bluuebunny/crossref_metadata_2025 huggingface dataset:
Salt effect in hydrolysis of 3-acyl-1,3-diphenyltriazenes
Authors: Ludwig Miroslav , Pytela Oldřich , Večeřa Miroslav
Published: August 2011

Rate constants of non-catalyzed hydrolysis of 3-acetyl-1,3-diphenyltriazene (I) and 3-(N-methylcarbamoyl)-1,3-diphenyltriazene (II) have been measured in the presence of salts (ammonium chloride, potassium chloride, lithium chloride, sodium chloride and bromide, ammonium sulphate, potassium sulphate, lithium sulphate, sodium sulphate and zinc sulphate) within broad concentration ranges. Temperature dependence of the hydrolysis of the substrates studied has been measured in the presence of lithium sulphate within temperature range 20° to 55 °C. The results obtained have been interpreted by mechanisms of hydrolysis of the studied substances.
Study of keto-enol tautomerism and alkylation reactions of β-ketosulphones of 5-nitrofuran series
Authors: Jurášek Adolf , Polakovičová Dana , Kováč Jaroslav
Published: August 2011

2-(5-Nitro-2-furyl)-2-oxoethyl 3-X-phenyl sulphones I react with diazomethane in tetrahydrofuran or dioxane to give trisubstituted ethylenes II, i.e. 1-(5-nitro-2-furyl)-1-methoxy-2-(4-X-phenylsulphonyl)ethylenes (X = H, CH3, OCH3, N(CH3)2, Cl, NO2) which have Z configuration. From results of spectral and chemical investigation it follows that β-ketosulphones of 5-nitrofuran series only exist in ketoform and are very strong CH-acids (pKa 7.82-5.23). Alkylation of the sulphones I (X = H, CH3) with methyl iodide under conditions of extraction alkylation gives the corresponding C-methyl derivatives III. Interpretation is given of IR, UV, 13C and 1H NMR spectra of the sulphones I and II.
Tautomerism of 5-nitro-2-furylnitromethane
Authors: Sroková Iva , Vetešník Pavel , Jurášek Adolf , Kováč Jaroslav
Published: August 2011

UV study of properties of 5-nitro-2-furylnitromethane (I) in various solvents has shown that this compound is a very strong acid (pKa 3.98) forming an ion pair in protic solvents (water, alcohols) and existing exclusively as nitro-form in aprotic solvents (tetrachloromethane, chloroform, n-hexane, diethyl ether, dioxane). Kinetic study of tautomerism in water has given experimental values of combined rate constants of parallel reactions. Thermodynamic parameters of the tautomeric transformations have been calculated from temperature dependence of the rate constants.
Reactions of carbonyl isothiocyanates with enamines of the type CH3-C(NH2)=CH-X
Authors: Uher Michal , Ilavský Dušan , Foltín Jozef , Škvareninová Katarína
Published: August 2011

Reactions of carbonyl isothiocyanates with enamines of the type CH3-C(NH2)=CH-X (X = CN, COOC2H5, or COCH3) were investigated. The formation of products of AdN, SN, and cyclization reactions is discussed on the basis of their IR, UV and mass spectra. In one case, the thermal cyclization was followed by differential thermal analysis.
Preparation of aliphatic analogues of S-adenosyl-L-homocysteine and related compounds
Authors: Holý Antonín
Published: August 2011

Reaction of 9-((RS)-2,3-dihydroxypropyl)adenine (I) with p-toluenesulfonyl chloride afforded the 3-O-p-toluenesulfonyl derivative II which on treatment with 2,3-dihydropyran was transformed into the 3-O-p-toluenesulfonyl-2-O-tetrahydropyranyl derivative III. Reaction of II with sodium isobutyl mercaptide in liquid ammonia gave 9-((RS)-3-isobutylthio-2-hydroxypropyl)adenine (IV). Analogously, compound III and disodium salt of L-homocysteine after acid hydrolysis afforded S-((RS)-3-(adenin-9-yl)-2-hydroxypropyl)-L-homocysteine (V). 9-((2S,3S)-threo-2,3-O-Isopropylidene-4-O-p-toluenesulfonyl-2,3,4-trihydroxybutyl)adenine (VIII) was transformed in a similar way into the 4-isobutylthio derivative IX and the L-homocysteine derivative X. 9-Allyladenine (XII) on treatment with bromine in dioxane afforded 9-((RS)-2,3-dibromopropyl)adenine (XIII) and probably 3,9-(2-bromotrimethylene)adeninium bromide (XIV). Reaction of compounds XIII, XIV and 9-((RS)-2,3-bis-p-toluenesulfonyloxypropyl)adenine (XI) with sodium hydrogen sulfide or sodium thioacetate led invariably to polymeric compounds. 4-p-Toluenesulfonyloxymethyl-2,2-dimethyl-1,3-dithiolane (XVa) reacted with sodium salt of adenine to give 9-(X)-2,2-dimethyl-1,3-dithiolane-4-ylmethyl)adenine (XVIa); analogously, 4-p-toluenesulfonyloxymethyl-2-phenyl-1,3-dithiolane (XVb) afforded the 2,3-S-benzylidene derivative XVIb and 1-p-toluenesulfonyloxy-2,3-bis(benzylthio)propane (XIXb) gave 9-((RS)-2,3-bis(benzylthio)propyl)adenine (XIXc). Acetolysis of XVIa or reduction of XVIb with sodium in liquid ammonia led to 9-((RS)-2,3-dimercaptopropyl)adenine (XVIII) and the corresponding episulfide XVII.
Purification, characterization and mode of effect of another endo-D-galacturonanase from Aspergillus niger
Authors: Heinrichová Kvetoslava , Dzúrová Mária
Published: August 2011

A mixture of pectolytic enzymes was isolated from a commercial preparation of Pectinex Ultra. endo-D-Galacturonanase (EC 3.2.1.15) was obtained from this mixture of enzymes, produced by Aspergillus niger cultures, by affinity chromatography using cross-linked pectic acid as a support and by subsequent chromatography on a Sephadex G-100 column. One form of endo-D-galacturonanase only of approximate molecular weight of 35 000 was detected in the purified product by electrophoresis in polyacrylamide gel. The enzyme showed maximal activity and stability at pH 4.9 and 40°. The mode of degradation of a high molecular weight substrate and the per cent of the glycosidic bonds cleaved (6%) at a viscosity decrease by 50% indicate an endo type action pattern. endo-D-Galacturonanase was characterized by the mode of cleavage and the kinetic constants Km and V for oligogalacturonic acids and polygalacturonic acid. On the basis of the knowledge of the kinetic constants and the degradation products the mode of action of the enzyme and the extent of its active site are discussed.
Formation of sodium disulphite by reaction of solid sodium sulphite with gaseous sulphur dioxide
Authors: Vobiš Jiří , Mocek Karel , Erdös Emerich
Published: August 2011

The formation of sodium disulphite in a heterogeneous reaction between solid sodium sulphite and gaseous sulfur dioxide has been investigated in a fixed-bed reactor at temperatures from 40 up to 80 °C in the presence of water vapour. The partial pressure of the sulfur dioxide was in the range of 1.2 to 7.5 kPa and that of the water vapour amounted to 1.0-6.5 kPa. The study has been aimed at finding optimum conditions for the formation of the disulphite according to the final degree of conversion. It has been found that the final degree of conversion depends primarily on the content of water vapour in the gas phase and on the temperature, the reactivity of the sodium sulphite being significantly affected by the way of its preparation.
The polarography of neptunium in acetate medium
Authors: Niese Ursula
Published: August 2011

The behaviour has been investigated of neptunium on dropping mercury electrode and on hanging mercury drop in the presence and in the absence of uranium using acetate medium.
Self-cleaning rotating disc graphite electrode
Authors: Kulev I. I. , Stanev D. S.
Published: August 2011

The study offers a construction of a self-cleaning rotating disc graphite electrode (S.C.D.G.E.) applied for voltamperometric determinations and amperometric titrations hampered by passivations of electrode surface.
Refinement of the structure and properties of the N-salicylideneglycinato-thioureacopper(II) complex
Authors: Pavelčík František , Krätsmár-Šmogrovič Juraj , Švajlenová Oľga , Majer Jaroslav
Published: August 2011

The stable N-salicylideneglycinato-thioureacopper(II) complex crystallizes in the monoclinic system with a space group of C2/c (No 15); a = 1.8599 (11), b = 1.4275 (5), c = 1.3617 (6) nm; β = 138.64 (4)°, Z = 8. (R = 0.060). The Cu(II) coordination in this complex is approximately square-pyramidal. The pyramid base is formed by the O(1), N(1) and O(3) donor atoms of the Schiff base (salalgly) and the S-atom of the thiourea (tu); Cu ##e S = 0.2273 (3) nm. The apex of the pyramid is formed by the O(3iv) atom, provided by two complex molecules, thus joined to form a dimer [Cu(salalgly)(tu)]2. The cryomagnetic properties of the complex in the interval 90-330 K obey the Curie-Weiss law. Its magnetic moment is practically temperature independent: μef = 1.82 ± 0.01 B.M. The polycrystalline sample of complex (X band, room temperature) exhibits the axial type of EPR spectrum with g ##k = 2.210, g ##l = 2.044, g = 2.099 (the Curie constant yields g = 2.101).
Reduction of mixed NiO-U3O8 oxides by hydrogen and the effect of gamma radiation on the process
Authors: Pospíšil Milan , Topinka Jan
Published: August 2011

The reduction of mixed NiO-U3O8 oxides of various composition by hydrogen was studied in the temperature range 350-590 °C using the thermogravimetric method. An addition of nickel oxide in the amount of few per cent increases the reduction rate of U3O8 and substantially decreases the initial temperature of its reduction. The reduction of pure U3O8 proceeds with a maximum and steeply decreasing rate in the region of the oxide composition U3O8 → UO2.59 and with a constant rate in the region UO2.59 → UO2.25. In the heterogeneous two-component system the reduction rate increases with the increasing content of nickel oxide. The reduction of the stoichiometric NiO is retarded by a small homophaseous addition of U3O8. Radiation oxidation of U4+ ions proceeds during the pre-irradiation of the samples with gamma radiation at a dose of 1 MGy and the reduction rate of samples with a surplus of U3O8 is decreased. With the increasing content of nickel oxide the negative effect of radiation is continuously changed into a positive effect (an increase of the reduction rate). The reduction kinetics of irradiated samples is in both homogeneous extreme regions of composition governed by the adsorption processes and in the heterogeneous region it depends on the radiation-induced defects with strongly temperature-dependent stability.
Application of tower bioreactors with forced circulation in biomass production
Authors: Kaštánek František , Zahradník Jindřich , Rychtera Mojmír , Kratochvíl Jan , Čermák Jan
Published: August 2011

Characteristic hydrodynamic parameters of three selected types of bubble-type column reactors with forced liquid circulation were studied experimentally. Application of these units for the fermentation process - production of fodder protein by continuous cultivation of Candida utilis yeast on the synthetic ethanol was tested. Two modifications of the column reactor with the ejector gas distributor and the bubble type tower reactor with the central tube and forced internal circulation of the gas-liquid dispersion were selected. Diameter of all three reactors used was 0.3 m. The volumetric mass transfer coefficient (kLa) and gas holdup (εG) were determined both for the standard water-air system and under actual fermentation process conditions. The effect of the inlet ethanol concentration and of the dilution rate on the cultivation characteristics was determined during the cultivation experiments. The obtained results have proved that the studied reactor types are suitable for fermentation. Equipment with the ejector gas distributor can be recommended even for processes with high requirements on the oxygen consumption, while by the proposed construction arrangement the undesired foam formation in the system was successfully eliminated.
ESR studies of alkyl aryl ketyl radicals
Authors: Kutejová-Maťašová Eva , Staško Andrej , Malík Ľubomír
Published: August 2011

Reactions of R1-substituted benzenecarboxylic acids (R1 = H, Me, Et, and t-Bu) with R2MgX (R2 = Et and n-Pr) in the presence of nickel produce ketyl radicals R1-Ar-CO.-R2. Average values of splitting constants of the protons in the aromatic nucleus are a2 = a6 = 0.48 mT, a4 = 0.53 mT, and a3, a5 < 0.12 mT. In some cases for R2 = n-Pr interaction of gamma protons is also observed with a2 = 0.04 mT. The investigated substituents R1, R2 have no marked influence on distribution of spin density of the unpaired electron.
Relation between the distribution of platinum, its dispersion, and activity of catalysts prepared by impregnation of activated carbon with chloroplatinic acid solutions
Authors: Machek Vladimír , Hanika Jiří , Sporka Karel , Růžička Vlastimil , Kunz Jiří
Published: August 2011

The effect was studied of the solvent of chloroplatinic acid used for impregnation of activated carbon on the distribution and dispersion of platinum and on the catalyst activity. Using different solvents, catalysts were prepared exhibiting either surface platinum distribution (water) or its uniform distribution (ketones). Catalysts with uniform platinum distribution displayed a better stability of the platinum dispersity against sintering. The catalyst activities in liquid phase hydrogenation of 1-octene and of nitrobenzene were related to the platinum dispersity; the results suggest that the hydrogenations of the two substrates are governed by different mechanisms.
Electrochemical oxidation of methylindoles
Authors: Janda Miroslav , Šrogl Jan , Holý Petr
Published: August 2011

Electrochemical oxidation of 1-methylindole (I), 1,3-dimethylindole (II) and 1,2-dimethylindole (III) on a platinum anode in methanol, containing ammonium bromide, was studied. A more profound oxidation as compared with benzofuran or benzothiophene derivatives is indicated by the obtained products: 1-methyl-2,2-bis(1-methylindol-3-yl)-3-indolinone (IV), 1,1'-dimethyl-Δ3,3-biindolin-2,2'-dione (V), 3,3-dibromo-1-methyl-2-indolinone (VI), 3,3,5-tribromo-1-methyl-2-indolinone (VII), 3-bromo-1-methyl-2,3-indoledione (VIII), 3-methoxy-1,3-dimethyl-2-indolinone (IX), 3-hydroxy-1,3-dimethyl-2-indolinone (X), 3,5-dibromo-1,3-dimethyl-2-indolinone (XI) and 3-bromo-1,2-dimethylindole (XII). The ratio of the products can be significantly influenced by the electrolysis conditions. The oxidation takes place in positions 2 and 3 of the indole molecule, the position 2 influencing decisively the oxidation path.
The character of the binding sites for ethanol and acetaldehyde in pea alcohol dehydrogenase
Authors: Leblová Sylva , Čeřovská Noemi
Published: August 2011

The inhibition measurements carried out with pea alcohol dehydrogenase (PADH) in the presence of acids, acid amides, and dimethyl sulfoxide show that the binding sites for ethanol and acetaldehyde are not identical. The binding site for ethanol lies in the hydrophobic domain of the PADH molecule as follows from the inhibitory action of acids: with the increasing hydrophobicity of the organic acid the inhibitory power also increases. The inhibitory effect of amides indicates that the binding site for acetaldehyde is most likely localized in the part of the enzyme molecule which is not hydrophobic. The difference in the binding sites for ethanol and acetaldehyde has been postulated before on the basis of the measurements with chloride ions, which inhibit the two substrates to different degrees, and on the basis of differences in pH-optima for ethanol oxidation and acetaldehyde reduction.
Sedentary behaviour in youth
Authors: Pate Russell R , Mitchell Jonathan A , Byun Wonwoo , Dowda Marsha
Published: August 2011

The purpose of this review is to describe the amount of time children spend in sedentary behaviour and to determine if there are specific factors that associate with sedentary behaviour in children. The following search terms were used to identify relevant articles: sedentary behaviour, inactivity, television, computer, video games, small screen, sitting, prevalence, patterns, correlates, factors and determinants. The databases used to conduct the search included PubMed, PsycINFO, ERIC (Education Resources Information Center) and Academic Search Premier. The studies reviewed were limited to those that sampled children (2–18 years), were written in English and used a measure of sedentary behaviour as the dependent variable. Several studies reported the time spent watching television or the proportion of children at or above a threshold for television viewing (eg, ≥3 h/day). Among the accelerometer studies included, the National Health and Nutrition Examination Survey is the largest and reported ∼6.1, 7.5 and 8.0 h/day mean sedentary time in children 6–11, 12–15 and 16–19 years old, respectively. Taken together, the existing literature across the world indicates a slightly higher level of sedentary behaviour in older children. Higher levels of sedentary behaviour were also reported in non-white children, children from lower socioeconomic status background and children from households with more access to televisions/computers. Lower levels of sedentary behaviour were reported in children whose parents have rules/limitations on screen time.
Determinants of physical activity and sedentary behaviour in young people: a review and quality synthesis of prospective studies
Authors: Uijtdewilligen Léonie , Nauta Joske , Singh Amika S , van Mechelen Willem , Twisk Jos W R , van der Horst Klazine , Chinapaw Mai J M
Published: August 2011

Objective The aim of this systematic review was to summarise and update the existing literature on determinants of physical activity and sedentary behaviour in young people, considering the methodological quality of the studies.

Methods

Prospective studies were identified from searches in PubMed and PsycINFO, from April 2004 through November 2010. The authors included studies investigating the association between determinants of overall physical (in)activity and/or sedentary behaviour in healthy children or adolescents. When a determinant was investigated for its association with physical (in)activity and sedentary behaviour assessed between ages of 4–12, or mean age ≤12, it was classified as ‘child determinant’. When a determinant was investigated for its association with physical activity and sedentary behaviour assessed between ages of 13–18 or mean age >12, it was classified as ‘adolescent determinant’. Included articles were scored on their methodological quality and a best-evidence synthesis was applied to summarise the results.

Results

The authors identified 30 papers, of which seven were of high methodological quality. Intention was found as a determinant of children's physical activity. Determinants of adolescents' physical activity were age (ie, older children were more active), ethnicity (ie, being of African–American descent determined being less physically active) and planning. The authors found insufficient evidence for determinants of sedentary behaviour.

Conclusion

Studies on determinants of physical activity and sedentary behaviour were in general of poor methodological quality. To develop long-term effective interventions that increase physical activity and decrease time spent in sedentary behaviours in young people, we need more high quality prospective evidence on the determinants of these behaviours.
Aerobic fitness and its relationship to sport, exercise training and habitual physical activity during youth
Authors: Armstrong Neil , Tomkinson Grant , Ekelund Ulf
Published: August 2011

Aim

To analyse aerobic fitness and its relationship with sport participation, exercise training and habitual physical activity (HPA) during youth.

Methods

Studies were located through computer searches of Medline, SPORT Discus and personal databases. Systematic reviews of time trends in aerobic fitness/performance, and exercise training and peak oxygen uptake (peak VO2) are reported.

Results

Peak VO2increases with age and maturation. Boys' peak VO2is higher than girls'. Despite data showing a decrease in performance test estimates of aerobic fitness there is no compelling evidence to suggest that young people have low levels of peak VO2or that it is declining over time. The primary time constant of the VO2kinetics response to moderate and heavy intensity exercise slows with age and the VO2kinetics response to heavy intensity exercise is faster in boys. There is a negative correlation between lactate threshold as a percentage of peak VO2and age but differences related to maturation or sex remain to be proven. Young athletes have higher peak VO2, a faster primary time constant and accumulate less blood lactate at the same relative exercise intensity than their untrained peers. Young people can increase their peak VO2through exercise training but a meaningful relationship between aerobic fitness and HPA has not been demonstrated.

Conclusions

During youth the responses of the components of aerobic fitness vary in relation to age, maturation and sex. Exercise training will enhance aerobic fitness but a relationship between young people's current HPA and aerobic fitness remains to be proven.
Fitness and health of children through sport: the context for action
Authors: Micheli Lyle , Mountjoy Margo , Engebretsen Lars , Hardman Ken , Kahlmeier Sonja , Lambert Estelle , Ljungqvist Arne , Matsudo Victor , McKay Heather , Sundberg Carl Johan
Published: August 2011

A growing body of scientific evidence indicates that the declining levels of physical activity and fitness in children and youth are associated with adverse impacts on their health, including rising levels of obesity, diabetes, heart disease, metabolic syndrome and increased risk of sports injury. In response, a number of governmental and non-governmental organisations have instituted programmes to promote health in children and youth through sports and physical activity. Many of these programmes have achieved success in increasing participation in sports and other forms of physical activity and, by extension, improving the health of these young people. These programmes have also been used successfully to enhance the lives of the young participants by means other than improving physical health.
Premedications for infliximab infusions do not impact the risk of acute adverse drug reactions
Authors: Ducharme James , Pelletier Cindy , Zacharias Ramesh
Published: August 2011

Objective

The purpose of this study was to identify the association of premedication with the adverse drug reaction (ADR) rate in infliximab infusions.

Design

A retrospective chart review of 684 patients who received 4077 infusions in a network of community clinics over 16.5 months. Data collected included age, weight, sex, diagnosis, dose, premedications and ADR information, which was coded for time of onset, severity and outcome.

Setting

Community infusion clinics located in Ontario, Canada.

Patients

Patients aged 12–91 years who receive regular infliximab infusions to treat their autoimmune condition, mainly either Crohn's disease or rheumatoid arthritis.

Main outcome measures

The number of infusions to the occurrence of an acute ADR by presence of premedication.

Results

ADRs are not significantly different (χ2(1, n=644, p=0.651)=0.204) between those who always received premedications and those who never did. When controlling for age, sex, weight and diagnosis, patients receiving premedications were just as likely to experience an ADR as patients who never received any (OR 1.1, 95% CI 0.7 to 1.9, p=0.5). When assessing the number of infusions to the occurrence of an ADR using the Kaplan–Meier method, no significant difference was found between the two groups.

Conclusions

The use of premedications is not associated with a decreased risk of ADR in patients receiving infliximab. This held true for patients who had never had an ADR prior to receiving premedications and while controlling for age, sex, weight and diagnosis.
Immunohistochemical expression of keratan sulfate: a possible diagnostic marker for carcinomas of the female genital tract
Authors: Miyamoto Tsutomu , Ishii Keiko , Asaka Ryouichi , Suzuki Akihisa , Takatsu Akiko , Kashima Hiroyasu , Shiozawa Tanri
Published: August 2011

Aims

The authors previously reported the expression of keratan sulfate (KS), a glycosaminoglycan, in the epithelium of normal and neoplastic endometria. The aim of this study was to evaluate its potential use as a diagnostic marker, and the expression of KS was investigated in other human epithelial tissues.

Methods

Expression was examined immunohistochemically using 102 samples of normal epithelia and 110 samples of carcinomas from the female genital tract (FGT; cervix, endometrium, ovary, fallopian tube), digestive organs (gastrointestinal tract, pancreas, liver), urinary tract, lung, mammary gland, thyroid and mesothelium.

Results

In normal tissues, KS was consistently detected in the FGT and ectopic endometrium (25/26), but was not found in the digestive organs (1/42) and urinary tract (0/6), and was only partly detected in the lung (7/10), mammary gland (3/9) and thyroid (4/4). In malignant tissues, KS was consistently observed in carcinomas of the endometrium, ovary and fallopian tube (29/32), and was partly detected in carcinomas of the lung, mammary gland, thyroid, pancreas and mesothelium, but was absent in carcinomas of the gastrointestinal tract (0/17), liver (0/5) and urinary tract (0/11). Among carcinomas of the FGT, digestive organs and urinary tract, KS positivity suggested the possibility of FGT carcinomas, with 79.5% (31/39) sensitivity and 92.9% (39/42) specificity.

Conclusions

KS is a potentially useful marker for the supportive diagnosis of the primary site of metastatic carcinomas or unknown primary carcinomas, especially in the abdominal cavity.
Performance of the Iris iQ®200 Elite analyser in the cell counting of serous effusion fluids and cerebrospinal drainage fluids
Authors: Goubard A , Marzouk M , Canoui-Poitrine F , Launay S , Le Thuaut A , Legrand P
Published: August 2011

Aims

Evaluation of the Iris iQ®200 Elite analyser, initially designed for urinary cell counting, for the analysis of biological fluids (serous effusion fluids and cerebrospinal drainage fluids) and comparison of its performance with that of the manual microscopic method.

Methods

Routine samples (ascite fluids, pleural fluids and cerebrospinal fluids) were evaluated in terms of red blood cells and nucleated elements using the iQ®200 analyser and the manual method. The authors compared the reliability, repeatability and speed of the two techniques. In addition, the authors assessed the contribution of two different sample dilution processes to the improvement of iQ®200 analyser cytological results.

Results

Very good agreements were found between the two methods and between the two sample dilution processes. Regarding the repeatability, the coefficients of variation obtained with the iQ200 were slightly higher than those obtained by the manual method. Besides, the difference in the speed of the two methods was not significantly different for series with <10 samples.

Conclusions

The Iris iQ®200 Elite analyser has allowed us to obtain reliable results, equivalent to that of the manual method, for cell enumeration in biological fluids. Although the speed of this instrument needs to be improved for larger series of samples, it enables standardised and objective cytological results to be obtained and represents an alternative to the usual manual microscopic method. Moreover, automation of such analyses permits saving of technician time.
Multimodality treatment of a ruptured grade IV posterior fossa arteriovenous malformation in a patient pregnant with twins: case report
Authors: Dashti Shervin R , Spalding Aaron C , Yao Tom L
Published: August 2011

Introduction

Brain arteriovenous malformations (AVM) account for a significant percentage of brain hemorrhages in pregnant patients. There is general consensus that ruptured AVMs in pregnant women should be managed based on neurosurgical rather than obstetric considerations. Since the risk of re-hemorrhage is significantly higher in the pregnant patient with a ruptured AVM, aggressive treatment during pregnancy must be considered if this can be accomplished with acceptable risk. Recent advances in endovascular technology have increased the potential for successful treatment of previously inoperable high-grade AVMs.

Case report

A 17-year-old woman pregnant with twins experienced sudden onset headache and became unresponsive at 20 weeks gestation. A CT scan of the head showed cerebellar hemorrhage and obstructive hydrocephalus. Cerebral angiography showed a 5.5 cm AVM in the cerebellar vermis with deep drainage for a Spetzler Martin grade IV classification. Extensive two-stage Onyx embolization with complete casting of the nidus was performed. The patient delivered healthy twin girls at 36 weeks gestation by a planned cesarean section. This was followed by surgical resection of the AVM 4 months later with minimal blood loss. A follow-up angiogram showed no evidence of AVM recurrence 3 months after surgical resection. Her balance was significantly improved and she walked unassisted. She had mild cerebellar speech. Her twin girls are progressing normally.

Conclusion

Extensive endovascular Onyx embolization is feasible in the setting of a ruptured high-grade AVM during pregnancy. The rationale for proceeding with treatment is the perceived higher likelihood of re-hemorrhage from such a lesion.
Successful Onyx embolization of life threatening traumatic posterior jugal artery fistula following mandibular fracture
Authors: Maioriello Anthony V , Stanley Douglas J , Ho Tang , Ashley William W
Published: August 2011

The mandible is one of the most frequently fractured bones of the face. However, vascular injuries associated with mandibular fractures are exceedingly rare. If they do occur, they usually involve branches of the internal maxillary artery. In this article, a unique case of delayed, life threatening oropharyngeal hemorrhage, secondary to traumatic fistula of the posterior jugal artery, is reported, that was successfully treated using a neuroendovascular Onyx embolization technique.
Exposure to tobacco smoke before and after a partial smoking ban in prison: indoor air quality measures
Authors: Ritter Catherine , Huynh Cong Khanh , Etter Jean-François , Elger Bernice S
Published: August 2011

Although exposure to secondhand smoke (SHS) is reportedly high in prison, few studies have measured this in the prison environment, and none have done so in Europe. We measured two indicators of SHS exposure (particulate matter PM10 and nicotine) in fixed locations before (2009) and after (2010) introduction of a partial smoking ban in a Swiss prison. Access to smoking cessation support was available to detainees throughout the study.

Objectives

To measure SHS before and after the introduction of a partial smoking ban.

Methods

Assessment of particulate matter PM10 (suspended microparticles of 10 μm) and nicotine in ambient air, collected by real-time aerosol monitor and nicotine monitoring devices.

Results

The authors observed a significant improvement of nicotine concentrations in the air after the introduction of the smoking ban (before: 7.0 μg/m3, after: 2.1 μg/m3, difference 4.9 μg/m3, 95% CI for difference: 0.52 to 9.8, p=0.03) but not in particulate matter PM10 (before: 0.11 mg/m3, after: 0.06 mg/m3, difference 0.06 mg/m3, 95% CI for difference of means: −0.07 to 0.19, p=0.30).

Conclusions

The partial smoking ban was followed by a decrease in nicotine concentrations in ambient air. These improvements can be attributed to the introduction of the smoking ban since no other policy change occurred during this period. Although this shows that concentrations of SHS decreased significantly, protection was still incomplete and further action is necessary to improve indoor air quality.
CATALOG-BASED REPRESENTATION OF 2D TRIANGULATIONS
Authors: ALEARDI LUCA CASTELLI , DEVILLERS OLIVIER , MEBARKI ABDELKRIM
Published: August 2011

Several Representations and Coding schemes have been proposed to represent efficiently 2D triangulations. In this paper, we propose a new practical approach to reduce the main memory space needed to represent an arbitrary triangulation, while maintaining constant time for some basic queries. This work focuses on the connectivity information of the triangulation, rather than the geometric information (vertex coordinates), since the combinatorial data represents the main part of the storage. The main idea is to gather triangles into patches, to reduce the number of pointers by eliminating the internal pointers in the patches and reducing the multiple references to vertices. To accomplish this, we define and use stable catalogs of patches that are closed under basic standard update operations such as insertion and deletion of vertices, and edge flips. We present some bounds and results concerning special catalogs, and some experimental results that exhibit the practical gain of such methods.
INFLATING BALLS IS NP-HARD
Authors: BATOG GUILLAUME , GOAOC XAVIER
Published: August 2011

A collection [Formula: see text] of balls in ℝd is δ-inflatable if it is isometric to the intersection [Formula: see text] of some d-dimensional affine subspace E with a collection [Formula: see text] of (d + δ)-dimensional balls that are disjoint and have equal radius. We give a quadratic-time algorithm to recognize 1-inflatable collections of balls in any fixed dimension, and show that recognizing δ-inflatable collections of d-dimensional balls is NP-hard for δ ≥ 2 and d ≥ 3 if the balls' centers and radii are given by numbers of the form [Formula: see text] where a, …, e are integers.
SHORTEST DESCENDING PATHS: TOWARDS AN EXACT ALGORITHM
Authors: AHMED MUSTAQ , LUBIW ANNA
Published: August 2011

A path from s to t on a polyhedral terrain is descending if the height of a point p never increases while we move p along the path from s to t. Although a shortest path on a terrain unfolds to a straight line, a shortest descending path (SDP) does not. We give a full characterization of the bend angles of an SDP, showing that they follow a generalized form of Snell's law of refraction of light. The complexity of finding SDPs is open—only approximation algorithms are known. We reduce the SDP problem to the problem of finding an SDP through a given sequence of faces. We give polynomial time algorithms for SDPs on two special classes of terrains, but argue that the general case will be difficult.
EXTENDING THE DOUBLY LINKED FACE LIST FOR THE REPRESENTATION OF 2-PSEUDOMANIFOLDS AND 2-MANIFOLDS WITH BOUNDARIES
Authors: DOS SANTOS THIAGO R. , MEINZER HANS-PETER , MAIER-HEIN LENA
Published: August 2011

The Doubly Linked Face List (DLFL) is a data structure for mesh representation that always ensures topological 2-manifold consistency. Furthermore, it uses a minimal amount of computer memory and allows queries to be performed very efficiently. However, the use of the DLFL for the implementation of practical applications is very limited, mainly because of two drawbacks: (1) the DLFL is only able to represent 2-manifold objects; (2) its operators may be ambiguous, modifying the structure in an unexpected way from the user's point of view. In order to overcome these drawbacks, we present the Extended Doubly Linked Face List (XDLFL), which extends the DLFL for the representation of 2-pseudomanifolds and 2-manifolds with boundaries, increasing its applicability for practical software applications. Using these extensions, we also show how to avoid ambiguities in the original DLFL's operators. A new set of intuitive operators for the manipulation of the extensions and for the unambiguous manipulation of the data structure is also presented. The implementation of these extensions is straightforward, since the modifications to the DLFL are trivial and based on behavioral observations of the DLFL's operators. After integrating the extensions to the DLFL, memory usage increases very slightly, while is still smaller than the memory usage of other well-known data structures. Furthermore, queries related to the new extensions, such as whether an edge belongs to a boundary, may be performed very efficiently. The proposed extensions and their operators are very beneficial for applications such as surgery simulation softwares, where the interactions with the models, such as cutting or appending objects to each other, must be performed in an efficient and transparent manner.
EFFECTIVE FREE ENERGY FOR INDIVIDUAL DYNAMICS
Authors: GRAUWIN SEBASTIAN , HUNT DOMINIC , BERTIN ERIC , JENSEN PABLO
Published: August 2011

Physics and economics are two disciplines that share the common challenge of linking microscopic and macroscopic behaviors. However, while physics is based on collective dynamics, economics is based on individual choices. This conceptual difference is one of the main obstacles one has to overcome in order to characterize analytically economic models. In this paper, we build both on statistical mechanics and the game theory notion of Potential Function to introduce a rigorous generalization of the physicist's free energy, which includes individual dynamics. Our approach paves the way to analytical treatments of a wide range of socio-economic models and might bring new insights into them. As first examples, we derive solutions for a congestion model and a residential segregation model.
MULTI-SCALE ANALYSIS OF THE WEB OF DATA: A CHALLENGE TO THE COMPLEX SYSTEM'S COMMUNITY
Authors: GUÉRET CHRISTOPHE , WANG SHENGHUI , GROTH PAUL , SCHLOBACH STEFAN
Published: August 2011

The Web of Data (WoD) is an Internet-based network of data resources and their relations. It has recently taken flight and combines over a hundred interlinked data sources with more than 15 billion edges. A consequence of this recent success is that a paradigm shift has taken place: up to now the Web of Data could be studied, searched and maintained like a classical database; nowadays it has turned into a Complex System and needs to be studied as such. In this paper, we introduce the Web of Data as a challenging object of study and provide initial results on two network scales: the pure data-layer, and the global connection between groups data items. In this analysis, we show that the "official" abstract representation of the WoD does not fit the real distribution we derive from the lower scale. As interesting as these results are, bigger challenges for analysis await in the form of the highly dynamic character of the WoD, and the typed, and implicit, character of the edges which is, to the best of our knowledge, hitherto unstudied.
OPINIONS MANIPULATION: MEDIA, POWER AND GOSSIP
Authors: QUATTROCIOCCHI WALTER , CONTE ROSARIA , LODI ELENA
Published: August 2011

Despite the increasing diffusion of the Internet technology, TV remains the principal medium of communication. People's perceptions, knowledge, beliefs and opinions about matters of fact get (in)formed through the information reported on by the media.

However, a single source of information (and consensus) could be a potential cause of anomalies in the structure and evolution of a society.

Hence, as the information available (and the way it is reported) is fundamental for our perceptions and opinions, the definition of conditions allowing for a good information to be disseminated is a pressing challenge. In this paper starting from a report on the last Italian political campaign in 2008, we derive a socio-cognitive computational model of opinion dynamics where agents get informed by different sources of information. Then, a what-if analysis, performed through simulations on the model's parameters space, is shown. In particular, the scenario implemented includes three main streams of information acquisition, differing in both the contents and the perceived reliability of the messages spread. Agents' internal opinion is updated either by accessing one of the information sources, namely media and experts, or by exchanging information with one another. They are also endowed with cognitive mechanisms to accept, reject or partially consider the acquired information.
A COMPRESSED SENSING BASED APPROACH FOR SUBTYPING OF LEUKEMIA FROM GENE EXPRESSION DATA
Authors: TANG WENLONG , CAO HONGBAO , DUAN JUNBO , WANG YU-PING
Published: August 2011

With the development of genomic techniques, the demand for new methods that can handle high-throughput genome-wide data effectively is becoming stronger than ever before. Compressed sensing (CS) is an emerging approach in statistics and signal processing. With the CS theory, a signal can be uniquely reconstructed or approximated from its sparse representations, which can therefore better distinguish different types of signals. However, the application of CS approach to genome-wide data analysis has been rarely investigated. We propose a novel CS-based approach for genomic data classification and test its performance in the subtyping of leukemia through gene expression analysis. The detection of subtypes of cancers such as leukemia according to different genetic markups is significant, which holds promise for the individualization of therapies and improvement of treatments. In our work, four statistical features were employed to select significant genes for the classification. With our selected genes out of 7,129 ones, the proposed CS method achieved a classification accuracy of 97.4% when evaluated with the cross validation and 94.3% when evaluated with another independent data set. The robustness of the method to noise was also tested, giving good performance. Therefore, this work demonstrates that the CS method can effectively detect subtypes of leukemia, implying improved accuracy of diagnosis of leukemia.
ELECTRICAL TRANSPORT STUDIES IN 3Na2O–6.5B2O3 GLASSES
Authors: VAISH RAHUL , VARMA KALIDHINDI B. R.
Published: August 2011

Transparent 3Na2O–6.5B2O3 (NBO) glasses were fabricated via the conventional melt-quenching technique. X-ray powder diffraction (XRD) combined with Differential Scanning Calorimetric (DSC) studies carried out on the as-quenched samples confirmed their amorphous and glassy nature, respectively. The frequency and temperature dependent of the dielectric constant, electric modulus and electrical conductivity of the transparent NBO glasses were investigated in the 100 Hz–10 MHz frequency range. The electrical modulus and conductivity data have been rationalized using Jonscher's universal law. The bulk dc conductivity at various temperatures was extracted from the electrical relaxation data. The activation energy associated with dc conductivity is 0.52 ± 0.01eV, which is ascribed to the motion of Na+ ions in the glass matrix.
HIGH-FREQUENCY DIELECTRIC SPECTROSCOPY OF BaTiO3 CORE — SILICA SHELL NANOCOMPOSITES: PROBLEM OF INTERDIFFUSION
Authors: NUZHNYY D. , PETZELT J. , BOVTUN V. , KEMPA M. , SAVINOV M. , ELISSALDE C. , CHUNG U.-C. , MICHAU D. , ESTOURNÈS C. , MAGLIONE M.
Published: August 2011

Three types of BaTiO3 core — amorphous nanoshell composite ceramics were processed from the same core-shell powder by standard sintering, spark-plasma sintering and two-step sintering techniques and characterized by XRD, HRSEM and broadband dielectric spectroscopy in the frequency range 103 – 1013 Hz including the THz and IR range. The samples differed by porosity and by the amount of interdiffusion from the cores to shells, in correlation with their increasing porosity. The dielectric spectra were also calculated using suitable models based on effective medium approximation. The measurements revealed a strong dielectric dispersion below the THz range, which cannot be explained by the modeling, and whose strength was in correlation with the degree of interdiffusion. It is assigned to an effect of the interdiffusion layers, giving rise to a strong interfacial polarization. It appears that the high-frequency dielectric spectroscopy is an extremely sensitive tool for detection of any gradient layers and sample inhomogeneities even in dielectric materials with negligible conductivity.
PREPARATION AND CHARACTERIZATION OF LaFeO3 THIN FILMS ON (100) SrTiO3 SUBSTRATES BY PULSED LASER DEPOSITION
Authors: LIU HONG , ZHU JIANGUO , XIAO DINGQUAN
Published: August 2011

A single-crystalline, crack-free, epitaxial (100)c LaFeO3 films were in situ grown by pulsed laser deposition on (100) SrTiO3 substrates. X-ray diffraction, atomic force microscopy and transmission electron microscopy reveal that the LaFeO3 films have high crystalline quality, a very smooth surface, and an atomically sharp LaFeO3/SrTiO3 interface. The magnetic properties of the LaFeO3 films were obtained by a superconducting quantum interference device magnetometry. The saturated magnetization and coercive field of LaFeO3 films are 14 emu/cm3 and 600 Oe, respectively.
DIELECTRIC AND PIEZOELECTRIC PROPERTIES OF (K,Na)NbO3-BASED PIEZOELECTRIC CERAMICS
Authors: PATTERSON ERIC A. , CANN DAVID P.
Published: August 2011

Solid solutions based on Li , Ta and Sb -doped (K0.5Na0.5)NbO3 (KNN) lead-free perovskite systems were created using standard solid-state methods. X-ray diffraction was used to confirm that all compositions were single phase and to verify the phase transition from tetragonal to cubic at TC = 302° C . The three compositions examined, originally developed by Saito and Li , were shown to be strongly ferroelectric with sharp peaks in permittivity present at the Curie temperature. The optimum composition had loss tangent values below 5% up to 100 kHz at room temperature. Bipolar hysteresis measurements showed high values for both maximum polarization (25 and 21 μC/cm2) and remenant polarizations (20 and 16 μC/cm2) for undoped and 0.2 wt% CuO -doped samples. Maximum strain values of greater than 0.23% were observed.
A REVIEW ON LEAD-FREE PIEZOELECTRIC CERAMICS STUDIES IN CHINA
Authors: LU YI-QING , LI YONG-XIANG
Published: August 2011

There are a large number of research publications on the hot topic of environmental friendly lead-free piezoelectric materials worldwide in the last decade. The number of researchers and institutions involved from China is much larger than other countries or regions. The publications by Chinese researchers cover a broad spectrum on the preparations, structures, properties and applications of lead-free piezoelectric ceramics. This has motivated us to come out with a review on recent advances in development of lead-free piezoelectric ceramics in China. The emphases are especially on the preparation and electric properties of barium titanate-based materials, bismuth sodium titanate and related materials, alkaline niobate and related materials, bismuth layer-structured materials, as well as texture engineering of ceramics and some of their single crystals. Hopefully, this could give further impetus to the researchers to continue their efforts in this promising area and also draw the attentions from legislature, research office, industrial and publics.
ENHANCED MULTIFERROIC PROPERTIES OF La-DOPED BiFeO3 NANOTUBES FABRICATED THROUGH ANODIC ALUMINA TEMPLATE METHOD
Authors: HU ZHENG-LONG , WANG YAN , DAI JI-YAN , ZHOU DI , HU YONG-MING , GU HAO-SHUANG , BABA-KISHI KARIM Z.
Published: August 2011

Bi0.85La0.15FeO3 (BLFO) nanotubes with an average diameter of about 200 nm and wall thickness of about 20 nm are fabricated by sol–gel alumina template technique, and their room-temperature multiferroic properties are studied. Piezoelectricity and ferroelectricity in the BLFO nanotubes are revealed by piezoresponse force microscopy study of individual nanotube. Doping the BiFeO3 nanotubes with La reduces the crystallization temperature and results in a reduced lose of Bi and therefore improved multiferroic properties of the nanotubes. Enhanced weak ferromagnetism is also observed, and it is attributed to the nano-crystalline structure of the nanotubes.
DC BIAS ELECTRIC FIELD DEPENDENT PIEZOELECTRICITY FOR [001] POLEDPb(In1/2Nb1/2)O3–Pb(Mg1/3Nb2/3)O3–PbTiO3CRYSTALS
Authors: LI FEI , ZHANG SHUJUN , XU ZHUO , LI ZHENRONG , WEI XIAOYONG
Published: August 2011

The longitudinal piezoelectric response of [001] poled rhombohedral and orthorhombic Pb(In1/2Nb1/2)O3–Pb(Mg1/3Nb2/3)O3–PbTiO3crystals were investigated with respect to DC bias electric field, being in the range of -2~15 kV/cm. For rhombohedral crystals with compositions far away from morphotropic phase boundary (MPB), the piezoelectric response generally decreased with increasing positive DC bias field, while for crystals with MPB compositions, the piezoelectric response firstly decreased and then increased as function of DC bias. The piezoelectric response was found to decrease drastically when DC bias larger than phase transition field. On the other hand, the piezoelectric response was slightly enhanced for all the crystals as function of negative DC bias prior to the depolarization. To explain the obtained results, the field dependent piezoelectric coefficients in domain engineered crystals were analyzed based on thermodynamic approach.