bluuebunny/crossref_metadata_2025 huggingface dataset:
Some aspects of methods for measuring consistence
Authors: Popovics Sándor
Published: July 2012

Summary

A brief, general description is presented of the K-procedure for the prediction of consistence. From this, a thinning factor K is developed for the standard compacting factor test. Numerical values of K are presented for practical application. An example illustrates the use of Tables for the estimation of water quantity which is needed for a given value of the compacting factor. The equations presented show good agreement with test results obtained by several investigators. Finally, the virtues of the standard slump test are demonstrated.
The lateral stiffness and strength required to ensure membrane action at the ultimate load of a reinforced concrete slab-and-beam floor
Authors: Park R.
Published: July 2012

Summary

The lateral stiffness and strength required of supporting beams and exterior panels of continuous reinforced concrete slab-and-beam floors in order to ensure membrane action in the panels at ultimate load is considered. It is shown that tie reinforcement may be required in the supporting beams to carry the membrane forces. Tests on twenty small-scale mortar models of idealized nine-panel slab-and-beam floors with the interior panel uniformly loaded are described. The tests illustrated the modes of failure of exterior panels with insufficient reinforcement to resist the reactire forces due to the membrane action of the interior panel. The ultimate loads of interior panels of the slabs with adequately reinforced exterior panels showed good agreement with theory derived previously (which included the effect of axial strains in the panel and lateral movement of the edges due to extension of the tie steel) once the concrete had cracked.
Changes in weight and dimensions in the drying and carbonation of Portland cement mortars
Authors: Kamimura K. , Sereda P. J. , Swenson E. G.
Published: July 2012

Summary

Small specimens of mortar and paste were cured for 28 days and then subjected to various conditions of drying and carbonation. In general the extent of carbonation, for a given CO2 concentration, depends upon permeability, moisture content and time, but the extent of carbonation shrinkage and ultimate volume stability depend on the compressibility of the aggregate, the water/cement ratio, the maturity of the paste, the drying environment and rate, and on the sequence of drying and carbonation. Some of the practical implications of these results are noted.
The design and construction of a chamber with controlled temperature and humidity
Authors: King J. W. H. , Timusk J.
Published: July 2012

Summary

The paper describes the design and construction of a 9 × 15 × 7 ft high enclosure for controlling temperature to ± 1 degC and humidity to within ±2%.
The effect of various sulphate solutions on the strength and other properties of cement mortars at temperatures up to 80°C
Authors: Richards John D.
Published: July 2012

Summary

The results indicate that small rises in temperature can reduce and often prevent deterioration of Portland cement mortars in sulphate media, although rises in temperature cause loss of strength in other cements due to changes in crystal structure. The resistance of mortars to the more aggressive magnesium and ammonium sulphates at higher temperatures and the small expansion which occurs above 40°C are conclusively demonstrated.
Tests on end-zone stresses in pre-tensioned concrete I beams
Authors: Arthur P. D. , Ganguli S.
Published: July 2012

Summary

A series of tests to measure the strains in the endzones of pre-tensioned prestressed concrete I beams is described. The variables were limited to the web breadth and the arrangement of prestressing wires. The maximum stress on the end face of a beam when horizontal cracking occurred was found to bear a linear relationship to the cube strength of the concrete at transfer. The strain at cracking was virtually constant. Peak tensile stresses on the end faces as predicted by various methods are compared with stresses obtained from measured strains, and suggestions are made for approximate predictions of stresses. A procedure is proposed for determining whether cracking is likely.
Tricalcium aluminate and related phases in Portland cement
Authors: Moore A. E.
Published: July 2012

Summary

The paper reports an X-ray diffraction study of the effect of impurities on the structure of tricaldum aluminate. A number of workers have shown that Fe2O3 can replace some of the Al2O3 in C3A, and that this is accompanied by an increase in cell size. Estimates of the limiting composition vary from 2 to 10 molar % C3F/(C3F + C3A); the reasons for these differences are discussed. It is shown that silica and magnesia can also enter the C3A lattice and both cause a decrease in the unit cell size. In all the preceding cases the C3A remains cubic; this is also true for additions of Na2O up to about 3 molar %; with higher concentrations the structure becomes orthorhombic. Some measurements of cell size of C3A extracted from Portland cement are also given. In the light of these findings, a structure is postulated for C3A which differs in important respects from the currently accepted one, of Büssem and Eitel.
Redistribution of moments in prestressed concrete continuous beams
Authors: Mallick S. K. , Sastry M. K. L. N.
Published: July 2012

Summary

Twenty-seven three-span and twelve two-span beams, all of rectangular cross-section, were tested to destruction under various arrangements of concentrated loads. The results of these tests are presented. Redistribution of moments was practically complete in the majority of the beams. The curvature distributions along the plastic lengths have been studied and the rotations deduced therefrom are compared with those obtained on the basis of the standard moment-curvature relationship proposed by Guyon.
Some fatigue tests of high-strength concrete in axial compression
Authors: Bennett E. W. , Muir S. E. St J.
Published: July 2012

Summary

A programme of tests was undertaken of concrete prisms in axial compression to study the influence of the static strength and the maximum size of coarse aggregate upon the fatigue strength at one million cycles. Four types of concrete were tested having average static strengths of about 6,000 and 8,500 lb/in2, each made with aggregate of ¾ and ⅜ in. maximum size. The fatigue strength varied between 66 and 71 % of the static strength and, although the percentage values were significantly lower with the higher-strength concrete and with the ⅜ in. aggregate, the actual magnitude of the differences was small. The general strain history was typical of previous fatigue tests, and the ‘run-out’ specimens showed a marked increase in static strength over similar specimens that had not been loaded.
Creep of concrete under uniaxial and biaxial stresses at elevated temperatures
Authors: Arthanari S. , Yu C. W.
Published: July 2012

Summary

This paper deals briefly with the need for data on creep and shrinkage of concrete at elevated temperatures. Tests designed to determine the Poisson's effect under combined stresses on heated concrete are described and it is shown that an effective Poisson's ratio of 0·2 can be assumed for design purposes. General conclusions regarding creep at elevated temperatures have been drawn from tests on sealed and unsealed slab specimens at elevated temperatures.
3D numerical simulation of local scouring under hydrographs
Authors: Dehghani Amir Ahmad , Esmaeili Taymaz , Chang Wen-Yi , Dehghani Navid
Published: July 2012

Owing to the interaction between three-dimensional (3D) flow pattern and bed material, the process of local scouring around bridge piers is complex. Simply using the empirical scour formula may be insufficient for the evaluation of pier scour under the unsteady flow condition. In the present study, the evolution of scour depth under unsteady flow has been simulated using a 3D numerical model. The model solves 3D Navier–Stokes equations incorporated with the sediment continuity equation to take into account the interaction between flow and sediment. The simulated scour-depth evolution coincides with the measured one quite well under the steady flow condition. For the unsteady hydrograph, a compounded method is proposed for simulations of scour-depth evolution as well as for scour hole development. The results show the simulated bed elevation contours are in good agreement in front of the pier, while the simulated final scour depth is slightly lower than the measured data by 15%. In addition, it is found that the simulated scour depth at the end of the rising limb is 74–79% of the final scour depth, which implies that the recession period of the hydrograph plays a less effective role than the rising limb in the unsteady scouring process.
Equations for critical and normal depths of city-gate sections
Authors: Liu Jiliang , Wang Zhengzhong
Published: July 2012

Critical and normal depths are two important parameters in the design of open channels and the analysis of varied flow. For many practical sections, the governing equations for critical and normal depths are implicit and no analytical solutions exist. Various explicit equations have been developed for common open-channel sections. However, there are very limited studies on calculations of critical and normal depths for the city-gate section (CGS), which is one of the frequently used cross-sections for free-water conveyance tunnels. This paper presents equations for the geometric elements of standard CGSs used in water conveyance systems such as for irrigation, drainage and water supply projects. Based on the principle of gradual optimisation fitting, explicit equations for normal and critical depths of standard CGSs were developed for manual calculations with maximum relative errors of less than 1%. The proposed equations have a high accuracy for use in hydraulic design.
Briefing: Energy from waste, finally coming of age?
Authors: Chilton Malcolm
Published: July 2012

The UK coalition government’s review of waste policy in England was published in June 2011, after a year of deliberation. To the disappointment of many commentators it did not embrace ambitious new targets or set out a definitive road map for attaining existing ones. Instead, it gave a cautious assessment of how existing mandatory obligations might be met. In doing so, the review recognised the primacy of the waste hierarchy in guiding decision making. However, it emphasised that the statutory basis for the hierarchy permits a significant degree of flexibility to reflect social, economic and environmental considerations. This is especially pertinent at the boundary between recycling and recovery, where various cost, environmental and social considerations around energy and climate change may tilt the balance in favour of energy recovery. This briefing explores the dynamics of this interpretation of the waste hierarchy and its implications for energy from waste development in future.
The Impact of Oral Health on the Academic Performance of Disadvantaged Children
Authors: Seirawan Hazem , Faust Sharon , Mulligan Roseann
Published: July 2012

Objectives. We measured the impact of dental diseases on the academic performance of disadvantaged children by sociodemographic characteristics and access to care determinants

Methods. We performed clinical dental examinations on 1495 disadvantaged elementary and high school students from Los Angeles County public schools. We matched data with academic achievement and attendance data provided by the school district and linked these to the child’s social determinants of oral health and the impact of oral health on the child’s school and the parents’ school or work absences.

Results. Students with toothaches were almost 4 times more likely to have a low grade point average. About 11% of students with inaccessible needed dental care missed school compared with 4% of those with access. Per 100 elementary and high school–aged children, 58 and 80 school hours, respectively, are missed annually. Parents averaged 2.5 absent days from work or school per year because of their children’s dental problems.

Conclusions. Oral health affects students’ academic performance. Studies are needed that unbundle the clinical, socioeconomic, and cultural challenges associated with this epidemic of dental disease in children.
Evidence in Oral Health Promotion—Implications for Oral Health Planning
Authors: Singh Shenuka
Published: July 2012

I have explored the debates on evidence-based oral health promotion and examined the practicality of promoting oral health care within a whole system (social, cultural, and environmental) approach.

The use of evidence-based decision-making in health services and planning is a viable mechanism to identify optimal health benefits; however, barriers to the effective adoption of evidence-based health practice, including barriers that apply to oral health promotion, have been identified.

Evidence-based oral health promotion highlights the importance of examining health promotion activities within a defined social context—a departure from the focus on improving study designs and research methods. Thus, the basis for evidence in health activities is grounded in social and organizational systems. This could contribute to sustainable health efforts.
Engaging Individuals Recently Released From Prison Into Primary Care: A Randomized Trial
Authors: Wang Emily A. , Hong Clemens S. , Shavit Shira , Sanders Ronald , Kessell Eric , Kushel Margot B.
Published: July 2012

Objectives. Individuals released from prison have high rates of chronic conditions but minimal engagement in primary care. We compared 2 interventions designed to improve primary care engagement and reduce acute care utilization: Transitions Clinic, a primary care–based care management program with a community health worker, versus expedited primary care.

Methods. We performed a randomized controlled trial from 2007 to 2009 among 200 recently released prisoners who had a chronic medical condition or were older than 50 years. We abstracted 12-month outcomes from an electronic repository available from the safety-net health care system. Main outcomes were (1) primary care utilization (2 or more visits to the assigned primary care clinic) and (2) emergency department (ED) utilization (the proportion of participants making any ED visit).

Results. Both groups had similar rates of primary care utilization (37.7% vs 47.1%; P = .18). Transitions Clinic participants had lower rates of ED utilization (25.5% vs 39.2%; P = .04).

Conclusions. Chronically ill patients leaving prison will engage in primary care if provided early access. The addition of a primary care–based care management program tailored for returning prisoners reduces ED utilization over expedited primary care.
Acid Treatment of Crushed Brick (from Central African Republic) and its Ability (After FeOOH Coating) to Adsorb Ferrous Ions from Aqueous
Solutions
Authors: C. Dehou S. , Wartel M. , Recourt P. , Revel B. , Boughriet A.
Published: July 2012

Brick made by craftsmen in Central African Republic was treated at 50°C and 90°C with a 6M solution of
hydrochloride acid for different time lengths. Total chemical compositions of leached samples were determined by ICPAES
and their chemical, mineralogical and morphological/textural properties were characterized by using an
environmental scanning electron microscope equipped with an energy dispersive X-ray spectrometer, 27Al solid-state
MAS NMR spectrometry, N2 adsorption - desorption (BET) method. The acid-modified brick was found to possess a
higher surface area as a result of structural and compositional collapses with significant Fe an Al losses which reached up
to 85 wt.% for Fe and 55 wt.% for Al. Pore size distributions had allowed us to show the predominance of mesoporous
structures with roughly two pore-diameter maxima at 7.6 nm and 14.6 nm. Higher surface acidity was also detected on
HCl-treated brick pellets, indicating the generation of Brönsted and/or Lewis acid sites on their surfaces; These acid
centers were evidenced by 1H-MAS NMR spectrometry and also by FT-IR using pyridine as a probe molecule. The
quantification of these acid sites was performed firstly by pHmetry with a NaOH solution under a strictly controlled N2
atmosphere, and secondly by adsorption - desorption studies of pyridine versus temperature using ThermoGravimetric
(TGA)/Differential Thermal (DTA) analyses and TGA coupled to Mass spectrometry. The acid treatment of brick led to a
higher surface area mesoporous material that was used in the present work as an adsorbent for removing Fe2+ ions from
aqueous solutions after deposition of iron oxy-hydroxides. The efficiency of this new composite was confirmed in the
laboratory by carrying out fixed-bed column experiments.
Prescription Patterns and Mineral Metabolism Abnormalities in the Cinacalcet Era
Authors: Fukagawa Masafumi , Fukuma Shingo , Onishi Yoshihiro , Yamaguchi Takuhiro , Hasegawa Takeshi , Akizawa Tadao , Kurokawa Kiyoshi , Fukuhara Shunichi
Published: July 2012

Background and objectives

Prescription patterns for hemodialysis patients with secondary hyperparathyroidism have varied widely since market introduction of cinacalcet. This study examined associations between prescription patterns and subsequent laboratory values.

Design, setting, participants, & measurements

Using a Mineral and Bone Disorder Outcomes Study for Japanese CKD Stage 5D Patients subcohort, 1716 prevalent hemodialysis patients (4048 sets for repeated measures between January 2008 and July 2009) with an intact parathyroid hormone (iPTH) level >180 pg/ml who used intravenous vitamin D receptor activator (VDRA) without cinacalcet were selected. Prescription patterns were defined based on cinacalcet administration (starting or not) and VDRA dosage change (decreased [<−25%], stable [−25% to 25%], or increased [>25%]). Proportion differences (PDs) were determined for decreasing iPTH levels by at least one category (<180, 180–299, 300–499, and ≥500 pg/ml) and for achieving target phosphorus (3.5–6.0 mg/dl) and calcium (8.4–10.0 mg/dl) levels, adjusting for potential confounders.

Results

The starting cinacalcet and increased VDRA patterns were associated with decreasing iPTH levels (PD, 0.25 and 0.13; 95% confidence intervals [95% CIs], 0.19–0.31 and 0.09–0.17, respectively); combination use had an additive association (PD, 0.34; 95% CI, 0.20–0.42). The starting cinacalcet and decreased VDRA combination was associated with simultaneously achieving target phosphorus (PD, 0.12; 95% CI: 0.04–0.20) and calcium (PD, 0.09; 95% CI, 0.01–0.17) levels.

Conclusions

Certain combinations of cinacalcet and VDRA were associated with decreasing iPTH and achieving targets for phosphorus and calcium. Combinations may prove advantageous versus VDRA alone in managing secondary hyperparathyroidism.
Hyperbolic normal forms and invariant manifolds: Astronomical applications
Authors: Efthymiopoulos C.
Published: July 2012

In recent years, the study of the dynamics induced by the invariant manifolds
of unstable periodic orbits in nonlinear Hamiltonian dynamical systems has
led to a number of applications in celestial mechanics and dynamical
astronomy. Two applications of main current interest are i) space manifold
dynamics, i.e. the use of the manifolds in space mission design, and, in a
quite different context, ii) the study of spiral structure in galaxies. At
present, most approaches to the computation of orbits associated with
manifold dynamics (i.e. periodic or asymptotic orbits) rely either on the use
of the so-called Poincar? - Lindstedt method, or on purely numerical methods.
In the present article we briefly review an analytic method of computation of
invariant manifolds, first introduced by Moser (1958), and developed in the
canonical framework by Giorgilli (2001). We use a simple example to
demonstrate how hyperbolic normal form computations can be performed, and we
refer to the analytic continuation method of Ozorio de Almeida and
co-workers, by which we can considerably extend the initial domain of
convergence of Moser?s normal form.
Multifrequency radio observations of SNR J0536-6735 (N 59B) with associated pulsar
Authors: Bozzetto L.M. , Filipovic M.D. , Crawford E.J. , de Horta , Stupar M.
Published: July 2012

We present a study of new Australian Telescope Compact Array (ATCA)
observations of supernova remnant, SNR J0536-6735. This remnant appears to
follow a shell morphology with a diameter of D=36x29 pc (with 1 pc
uncertainty in each direction). There is an embedded HII region on the
northern limb of the remnant which made various analysis and measurements
(such as flux density, spectral index and polarisation) difficult. The
radio-continuum emission followed the same structure as the optical emission,
allowing for extent and flux density estimates at 20 cm. We estimate the
surface brightness at 1 GHz of 2.55x10?21 Wm?2 Hz?1 sr?1 for the SNR. Also,
we detect a distinctive radio-continuum point source which confirms the
previous suggestion of this remnant being associated with pulsar wind nebula
(PWN). The tail of this remnant is not seen in the radio-continuum images and
is only seen in the optical and X-ray images.
An investigation of mass composition of ultra-high energy cosmic rays with energies above 1019 eV via the study of extensive air showers
Authors: Doostmohammadi S. , Fatemi S.J.
Published: July 2012

The electron and muon components of extensive air shower (EAS) with energies
above 1019 eV are analyzed via various giant EAS arrays. A varying property
of showers is observed for two energy ranges; higher and lower than (3 ? 4) x
1019 eV. The age parameter, zenith angle, shower size dependence on muon size
and shower size dependence on primary energy show an increment of mass
composition (MC) above (3?4)x 1019eV. Comparison of the observed EAS results
with the simulations of Capdevielle et al. (2000) and Shinozaki et al. (2005)
gives at most 20% photon fraction for primary energies above 1019 eV. The
arrival directions of showers above 4x1019 eV indicate an increasing
concentration towards the super galactic plane.
Maximum mass ratio of am CVn-type binary systems and maximum white dwarf mass in ultra-compact x-ray binaries (addendum - Serb. Astron. J. No. 183 (2011), 63)
Authors: Arbutina B.
Published: July 2012

We recalculated the maximum white dwarf mass in ultra-compact X-ray binaries
obtained in an earlier paper (Arbutina 2011), by taking the effects of
super-Eddington accretion rate on the stability of mass transfer into
account. It is found that, although the value formally remains the same
(under the assumed approximations), for white dwarf masses M2 >~0.1MCh mass
ratios are extremely low, implying that the result for Mmax is likely to have
little if any practical relevance.
Continuing Disparities in Cardiovascular Risk Factors and Complications Between Aboriginal and Anglo-Celt Australians With Type 2 Diabetes
Authors: Davis Timothy M.E. , Hunt Kerry , McAullay Daniel , Chubb Stephen A.P. , Sillars Brett A. , Bruce David G. , Davis Wendy A.
Published: July 2012

OBJECTIVE

To determine whether disparities in the nature and management of type 2 diabetes persist between Aboriginal and the majority Anglo-Celt patients in an urban Australian community.

RESEARCH DESIGN AND METHODS

Baseline data from the observational Fremantle Diabetes Study collected from 1993 to 1996 (phase I) and from 2008 to 2011 (phase II) were analyzed. Patients characterized as Aboriginal or Anglo-Celt by self-report and supporting data underwent comprehensive assessment, including questionnaires, examination, and biochemical testing in a single laboratory. Generalized linear modeling with age/sex adjustment was used to examine differences in changes in variables in the two groups between phases I and II.

RESULTS

The indigenous participants were younger at entry and at diabetes diagnosis than the Anglo-Celt participants in both phases. They were also less likely to be educated beyond primary level and were more likely to be smokers. HbA1c decreased in both groups over time (Aboriginal median 9.6% [interquartile range 7.8–10.7%] to 8.4% [6.6–10.6%] vs. Anglo-Celt median 7.1% [6.2–8.4%] to 6.7% [6.2–7.5%]), but the gap persisted (P = 0.65 for difference between phases I and II by ethnic group). Aboriginal patients were more likely to have microvascular disease in both phases. The prevalence of peripheral arterial disease (ankle-brachial index ≤0.90 or lower-extremity amputation) increased in Aboriginal but decreased in Anglo-Celt participants (15.8–29.7 vs. 30.7–21.5%; P = 0.055).

CONCLUSIONS

Diabetes management has improved for Aboriginal and Anglo-Celt Australian patients, but disparities in cardiovascular risk factors and complications persist.
Complexation of some univalent organic cations with benzo-18-crown-6 in nitrobenzene saturated with water
Authors: Makrlík Emanuel , Vaňura Petr , Selucký Pavel
Published: July 2012

From extraction experiments and γ-activity measurements, the exchange extraction constants corresponding to the general equilibrium C+(aq) + 1·Na+(nb) 1·C+ (nb) + Na+(aq) taking place in the two-phase water-nitrobenzene system (C+ = methylammonium, ethylammonium, propylammonium, ethanolammonium, diethanolammonium, triethanolammonium, cation TRIS+, hydrazinium, hydroxylammonium; 1 = benzo-18-crown-6; aq = aqueous phase, nb = nitrobenzene phase) were evaluated. Furthermore, the stability constants of the 1·C+ cationic complex species in nitrobenzene saturated with water were calculated; they were found to increase in the following cation order: triethanolammonium +
A direct method for the decontamination of a fly ash amended wet soil, artificially polluted with dioxins
Authors: Simion Alina , Kakeda Mitsunori , Egashira Naoyoshi , Mitoma Yoshiharu , Simion Cristian
Published: July 2012

We report hereby the first method of direct treatment of a wet soil containing toxic polychloroderivatives. Using a system with metallic Ca and 5% Rh fixed on charcoal in methanol, soil samples artificially polluted with fly ash containing polychloro-dibenzodioxins (PCDDs), polychloro-dibenzofurans (PCDFs) and coplanar polychlorinated biphenyls (co-PCBs), and having 69.2% to 84.6% moisture content, were successfully treated and decontaminated. This treatment afforded excellent hydrodechlorination yields for the 29 most toxic congeners of PCDDs, PCDFs and PCBs (98.3% degradation yield based on toxic equivalent quotient — or TEQ) after a 24 h treatment, at room temperature.
Synthesis, characterization and adsorption properties of nanostructured hybrid materials modified by boron and zirconium
Authors: Georgieva Ralitsa , Vassileva Paunka , Detcheva Albena , Voykova Dimitrinka , Gerganova Tsvetelina , Ivanova Yordanka
Published: July 2012

The adsorption properties of two new nanostructured hybrid materials containing B2O3 and ZrO2 were studied. The new organic-inorganic materials were synthesized via a sol-gel method. As a modifying agent, a quantity of 10 wt.% Zr(OPr)4 or B(OCH3)3 was added. The structure of the hybrid materials was investigated by means of (Fourier transform infrared spectroscopy (FTIR), x-ray diffractometry (XRD), scanning electron microscopy (SEM), (atomic force microscopy (AFM) and nuclear magnetic resonance spectroscopy (NMR). Based on the obtained data, the most probable cross-linking mechanism for the derived gels was proposed. The characterization of texture parameters of both materials was carried out with the use of low-temperature adsorption of nitrogen. Adsorption of Cu(II), Fe(III), Cr(III), Cd(II) and Pb(II) ions on both materials was investigated using multi-component solutions with different concentrations and acidity by means of the batch method. Kinetics of adsorption was also investigated. Pseudo-first order, pseudo-second order and intraparticle diffusion models were used to analyze kinetic data. The adsorption was significantly affected by the pH value. Equilibrium data were fitted to linear Langmuir, Freundlich and Dubinin-Radushkevich models and maximum adsorption capacities were calculated.
Conformational isomerism of 1-butene secondary ozonide as studied by means of matrix isolation infrared absorption spectroscopy
Authors: Strazdaite Simona , Bariseviciute Ruta , Ceponkus Justinas , Sablinskas Valdas
Published: July 2012

Theoretical calculations of structures, stability and vibrational spectra of 1-butene secondary ozonide (SOZ) conformers were performed using DFT method B3LYP with a 6-311++G(3df, 3pd) basis set. The calculations predict six staggered structures of 1-butene SOZ. The FTIR spectra of 1-butene SOZ isolated in Ar, N2 and Xe matrices were recorded. It was found that nitrogen is the best suited for the matrix isolation of 1-butene SOZ. The bandwidth of the spectral bands of the ozonide isolated in nitrogen was as narrow as 2 cm−1. For the first time the existence of five conformers of 1-butene SOZ were confirmed experimentally by means of matrix isolation infrared absorption spectroscopy. The equatorial gauche (∠OCCC=−66.1°) conformer was proved theoretically and experimentally to be the most stable. It was found that due to high potential barriers of the conformational transitions annealing of the matrix is useless for the assignment of spectral bands to various conformers of 1-butene SOZ. Using the hot nozzle technique the van’t Hoff experimental plots were made for three additional conformers of 1-butene SOZ and experimental ΔH values for these additional conformers were established. The crystallization problems of 1-butene SOZ are discussed which accounts for the rich conformational diversity of the ozonide as well as high conformational barriers for axial-equatorial transitions.
Synthesis of fluorescent carboxylic acid ligands for construction of monolayers on nanostructures
Authors: Jadhav Sushilkumar
Published: July 2012

Two new long-chain carboxylic acids (1, 2) bearing strong fluorescent group pyrene as ligands for Self-Assembled Monolayers (SAMs) have been synthesized. The multistep targeted synthesis is accomplished by use of Pyren-1-yl methylamine hydrochloride and employing simplified synthetic protocols. Compound 2 contains a chiral center purposely introduced along the atom chain in order to make it suitable for chiro-optical studies of the resulting SAMs.
Synthesis and acid solution properties of a novel betaine zwitterionic surfactant
Authors: Quan Hongping , Zhang Xuan , Lu Hongsheng , Huang Zhiyu
Published: July 2012

An effective and economic route was developed to synthesize a novel betaine zwitterionic surfactant gondoyl dimethyl amidopropyl betaine (GDAB) directly from natural fatty acid gondoic acid. The optimal processing conditions for synthesizing the intermediate and final product were probed: N,N-dimethyl-N′-gondoyl-1,3-propylenediamine was synthesized by the reaction of gondoic acid with N,N-dimethyl-1,3-propylenediamine at 160°C for 6 h, then the intermediate was reacted with sodium chloroacetate in methanol-water system (methanol/water:20% at 60°C and the product was obtained after 6h. The compounds were confirmed by IR and 1HNMR. The properties of GDAB acid solution were investigated and the results indicated that viscosity of acid solution increased with decreasing hydrochloric acid concentration and was mainly controlled by surfactant concentration and temperature. The viscosity of acid solution reached the maximum value when the concentration of hydrochloric acid was 2.28 mo L−1.
Isocratic liquid chromatographic determination of three paraben preservatives in hygiene wipes using a reversed phase core-shell narrow-bore column
Authors: Tzanavaras Paraskevas , Karakosta Theano , Rigas Pantelis , Themelis Demetrius , Zotou Anastasia
Published: July 2012

The first HPLC method for the separation of three paraben preservatives (methyl-, ethyl- and propyl parabens) using a core-shell analytical column is reported in this study. The separation was completed in less than 8 min at a low flow rate of 0.4 mL min−1 and an isocratic mobile phase containing 20% acetonitrile as organic modifier. The backpressure was HPLC equipment. The proposed analytical procedure was validated for linearity (0.5–20 µg L−1), limits of detection (15–43 µg L−1) and quantification (50–142 µg L−1), selectivity, within day (1.3–1.5%) and day-to-day (3.4–4.6%) precision and accuracy. The proposed method has been applied to the determination of the selected paraben preservatives in commercially available hygiene wipes. The mean percent recoveries were found to be in the range of 98.0–98.4%.
Voltammetric determination of Rutin at Screen-Printed carbon disposable electrodes
Authors: Oliveira-Roberth Aline , Santos Diego , Cordeiro Diogo , Lino Fernando , Bara Maria , Gil Eric
Published: July 2012

Rutin is a flavonoid commonly employed for many therapeutic purposes. Although the electroactive phenolic groups of rutin might be oxidized at low applied potential, the adsorption of oxidized species changes the electrode surface. As a consequence, the repeatability and reproducibility of the method decreases, which limits electroanalytical applications. This paper describes the use of disposable screen-printed electrodes as an alternative to improve the electrochemical quantification of rutin in commercial and standard samples. The electrochemical behavior was consistent to what is observed using other carbon electrodes: an adsorption-involved step and a pH-dependent oxidation process. The replacement of the electrodes between the analyses ensured rapid analysis, good intermediate precision and repeatability. The proposed method was successfully applied to rutin determination in pharmaceutical samples of capsules, with the limit of quantification being 0.30 µM.
Selected risk factors of fractures in children — own observation
Authors: Jakubowska-Pietkiewicz Elżbieta , Fendler Wojciech , Młynarski Wojciech , Klich Izabela , Chlebna-Sokół Danuta
Published: July 2012

Bone fractures may depend on Vitamin D Receptor Gene (VDR), bone mineral density, bone turnover markers. Patients and methods. 161 patients were recruited and underwent: skeletal densitometry (DXA) method and bone turnover studies (Osteocalcin and Ntx).The study group was evaluated using restriction enzyme digestion at BsmI (rs1544410), FokI (rs2228570), ApaI (rs7975232) and TaqI (rs731236), polymorphic sites of the VDR gene. Multivariate logistic regression was used to assess factor significance. The model included variables with sex- and age-standardized parameters, VDR genotypes, and bone metabolism marker levels. Results. Factors associated with fractures were: osteocalcin concentration and Z-score BMDt. Odds Ratio (OR) values equaled: 1.01 (95%Confidence Interval (95%CI) 1.00–1.02) for osteocalcin (p=0.006), and 0.66 (95%CI 0.42-1.03; p=0.07) for Z-score BMDt. In patients with reduced bone mass, factors related to fractures were: osteocalcin (0.04) and carriage of BsmI b (0.07) or ApaI a alleles (0.08). ORs were 1.01 (95%CI 1.00–1.02) for OC, 0.29 (95%CI 0.07–1.14) for BsmI, and 2.13 (95%CI 0.91–4.99) for ApaI polymorphic allele carriage. Conclusions. Carriage of BsmI b allele reduces, while carriage of ApaI a allele and heightened osteoclacin level increase the risk of fractures in study children with reduced bone mass. VDR polymorphism, bone mineral density and bone formation’s marker — osteocalcin maybe considered as risk factor for fracure in children from Lodz region.
Occurrence of Fusarium species in maize grains for silage
Authors: Krnjaja Vesna , Lević Jelena , Stanković Slavica , Bijelić Zorica
Published: July 2012

Occurrence of Fusarium species in maize grains for silage

Grain samples of two maize hybrids, medium early (ZP434) and late maturity (ZP704), collected during harvest in 2008 were investigated for contamination by fungi. Grains were plated on agar media and grown fungi were identified by morphological macroscopic and microscopic characteristics on potato-dextrose agar (PDA) and synthetic nutrient agar (SNA). Species of the genus Fusarium were the most common in both hybrids, and their presence amounted to 33.89% (ZP434) and 42.00% (ZP704). Other fungi of genera, Acremonium, Alternaria, Aspergillus, Chaetomium, Cladosporium, Nigrospora, Penicillium, Rhizopus and Trichotecium, were isolated from 0 to 41.00%. Four species belonging to the genus Fusarium were identified, of which the species F. verticillioides was the most common with 28.63% in ZP434 and 30.50% in ZP704 hybrids. The presence of F. graminearum, F. proliferatum and F. subglutinans ranged from 3.00% (ZP704) to 5.00% (ZP434), 0.13% (ZP434) to 7.00% (ZP704) and 0.13% (ZP434) to 7.00% (ZP704), respectively. Generally, the incidence of every particular fungus was higher in the late maize hybrid with a higher moisture content than in the medium-early hybrid with a lower moisture content.
Intracranial pediatric aneurysms: endovascular treatment and its outcome
Authors: Saraf Rashmi , Shrivastava Manish , Siddhartha Wuppalapati , Limaye Uday
Published: July 2012

Object

The aim of this study was to analyze the location, clinical presentation, and morphological characteristics of pediatric aneurysms and the safety, feasibility, and durability of endovascular treatment.

Methods

The authors conducted a retrospective study of all cases involving patients 18 years old or younger who underwent endovascular treatment for pediatric aneurysms at their institution between July 1998 and July 2010. The clinical presentation, aneurysm location, endovascular management, and treatment outcome were studied.

Results

During the study period, 23 pediatric patients (mean age 13 years, range 2 months–18 years) were referred to the authors' department and underwent endovascular treatment for aneurysms. The aneurysms were saccular in 6 cases, dissecting in 4, infectious in 5, and giant partially thrombosed lesions in 8. Fourteen of the aneurysms were ruptured, and 9 were unruptured. Thirteen were in the anterior circulation and 10 in the posterior circulation. The most common location in the anterior circulation was the anterior communicating artery; in the posterior circulation, the most common location was the basilar artery. Saccular aneurysms were the most common type in the anterior circulation; and giant partially thrombosed and dissecting aneurysms were the most common types in the posterior circulation. Coil embolization was performed in 7 cases, parent vessel sacrifice in 10, flow reversal in 3, glue embolization in 2, and stent placement in 1. Immediate angiographic cure was seen in 21 (91%) of 23 patients. Complications occurred in 4 patients, 3 of whom eventually had a good outcome. No patient died. Overall, a favorable outcome was seen in 22 (96%) of 23 patients. Follow-up showed stable occlusion of aneurysms in 96% of the patients.

Conclusions

Pediatric aneurysms are rare. Their clinical presentation varies from intracranial hemorrhage to mass effect. They may also be found incidentally. Among pediatric patients with aneurysms, giant aneurysms are relatively common. Endovascular management is associated with low rates of complications and is a safe, durable, and effective treatment for pediatric aneurysms.
Comparison of 5-year outcomes between pedicle screw and hybrid constructs in adolescent idiopathic scoliosis
Authors: Hwang Steven W. , Samdani Amer F. , Wormser Ben , Amin Hari , Kimball Jeff S. , Ames Robert J. , Rothkrug Alexander S. , Cahill Patrick J.
Published: July 2012

Object

Pedicle screw fixation has been theorized to provide better correction of scoliotic deformity, but controversy over the benefits of pedicle screw–only constructs remains, and the longer-term impact of pedicle screw fixation as compared with hybrid constructs is unclear. In this study, a retrospective review of a prospectively collected database was conducted to determine the longer-term impact of pedicle screw fixation as compared with hybrid constructs in patients with adolescent idiopathic scoliosis (AIS).

Methods

The authors retrospectively reviewed a multicenter database of pediatric patients (ages ≤ 18) from 1995 to 2006 and identified 127 patients with Lenke Type 1–4 AIS curves with a minimum 5 years of follow-up. Patients were divided into 2 cohorts based on whether they had undergone pedicle screw fixation or fixation with hybrid constructs.

Results

The mean main thoracic curvature of 56.1° ± 13.0°, which corrected to 14.9° ± 9.3°, translated into a mean correction of 73% (p < 0.01). The curve was 19.4° ± 10.6° at 2-year follow-up and 20.5° ± 10.4° at 5 years. When comparing preoperative parameters between the groups, differences were noted in the magnitude of the main thoracic curve (p = 0.04), flexibility of the main thoracic curve (p = 0.02), coronal balance (p = 0.04), T2–12 kyphosis (p = 0.02), and sex (p = 0.02). The pedicle screw cohort had fewer spinal segments instrumented (p < 0.01), fewer anterior releases performed (p = 0.02), and fewer thoracoplasties performed (p < 0.01). By 5 years of follow-up, significant differences were apparent between the two cohorts with respect to upper thoracic curvature (p = 0.01), T2–12 (p = 0.02) and T5–12 (p = 0.02) kyphosis, lumbar lordosis (p < 0.01), and sagittal balance (p = 0.01).

Conclusions

Although some preoperative differences did exist, outcomes were comparable between hybrid and screw constructs at 2 and 5 years. However, hybrid constructs required more concurrent anterior releases and thoracoplasties to achieve similar results.
Pharmacokinetics and Tissue Distribution Study of Praeruptorin D from Radix Peucedani in Rats by High-Performance Liquid Chromatography (HPLC)
Authors: Liang Taigang , Yue Wenyan , Du Xue , Ren Luhui , Li Qingshan
Published: July 2012

Praeruptorin D (PD), a major pyranocoumarin isolated from Radix Peucedani, exhibited antitumor and anti-inflammatory activities. The aim of this study was to investigate the pharmacokinetics and tissue distribution of PD in rats following intravenous (i.v.) administration. The levels of PD in plasma and tissues were measured by a simple and sensitive reversed-phase high-performance liquid chromatography (HPLC) method. The biosamples were treated by liquid-liquid extraction (LLE) with methyl tert-butyl ether (MTBE) and osthole was used as the internal standard (IS). The chromatographic separation was accomplished on a reversed-phase C18 column using methanol-water (75:25, v/v) as mobile phase at a flow rate of 0.8 mL/min and ultraviolet detection wave length was set at 323 nm. The results demonstrate that this method has excellent specificity, linearity, precision, accuracy and recovery. The pharmacokinetic study found that PD fitted well into a two-compartment model with a fast distribution phase and a relative slow elimination phase. Tissue distribution showed that the highest concentration was observed in the lung, followed by heart, liver and kidney. Furthermore, PD can also be detected in the brain, which indicated that PD could cross the blood-brain barrier after i.v. administration.
À l'épreuve de la sexualité de l'enfant
Authors: Yi Mi-Kyung
Published: July 2012

Que se passe-t-il quand le savoir et le discours de l’adulte, parents, éducateur ou psychanalyste, se confrontent à l’épreuve de la sexualité de l’enfant ? Voici quelques éléments de réponse et d’interrogation esquissés en trois volets qui sont autant de mouvements de la sexualité infantile chez l’adulte mis en route et aussi en déroute par la confrontation à l’« enfant-question ».
Influence des projections parentales sur le développement sexuel de l'enfant
Authors: Robert-Ouvray Suzanne
Published: July 2012

La sexualité de l’enfant s’inscrit dans le champ développemental complexe de la psychomotricité. Les tensions corporelles, les sensations, les émotions et les premières images de soi et d’autrui sont liées aux gestes et aux paroles des parents. En mettant les mains et des mots sur le corps du bébé et du jeune enfant, le parent fait passer des informations sur sa propre sexualité, sur un mode vibratoire tonique et sensoriel. La sexualité de l’enfant se trouve ainsi conditionnée par les projections parentales.
Entre dénomination et catégorisation : la signalétique
Authors: Bosredon Bernard
Published: July 2012

De quoi la dénomination est-elle le nom ? Cet article se propose de revenir sur l’homonymie du terme dénomination qui renvoie aussi bien à des dénominations de classes qu’à des dénominations d’entités uniques. Si l’on adopte une perspective d’analyse moins morphosyntaxique et plus sémantiquement fonctionnelle, on peut dégager une modélisation de l’activité de nomination qui rend compte de la diversité formelle des dénominations monoréférentielles, qui associe étroitement des opérations spontanément conçues comme contradictoires – le classement des entités sous un même terme d’une part, la distinction d’un référent unique par son nom unique d’autre part – et qui, enfin, ancre dans l’historicité l’activité de nomination des locuteurs.
Pour un réexamen de la notion de dénomination
Authors: Petit Gérard
Published: July 2012

La notion de dénomination appartient au paysage de la sémantique lexicale, en France, depuis le début des années 80. Son implantation problématique est liée d’une part au contexte de sa réception et notamment à la prégnance du paradigme immanentiste dans la description linguistique. Un autre facteur important est le périmètre de la notion elle-même, telle qu’elle a été introduite. Nous montrerons que la dénomination caractérise une propriété sémiotique fondamentale du signe linguistique, mais qu’elle doit faire l’objet d’un réexamen pour donner la mesure de son efficience descriptive. Dans une première partie, nous reviendrons sur l’implicite théorique auquel cette notion est adossée et, notamment, sa relation avec le processus de lexicalisation. Une seconde partie proposera une approche modulaire de la dénomination sur la base de critères ontologiques, sociolinguistiques et vériconditionnels. L’objectif est de mettre en lumière l’étendue du champ d’application de la notion, laquelle fournit un puissant levier pour la description du lexique et des relations sémantiques.
De la dénomination à la désignation : le paradoxe ontologico-dénominatif des odeurs
Authors: Kleiber Georges
Published: July 2012

L’expression des odeurs représente un excellent observatoire pour voir comment s’articulent dénomination et désignation. Les odeurs passent en effet pour ne pas avoir de dénominations propres, l’affirmation revenant le plus souvent dans la littérature étant qu’« il n’y a pas de noms d’odeurs ». En va-t-il réellement ainsi ? Et si oui, comment s’effectue la saisie langagière des odeurs ? L’objectif de cet article est d’apporter, d’une part, des éléments de réponse à ces deux questions et, d’autre part, des éléments explicatifs nouveaux sur la problématique même que constitue le couple dénomination et désignation.
Gouvernance Internet : tensions actuelles et futurs possibles
Authors: de La Chapelle Bertrand
Published: July 2012

Internet est devenu un enjeu majeur des relations internationales. Le débat sur sa gouvernance oppose deux grandes logiques. L’une privilégie une gouvernance organisée autour des souverainetés nationales ou d’un multilatéralisme interétatique. L’autre, une approche multiacteurs, fait une large place à l’ensemble des acteurs des sociétés civiles. Une nouvelle gouvernance ne peut naître que du dépassement de débats simplistes reprenant les termes d’une « nouvelle guerre froide ».
Chine : Internet, levier de puissance nationale
Authors: Arsène Séverine
Published: July 2012

Internet fait désormais partie intégrante de la stratégie chinoise de développement et d’affirmation nationale. Mais cette stratégie suppose pour la Chine une souveraineté numérique, elle-même garantie par un contrôle de la gouvernance d’Internet. Pékin favorise donc l’hypothèse d’une gouvernance multilatérale interétatique dans le cadre de l’ONU, tout en adoptant dans les forums internationaux une position souple lui permettant de défendre tous ses intérêts, en particulier économiques.
Islam, nationalisme et vendetta: l'insurrection au Caucase du Nord
Authors: Souleimanov Emil
Published: July 2012

Au cours de la dernière décennie, l’insurrection qui faisait rage en Tchétchénie s’est répandue à d’autres régions du Caucase, en particulier au Daghestan et à l’Ingouchie. Le nationalisme laïque, porteur de possibles affrontements interethniques, a cédé la place au djihad comme principe unificateur de la lutte contre la Russie. D’autres facteurs viennent alimenter l’insurrection, notamment la coutume de la vendetta.