has been developed on Darug country, Sydney to examine how pre-service and beginning teachers
can work with Aboriginal people in their local urban community. These teachers often want to know how to
approach an Aboriginal ‘community’, how they can ask Aboriginal people for information in order to include it
in their teaching, and how to adopt respectful ways of talking when they contact a community member. While
these questions are commonly addressed in the Working with Community documents published by
the various state Departments of Education, we found that the actual practice of working with a community is
daunting for many. This article therefore attempts to document two examples of this practice, and in so doing
it applies the protocols identified by Martin (2008) to the reflective work of both a pre-service teacher and
a university educator. It also draws on the extensive literature of reflective practice developed for
classrooms, and applies this to pedagogical practice outside schools.
An Integrative Review on the San of Botswana's Indigenous Literacy and Formal Schooling
Education
Authors: Ketsitlile Lone
Published: January 2013

The San are Southern Africa's first indigenous peoples. They can be found in South Africa, Botswana, Zimbabwe
and Namibia. The San peoples in Botswana still face discrimination, especially in the education sector, as
their indigenous literacy and way of life are largely ignored. Their languages are not part of the school
curriculum in Botswana and it is English (the official language) and Setswana (the national language) that are
taught in schools. In theory, this should not be the case. This highly disadvantages San children as they
underperform and drop out of school. Hence, very few have made it to the University of Botswana and the
Colleges of Education. In order for Botswana to reach its aim of an educated and informed nation by 2016, San
peoples need to be catered for in the education system of Botswana. This article is an integrative review
about the San of Botswana and (1) explains what has been studied about the San with regard to their indigenous
ways of knowing and reading the world; (2) gives a clear picture of their formal schooling experiences; and,
(3) provides an overview of their English and Setswana language acquisition.
‘So, What is Wrong with Indigenous Education?’ Perspective, Position and Power
Beyond a Deficit Discourse
Authors: Vass Greg
Published: January 2013

It is the aim of this article to provoke debate and encourage greater scrutiny regarding the use and meaning
of the expression ‘Indigenous education’ within the discursive practices, research and policy in Australian
education. Drawing on Hall's (2007) development of ideas from Foucault that give rise to ‘Indigenous
education’ being viewed as a ‘regime of truth’, it is my contention that the widespread and largely uncritical
use of this expression is contributing to sustaining deficit assumptions regarding the engagement and outcomes
of Indigenous students within Australian schools. To explore this concern, I will first ‘archaeologically’
excavate (Scheurich, 1997) the emergence of this ‘regime’ within the Australian setting. Following on from
this, I will discuss and reflect upon recent debates associated with initiatives designed to ‘close the gap’
when comparing Indigenous and non-Indigenous student achievements in education. Given the changes inaugurated
by the Labor-led ‘Education Revolution’ since 2007, this is a particularly pertinent line of inquiry to take
up, with the focus of this article largely concerned with its impact in the Queensland setting.
QUESTIONS OF OWNERSHIP: PROPRIETORSHIP AND CONTROL IN A CHANGING RURAL TERRAIN – A CASE STUDY FROM GHANA
Authors: Berry Sara
Published: January 2013

Using a case study of a rural town in the Ashanti Region, this article explores transformations in enterprise, property relations and informal governance that have occurred since Ghana embarked on a period of neo-liberal economic and political restructuring in the mid-1980s. Rather than a linear move away from state-controlled markets and authoritarian rule toward privatization and democratic decentralization, Ghana has witnessed a proliferation of authorities and economic enterprises, both formal and informal, that defy clear-cut distinctions between public and private property and institutions. In the town described here, as in many other localities in Ghana, chiefs have figured prominently as both instigators and examples of transformations in economic and governing practices and institutions.
POINTING TO PROPERTY: COLONIALISM AND KNOWLEDGE ABOUT LAND TENURE IN NORTHERN NIGERIA
Authors: Pierce Steven
Published: January 2013

Colonial contact created many African ‘traditions’ that are in fact novel; part of this process involved translation, in which cultural accommodations were determined not just by the political interests of negotiators but by the challenges of moving between languages and conceptual universes. This article focuses on the cultural translation of land tenure and property in colonial northern Nigeria, as legal paradigms and principles of governance. Beginning in the early colonial period, Western paradigms came to shape the ways colonial authorities understood indigenous landholding, which in turned influenced how they governed small-scale farmers. The article traces how different intellectual traditions came together to create a ‘traditional’ system of land tenure with very little purchase on past practices, and a somewhat attenuated relationship with the lives of ordinary farmers.
V.—The Geology of Ardgour, Argyllshire
Authors: Drever H. I.
Published: January 2013

Between 1897 and 1903 Ardgour was investigated and surveyed for the Geological Survey by J. S. Grant Wilson. His results were published in the Summaries of Progress of the Geological Survey for 1897, 1898, 1900, and 1903, and were later included in Sheet 53 of the Survey's 1 inch to 1 mile maps and in the Glencoe Memoir. Little additional work had been attempted until 1933 when R. M. Shackelton commenced remapping the area. Shackelton was prevented from completing this work, and the writer supplanted him to continue research on the area from 1934 to 1937 under the direction of Professor C. E. Tilley.

The Ardgour estate comprises a rugged, mountainous tract of Argyllshire north of Loch Linnhe. One large and several smaller masses of epidiorite discovered by Grant Wilson (text-fig. 1) have been intruded into rocks of the Moine Series. Apart from large areas occupied by felspathic granulite and other quartzose types there are also limestones in an amount unusual in the normal Moine Series, some finely banded hornfelses and a zone surrounding the epidiorite masses composed apparently of a felspathised or granitised granulite (indicated by a broken line in text-fig. 1). Pelitic types are important in the western part of the area, and, round Sgurr Dhomhnuill in particular, they have apparently been injected by acid material. This at least is the present view, although the ground has yet to be thoroughly studied. There are a number of lamprophyre and basalt dykes, and some granite, in most places brecciated (with the occasional production of mylonite, e.g. Ben Ba), occurs along the line of the Great Glen Fault. Most of the ground is well exposed, although there may be glacial deposits inland and marine deposits round the coast (not differentiated in text-fig. 1).