bluuebunny/crossref_metadata_2025 huggingface dataset:
Life cycle of Chetoneura shennonggongensis (Diptera: Keroplatidae: Keroplatinae) from Jiangxi Province, China
Authors: Li Xue‐Zhen , Niu Chang‐Ying , Huang Qiu‐Ying , Lei Chao‐Liang , Stanley David W.
Published: May 2009

Abstract  We report the first description of the biology of non‐bioluminescent Keroplatidae from China. The life cycle of Chetoneura shennonggongensis is documented from laboratory culture and from field observations. The larval stage usually lasts 8–10 months. Large amounts of pupae are observed in late June, where they remain suspended horizontally or vertically from silk threads. The pupal suspending postures differ from other Keroplatidae species. Sexual differentiation is evident from the pupal stage. July is the peak time of adult emergence. Mating usually takes place immediately upon female emergence if adult males are available. The adult life span is short. Females live a maximum of 5 days and males 7 days. Egg development time varies from 20–30 days depending on environmental temperature. Larvae hang long sticky silk threads with a series of mucous droplets to capture prey. Some behaviors associated with snare construction and prey capture are also described.
Ace2, rather than ace1, is the major acetylcholinesterase in the silkworm, Bombyx mori
Authors: Chen Hui‐Juan , Liao Zhen , Hui Xiao‐Ming , Li Guo‐Qing , Li Fei , Han Zhao‐Jun
Published: May 2009

Abstract  Two acetylcholinesterase (ace) genes have been reported in many insect species. In pests such as Helicoverpa assulta and Plutella xylostellas, ace1 gene encodes the predominant synaptic enzyme that is the main target of organophosphorus (OP) and carbamate pesticides. It has been reported that pesticide selection has an impact on the ace gene evolution. The domesticated silkworm, Bombyx mori, also has two ace genes. We studied ace gene expression and enzyme activities in silkworm as this has not faced pesticide selection over the past decades. The expression levels of two ace genes, Bm‐ace1 and Bm‐ace2, were estimated by quantitative real‐time polymerase chain reaction. Bm‐ace2 was expressed more highly than Bm‐ace1 in all tested samples of different developmental stages or tissues, suggesting ace2, rather than ace1, is the major type of acetylcholinesterase (AChE) in Bombyx mori. This is inconsistent with the aforementioned lepidopterons agricultural pests, partly be due to the widespread use of pesticides that may induce high expression of the ace1 gene in these pests. Besides high expression in the head, Bm‐ace1 also expresses highly in the silk glands and Bm‐ace2 is abundant in the germline, implying both ace genes may have potential non‐hydrolytic roles in development. Furthermore, we found that the mRNA levels of two ace genes and their ratios (ace2/ace1) change day to day in the first and third instars. This challenges the conventional method of estimating enzymatic activity using crude extract as an enzyme solution, as it is a mixture of AChE1 and AChE2. An efficient and simple method for separating different AChEs is necessary for reliable toxicological analyses.
OXIDATIVE AND FLAVOR STABILITY OF TORTILLA CHIPS FRIED IN EXPELLER PRESSED LOW LINOLENIC ACID SOYBEAN OIL*
Authors: WARNER KATHLEEN
Published: May 2009

To determine effects of expeller oil pressing and decreased linolenic acid, intermittent batch frying tests were conducted with tortilla chips using soybean oil (SBO), expeller pressed SBO (EPSBO), expeller pressed low linolenic SBO (EPLLSBO), high oleic sunflower oil, corn oil and hydrogenated SBO for up to 35 h of frying. Chips were aged at 25C and trained, experienced analytical sensory panelists evaluated their flavor. Oxidative stability of the chips was determined by hexanal analyses and oil fry life was measured by total polar compounds. The stability of tortilla chips fried in EPLLSBO was significantly better than chips fried in SBO or EPSBO as judged by rancid flavor intensity and hexanal formation after storage. This effect may be due, in part, to less linolenic acid in EPLLSBO and better tocopherol retention compared to EPSBO. The combination of expeller pressing and low linolenic acid (EPLLSBO) produced a significantly more stable fried product than expeller pressing (EPSBO) alone.

PRACTICAL APPLICATIONS

Food manufacturers are interested in oils that can be used for frying as alternatives to trans fat‐containing hydrogenated fats. Since polyunsaturated vegetable oils are not sufficiently oxidatively stable for frying, alternatives such as modified fatty acid composition oils, additives and oil processing techniques could be used individually or in combination to increase fry life of the oil and shelf life of foods. Although expeller pressing of SBO or reducing linolenic acid of SBO alone have not given SBO the stability equivalent to HSBO, we found that combining decreased linolenic acid and expeller pressing of SBO produced frying oil and fried tortilla chips with the stability similar to that of hydrogenated fat in early stages of frying.
FATTY ACID COMPOSITION IN TISSUES OF MICE FED DIETS CONTAINING CONJUGATED LINOLENIC ACID AND CONJUGATED LINOLEIC ACID
Authors: YUAN GAO‐FENG , SINCLAIR ANDREW J. , SUN HAI‐YAN , LI DUO
Published: May 2009

The influence of 1% alpha‐eleostearic acid (α‐ESA, cis9,trans11,trans 13‐18:3) and 1% punicic acid (PA, cis9,trans11,cis13‐18:3) on fatty acid composition in mouse tissues was compared with conjugated linoleic acid (CLA, mixture of primarily cis9,trans11‐ and trans10,cis12‐18:2) in the present study. The content (% total fatty acids) of 18:2n‐6 was significantly reduced in the heart and adipose tissues, and total polyunsaturated fatty acids (PUFAs) and n‐6 PUFA were significantly reduced in adipose tissue by α‐ESA, PA and CLA feeding. The content of 22:6n‐3 and total n‐3 PUFA were significantly increased in the liver, kidney and heart by PA feeding, but not by α‐ESA. In contrast to PA, supplementation with CLA significantly decreased 22:6n‐3 in the liver, kidney and heart. The content of 20:4n‐6 was significantly decreased in the liver and kidney by CLA feeding, but not by α‐ESA and PA. The present results indicate that α‐ESA, PA and CLA have differential effects on 22:6n‐3 and 20:4n‐6 content in mouse tissues.

PRACTICAL APPLICATIONS

Conjugated linolenic acid (CLnA), a group of octadecatrienoic acid isomers with a conjugated triene system, has been reported to exhibit favorable physiological effects, including anticancer properties and regulation of lipid metabolism. Punicic acid and alpha‐eleostearic acid, two isomers of CLnA, have been shown to convert into cis9,trans11‐18:2 in vivo. The effect of CLnA on fatty acid composition in mouse tissues was investigated in comparison with CLA mixtures in the present study. The data obtained here could provide information for the potential application of CLnA‐containing seeds as functional food ingredients, a natural source of endogenously formed cis9,trans11‐18:2 and a dietary feeding strategy to beneficially modify the fatty acid composition of animal tissues.
CHARACTERISTICS OF DRUPES, PHENOLIC CONTENT AND ANTIOXIDANT CAPACITY OF ITALIAN OLIVE FRUITS
Authors: BAIANO ANTONIETTA , GAMBACORTA GIUSEPPE , TERRACONE CARMELA , PREVITALI MARIA ASSUNTA , LA NOTTE ENNIO
Published: May 2009

Drupe characteristics, phenolic content and antioxidant capacity of olive fruits were studied for 12 Italian oil cultivars grown in two areas (Cerignola and Torremaggiore) of Daunia district. The effects of plantation place were higher than those exerted by cultivars on drupe characteristics such as weight, pulp/stone ratio, oil content and maturation index. Olive fruits from Cerignola, which is located at a lower altitude than Torremaggiore, showed the highest phenolic content. The highest phenolic content (14 g gallic acid/kg dry olive) was detected on Peranzana and Cellina di Nardò grown in Cerignola groves. The lowest values were registered for FS17 and Cima di Melfi (about 7 g/kg). 1‐Acetoxypinoresinol, 3,4‐dihydroxyphenylethyl 4‐formyl‐3‐formylmethyl‐4‐hexenoate, the dialdehydic form of decarboxymethyl elenolic acid linked to hydroxytyrosol (3,4‐DHPEA‐EDA), hydroxytyrosol and luteolin, were the phenolic compounds detected in a greater amount and in most of the cultivars. Independently on the assay applied, the highest antioxidant activity was detected for Cellina di Nardò (Cerignola). The lowest antioxidant activity values were different depending on the method applied. According to the 2,2′‐azino‐bis‐(3‐ethylbenzothiazoline)‐6‐sulfonic acid (ABTS) assay, the lowest value was detected for Moraiolo from Torremaggiore, whereas Nociara showed the lowest contribution to the inhibition of lipid oxidation (β‐carotene beaching assay). A strong positive linear correlation (R = 0.82) existed between total phenolic content and antioxidant activity measured according to the ABTS method, whereas a low linear correlation coefficient (R = 0.36) was obtained when the β‐carotene bleaching assay was used.

PRACTICAL APPLICATIONS

The experimental results obtained with this research could help farmers to increase their knowledge of the minor components of some major and minor Italian olive cultivars. In fact, there are very few works on the characterization of olive fruits destined for oil production. The analytical findings of this study can also provide useful information to the oil industries interested in processing olives having high phenolic content and high antioxidant capacity. Furthermore, the diffusion of these results could help consumers to choose, among monovarietal extra virgin oils available in the market, those derived from the cultivars rich in antioxidant compounds.
DELIVERY OF LYCOPENE TO PHYSIOLOGICALLY RELEVANT VASCULAR CELLS
Authors: LORENZ MARIO , STANGL VERENA , JACOB CHRISTINE , DAEMEN KERSTIN , BÖHM VOLKER , FRÖHLICH KATI , BAUMANN GERT , STANGL KARL , SIMONE ROSSELLA , PALOZZA PAOLA
Published: May 2009

Lycopene most likely contributes to the positive health effects of tomatoes on the cardiovascular system. However, elucidation of underlying cellular mechanisms is hampered by the intricate solubility of lycopene in aqueous solutions. Cells relevant to the cardiovascular system, including bovine aortic endothelial cells (BAECs), the monocytic cell line THP‐1, and RAT‐1 fibroblasts, were treated for various time periods (0–72 h) with different concentrations of lycopene (1, 5, and 10 µM), solubilized either in tetrahydrofuran (THF) or micelles as solvents. Incubation of all three cell types led to a concentration‐ and time‐dependent increase in cellular lycopene content. Both vehicles tested, THF and micelles, proved equally effective in the delivery of lycopene to cells. A marked difference in the amount of lycopene incorporated was observed among the various cell types. Compared with THP‐1 cells, the uptake of lycopene using both solvents was higher in BAECs and RAT‐1 fibroblasts for all concentrations and time points tested.

PRACTICAL APPLICATIONS

Epidemiological data indicate a beneficial effect for consumption of tomato products in the prevention of cardiovascular diseases. Only limited data are available on the cellular uptake of lycopene in vascular cells. Lycopene was successfully delivered to different cells relevant for the cardiovascular system. These results represent an important prerequisite for the study of molecular and cellular mechanisms by which lycopene may exert its beneficial effects on the cardiovascular system.
Left Ventricular Geometric Patterns in Normotensive Type 2 Diabetic Patients in Nigeria: An Echocardiographic Study
Authors: Ojji Dike B. , Adebiyi Adewole A. , Oladapo Olulola O. , Adeleye Jokotade A. , Aje Akinyemi , Ogah Okechukwu S. , Adebayo Adedeji K. , Falase Ayodele O.
Published: May 2009

Left ventricular hypertrophy has been linked with diabetes mellitus and abnormal glucose tolerance in several studies. Most previous studies have been carried out in the western world with dearth of data in native Africans. A total of 122 type 2 diabetic patients with a mean age of 55.0±8.5 years and another 90 normal patients with a mean age of 55.4±8.7 years were recruited for the study. Two‐dimensional guided M‐mode echocardiography was performed on each patient. In the diabetic patients, 49.2% had normal geometry, 23.0% had concentric hypertrophy, 13.0% had concentric remodeling, and 14.8% had eccentric hypertrophy. In the control group, 72.2% had normal geometry, 4.4% had concentric hypertrophy, 11.2% had concentric remodeling, and 12.2% had eccentric hypertrophy. In a multiple regression analysis, there was significant difference in the geometric pattern of the diabetics and controls (χ2=11.09, P<.001). Diabetes mellitus is independently associated with left ventricular structural changes in Nigerian diabetics.
Isolation and characterization of 10 polymorphic microsatellite markers from striped marlin, Tetrapturus audax
Authors: PURCELL C. M. , HARRISON J. S. , EDMANDS S.
Published: May 2009

We present the isolation and characterization of 10 microsatellite loci for striped marlin, Tetrapturus audax. Thirty individuals from each of four locations revealed that all loci were polymorphic with two to 31 alleles per locus. Observed levels of heterozygosity ranged from 0.3000 to 0.9667. Significant deviations from Hardy–Weinberg equilibrium were detected in two loci, TA105 in Hawaii and New Zealand and TA155 in Hawaii, and null alleles may be present in loci TA105 and TA155 in those locations, and in locus TA193 in Mexico. No significant linkage disequilibrium was detected in any pairwise‐locus comparison.
Microsatellite markers for the praying mantid Ciulfina rentzi (Liturgusidae)
Authors: ATTARD CATHERINE R. M. , HOLWELL GREG I. , SCHWARTZ TONIA S. , UMBERS KATE D. L. , STOW ADAM , HERBERSTEIN MARIE E. , BEHEREGARAY LUCIANO B.
Published: May 2009

Nine polymorphic microsatellite loci were characterized from an enrichment library of the Australian praying mantid Ciulfina rentzi, a group with a unique reproductive morphology and behaviour. The number of alleles per locus ranged from three to 16 and heterozygosity from 0.24 to 0.94. These markers are the first microsatellites developed for any praying mantid. They will be useful for paternity analysis and for population genetic studies in the Wet Tropics World Heritage Region of Australia.
Mechanical and neural stretch responses of the human soleus muscle at different walking speeds
Authors: Cronin Neil J. , Ishikawa Masaki , Grey Michael J. , Af Klint Richard , Komi Paavo V. , Avela Janne , Sinkjaer Thomas , Voigt Michael
Published: May 2009

During human walking, a sudden trip may elicit a Ia afferent fibre mediated short latency stretch reflex. The aim of this study was to investigate soleus (SOL) muscle mechanical behaviour in response to dorsiflexion perturbations, and to relate this behaviour to short latency stretch reflex responses. Twelve healthy subjects walked on a treadmill with the left leg attached to an actuator capable of rapidly dorsiflexing the ankle joint. Ultrasound was used to measure fascicle lengths in SOL during walking, and surface electromyography (EMG) was used to record muscle activation. Dorsiflexion perturbations of 6 deg were applied during mid‐stance at walking speeds of 3, 4 and 5 km h−1. At each walking speed, perturbations were delivered at three different velocities (slow: ∼170 deg s–1, mid: ∼230 deg s–1, fast: ∼280 deg s–1). At 5 km h−1, fascicle stretch amplitude was 34–40% smaller and fascicle stretch velocity 22–28% slower than at 3 km h−1 in response to a constant amplitude perturbation, whilst stretch reflex amplitudes were unchanged. Changes in fascicle stretch parameters can be attributed to an increase in muscle stiffness at faster walking speeds. As stretch velocity is a potent stimulus to muscle spindles, a decrease in the velocity of fascicle stretch at faster walking speeds would be expected to decrease spindle afferent feedback and thus stretch reflex amplitudes, which did not occur. It is therefore postulated that other mechanisms, such as altered fusimotor drive, reduced pre‐synaptic inhibition and/or increased descending excitatory input, acted to maintain motoneurone output as walking speed increased, preventing a decrease in short latency reflex amplitudes.
Intercostal muscle blood flow limitation in athletes during maximal exercise
Authors: Vogiatzis Ioannis , Athanasopoulos Dimitris , Habazettl Helmut , Kuebler Wolfgang M. , Wagner Harrieth , Roussos Charis , Wagner Peter D. , Zakynthinos Spyros
Published: May 2009

We investigated whether, during maximal exercise, intercostal muscle blood flow is as high as during resting hyperpnoea at the same work of breathing. We hypothesized that during exercise, intercostal muscle blood flow would be limited by competition from the locomotor muscles. Intercostal (probe over the 7th intercostal space) and vastus lateralis muscle perfusion were measured simultaneously in ten trained cyclists by near‐infrared spectroscopy using indocyanine green dye. Measurements were made at several exercise intensities up to maximal (WRmax) and subsequently during resting isocapnic hyperpnoea at minute ventilation levels up to those at WRmax. During resting hyperpnoea, intercostal muscle blood flow increased linearly with the work of breathing (R2= 0.94) to 73.0 ± 8.8 ml min−1 (100 g)−1 at the ventilation seen at WRmax (work of breathing ∼550–600 J min−1), but during exercise it peaked at 80% WRmax (53.4 ± 10.3 ml min−1 (100 g)−1), significantly falling to 24.7 ± 5.3 ml min−1 (100 g)−1 at WRmax. At maximal ventilation intercostal muscle vascular conductance was significantly lower during exercise (0.22 ± 0.05 ml min−1 (100 g)−1 mmHg−1) compared to isocapnic hyperpnoea (0.77 ± 0.13 ml min−1 (100 g)−1 mmHg−1). During exercise, both cardiac output and vastus lateralis muscle blood flow also plateaued at about 80% WRmax (the latter at 95.4 ± 11.8 ml min−1 (100 g)−1). In conclusion, during exercise above 80% WRmax in trained subjects, intercostal muscle blood flow and vascular conductance are less than during resting hyperpnoea at the same minute ventilation. This suggests that the circulatory system is unable to meet the demands of both locomotor and intercostal muscles during heavy exercise, requiring greater O2 extraction and likely contributing to respiratory muscle fatigue.
GES-11, a Novel Integron-Associated GES Variant in
Acinetobacter baumannii
Authors: Moubareck Carole , Brémont Sylvie , Conroy Marie-Christine , Courvalin Patrice , Lambert Thierry
Published: May 2009

New extended-spectrum β-lactamase GES-11 was detected in
Acinetobacter baumannii
BM4674. The enzyme conferred resistance to β-lactams, including aztreonam, and reduced susceptibility to carbapenems. The structural gene was part of a class 1 integron borne by self-transferable plasmid pIP847. GES-type β-lactamases have not been reported previously in
A. baumannii
.
In Vitro Activity of Garenoxacin against
Streptococcus pneumoniae
Mutants with Characterized Resistance Mechanisms
Authors: Yamamoto Kazuko , Yanagihara Katsunori , Sugahara Kazuyuki , Imamura Yoshifumi , Seki Masafumi , Izumikawa Koichi , Kakeya Hiroshi , Yamamoto Yoshihiro , Hirakata Yoichi , Kamihira Shimeru , Kohno Shigeru
Published: May 2009

We evaluated the potency of garenoxacin in selecting resistant
Streptococcus pneumoniae
mutants by determining its mutant prevention concentration, using strains with and without topoisomerase gene mutations, and compared its potency to that of other quinolones. Garenoxacin had a significantly greater potency against pneumococci, including strains containing topoisomerase mutations. Genetic analysis of the
S. pneumoniae
mutants created by garenoxacin revealed that the
gyrA
gene was a primary target of garenoxacin.
In Vitro Activities of Telavancin and Vancomycin against Biofilm-Producing
Staphylococcus aureus
,
S
.
epidermidis
, and
Enterococcus faecalis
Strains
Authors: LaPlante Kerry L. , Mermel Leonard A.
Published: May 2009

We investigated the activities of telavancin and vancomycin against biofilm-producing
Staphylococcus
and
Enterococcus
strains. At clinically attainable concentrations, telavancin was active against bacteria embedded in biofilm (minimal biofilm eradication concentration [MBEC], 0.125 to 2 μg/ml) and inhibited biofilm formation at concentrations below the MIC. Vancomycin did not demonstrate the same activity (MBEC, ≥512 μg/ml) against
Staphylococcus aureus
and
Enterococcus faecalis
. Telavancin may have a unique role in biofilm-associated infections.
Regulation of Expression of the
Haemophilus ducreyi
LspB and LspA2 Proteins by CpxR
Authors: Labandeira-Rey Maria , Mock Jason R. , Hansen Eric J.
Published: May 2009

The LspA1, LspA2, and LspB proteins of
Haemophilus ducreyi
comprise a two-partner secretion system that has been shown to be necessary for
H. ducreyi
to inhibit phagocytosis by immune cells in vitro. Inactivation of
lspA1
resulted in increased levels of LspA2, suggesting that these two proteins are differentially controlled (C. J. Ward et al., Infect. Immun. 71:2478-2486, 2003). Expression of LspA2 but not LspA1 was shown to be both growth phase dependent and affected by the presence of fetal calf serum (FCS) in the growth medium. In addition, neither LspA1 nor LspA2 could be detected in culture supernatant fluid in the absence of FCS. DNA microarray analysis revealed that 324
H. ducreyi
genes were differentially regulated after growth in the presence of FCS. Among these, the CpxRA two-component sensory transduction system was downregulated by the presence of FCS. Inactivation of
cpxR
resulted in increased expression of both LspB and LspA2. Electrophoretic mobility shift assays showed that a recombinant
H. ducreyi
CpxR protein bound the promoter region of the
lspB-lspA2
operon. The
cpxR
and
cpxA
genes were shown to be part of an operon containing two additional genes in
H. ducreyi
35000HP. This is the first description of a two-component sensory transduction system regulating a proven virulence factor of
H. ducreyi.
Synthesis of Aib-containing cyclopeptides via the ‘azirine/oxazolone method’
Authors: Dannecker-Dörig Ingeborg , Linden Anthony , Heimgartner Heinz
Published: May 2009

The cyclic pentapeptide cyclo[Gly-Phe(2Me)-Aib-Aib-Gly], containing three α,α-disubstituted α-amino acids, was prepared by cyclization of H-Gly-Phe(2Me)-Aib-Aib-Gly-OH with diphenyl phosporazidate (DPPA) in 60% yield. The synthesis of the linear precursor was performed by using the ‘azirine/oxazolone method’, in which the α,α-disubstituted α-amino acids were introduced by coupling of the corresponding amino or peptide acid with a 2,2-disubstituted 3-amino-2H-azirine. Whereas the cyclization of an analogous hexapeptide afforded the cyclopeptide in 42% yield, the corresponding tetrapeptide yielded a 1:2 mixture of the monomeric and dimeric cyclopeptide. In the case of the tripeptide H-Gly-Phe(2Me)-Aib-OH, the cyclization with DPPA led to the dimeric cyclohexapeptide exclusively.
ON THE DEFINITION OF L2-BETTI NUMBERS OF EQUIVALENCE RELATIONS
Authors: NESHVEYEV SERGEY , RUSTAD SIMEN
Published: May 2009

We show that the L2-Betti numbers of equivalence relations defined by R. Sauer coincide with those defined by D. Gaboriau.
CLONES FROM IDEALS
Authors: BEIGLBÖCK MATHIAS , GOLDSTERN MARTIN , HEINDORF LUTZ , PINSKER MICHAEL
Published: May 2009

On an infinite base set X, every ideal of subsets of X can be associated with the clone of those operations on X which map small sets to small sets. We continue earlier investigations on the position of such clones in the clone lattice.
SOME FISSION PROBLEMS CIRCA 1950 AND 2008
Authors: ŚWIATECKI W. J.
Published: May 2009

In the first part of the talk I will recall conversations with Niels Bohr and John Wheeler concerning the puzzle of the asymmetric mass division in nuclear fission. In 1950 this was the outstanding problem in fission theory, and for a brief period I foolishly believed to have found the solution by relaxing the incompressibility assumption in the liquid drop model of fission. In the second part I will describe recent progress in the formulation and streamlining of the transition-state formulae for the competition between the disintegration of an excited compound nucleus by particle emission and fission.
ELISe: A NEW FACILITY FOR UNPRECEDENTED EXPERIMENTAL NUCLEAR FISSION STUDIES
Authors: TAIEB J. , BELIER G. , CHATILLON A. , GRANIER T. , KELIC A. , RICCIARDI V. , SCHMIDT K.-H. , VOSS B. , COSTE-DELCLAUX M. , DIOP C. , JOUANNE C. , SCHMITT C. , AICHE M. , CZAJKOWSKI S. , JURADO B. , AUDOUIN L. , PEYRE J. , ROSIER P. , TASSAN-GOT L. , BERTOUMIEUX E. , DORE D. , DUPONT E. , LETOURNEAU A. , PANEBIANCO S.
Published: May 2009

A novel experimental program aiming to study the properties of fragments and neutrons emitted in the fission process has been initiated. The experiment will be held at the ELISe electron-ion collider to be constructed at GSI, Darmstadt in the framework of the FAIR extension of the facility. The experiment will take advantage of the inverse kinematics allowing, in particular, a total mass and charge resolution for all fission fragments.
NUCLEAR FISSION WITHIN THE MEAN-FIELD APPROACH
Authors: SKALSKI J.
Published: May 2009

We discuss the mean-field instanton method for calculating decay rates of the sponteneous fission. Based on our recent work, we stress the role of the velocity-momentum relations which make the instanton action minimal, and the choice of a time-even density matrix and a time-odd hermitian operator as special variables making the adiabatic limit transparent. We also present an analytic study of a simple model of barrier tunneling, which illustrates the importance of the velocity-momentum constraints.
GLOBAL NUCLEAR STRUCTURE ASPECTS OF TENSOR INTERACTION
Authors: SATUŁA W. , ZALEWSKI M. , DOBACZEWSKI J. , OLBRATOWSKI P. , RAFALSKI M. , WERNER T. R. , WYSS R. A.
Published: May 2009

A direct fit of the isoscalar spin-orbit and both isoscalar and isovector tensor coupling constants to the f5/2 - f7/2 SO splittings in 40 Ca , 56 Ni , and 48 Ca requires (i) a significant reduction of the standard isoscalar spin-orbit strength and (ii) strong attractive tensor coupling constants. The aim of this paper is to address the consequences of these strong attractive tensor and weak spin-orbit fields on total binding energies, two-neutron separation energies and nuclear deformability.
DESCRIPTION OF EXPERIMENTAL FISSION BARRIERS OF HEAVY NUCLEI
Authors: SOBICZEWSKI A. , KOWAL M.
Published: May 2009

The accuracy of the description of the experimental heights of the fission barriers of heavy nuclei is studied. Four theoretical descriptions are considered. It is found that the average discrepancy between theoretical and experimental values for 18 even-even nuclei is about 0.8 MeV, while the largest discrepancy is about 2 MeV.
GLOBAL VIEW ON FISSION CHANNELS
Authors: BÖCKSTIEGEL C. , STEINHÄUSER S. , CLERC H.-G. , GREWE A. , HEINZ A. , DE JONG M. , MÜLLER J. , VOSS B. , JUNGHANS A. R. , KELIĆ A. , SCHMIDT K.-H.
Published: May 2009

A global view on the properties of fission channels is presented. Surprisingly, the positions of the two asymmetric fission channels are found to be constant in atomic number over the whole range of systems investigated.
THE SHAPES OF CONDITIONAL EQUILIBRIUM IN THE LIQUID-DROP MODEL
Authors: IVANYUK FEDIR
Published: May 2009

The shape of the nuclear surface is defined looking for the minimum of liquid drop energy under the constraint of fixed volume, elongation and mass asymmetry. The method does not rely on any shape parameterization and leads to the shapes with the lowest energy. The results obtained with several deformation constraints are compared. The numerical methods used here for solving the variational problem allow for the straightforward generalizations which could include the surface diffusenes, nuclear interaction, separated shapes, eventually shell effects.
ASYMMETRY AND SPIN-ORBIT EFFECTS IN BINDING ENERGY IN THE EFFECTIVE NUCLEAR SURFACE APPROXIMATION
Authors: MAGNER A. G. , SANZHUR A. I. , GZHEBINSKY A. M.
Published: May 2009

Isoscalar and isovector particle densities are derived analytically by using the approximation of a sharp edged nucleus within the local energy density approach with the proton-neutron asymmetry and spin-orbit effects. Equations for the effective nuclear-surface shapes as collective variables are derived up to the higher order corrections in the form of the macroscopic boundary conditions. The analytical expressions for the isoscalar and isovector tension coefficients of the nuclear surface binding energy and the finite-size corrections to the β stability line are obtained.
EFFECT OF NON-AXIAL DEFORMATIONS ON THE FISSION BARRIER OF HEAVY AND SUPERHEAVY NUCLEI
Authors: KOWAL M. , SOBICZEWSKI A.
Published: May 2009

The effect of the non-axial quadrupole deformation γ2 on the height of the static fission barrier B f of heaviest nuclei is studied. Even-even nuclei with the proton number 92 ≤ Z ≤ 122 and the neutron number 136 ≤ N ≤ 188 are considered. The analysis is done within a macroscopic-microscopic approach with the use of a large deformation space. It is found that the effect reduces B f by up to about 2 MeV.
QUANTUM MONTE CARLO METHOD APPLIED TO STRONGLY CORRELATED DILUTE FERMI GASES WITH FINITE EFFECTIVE RANGE
Authors: WLAZŁOWSKI GABRIEL , MAGIERSKI PIOTR
Published: May 2009

We discuss the Auxiliary Field Quantum Monte Carlo (AFQMC) method applied to dilute neutron matter at finite temperatures. We formulate the discrete Hubbard-Stratonovich transformation for the interaction with finite effective range which is free from the sign problem. The AFQMC results are compared with those obtained from exact diagonalization for a toy model. Preliminary calculations of energy and chemical potential as a function of temperature are presented.
JACOBI BIFURCATION IN HOT ROTATING NUCLEI WITH A LSD + YUKAWA FOLDED APPROACH
Authors: BARTEL JOHANN , NERLO-POMORSKA BOZENA , POMORSKI KRZYSZTOF
Published: May 2009

The "Modified Funny-Hills parametrisation" is used together with the Lublin-Strasbourg Drop Model and Strutinsky type shell corrections to determine the stability of hot rotating nuclei. Both the macroscopic and the microscopic part of the nuclear energy are evaluated by taking into account their dependence on the nuclear temperature and the rotational angular momentum. The Jacobi transition into triaxial shapes and the centrifugal-fission instability are studied.
SYMMETRY BREAKING PHENOMENA IN MESOSCOPIC SYSTEMS: QUANTUM DOTS AND ROTATING NUCLEI
Authors: NAZMITDINOV R. G. , PUENTE A.
Published: May 2009

A brief description of excited and ground states in two-dimensional quantum dots and rotating nuclei is presented within a mean field approach and a random-phase approximation (RPA). We discuss the procedure to restore the rotational symmetry broken at the mean field, which can be extended for other symmetry breaking cases. We propose to consider a disappearance of collective excitations in the rotating frame as a manifestation of symmetry breaking phenomena of the rotating mean field. In particular, we demonstrate that the disappearance of a collective octupole mode in the rotating frame in 162 Yb gives rise to the nonaxial octupole deformation.
FROM FISSION TO MULTIFRAGMENTATION AND BACK
Authors: GULMINELLI FRANCESCA , LEHAUT GREGORY
Published: May 2009

Multifragmentation, defined as the decay of a highly excited nuclear source into more than two fragments, is generally considered in the nuclear physics community as a completely different phenomenon than nuclear fission, and tentatively interpreted as the finite system counterpart of the nuclear matter liquid-gas phase transition. Recent theoretical developements on phase transitions with non-saturating long-range interactions allow to revisit the simple picture of fragmentation as a condensation phenomenon, and new connections with the phenomenology of hot fission can be advanced. The generic existence of a fission channel in the nuclear phase diagram will be sketched in the framework of a simple exactly solvable model, and connections to experimental data will be given.
FISSION QUADRUPOLE MASS PARAMETERS IN HF+BCS AND HFB METHODS
Authors: BARAN A. , SHEIKH J. A. , STASZCZAK A. , NAZAREWICZ W.
Published: May 2009

The self-consistent Hartree-Fock+BCS and Hartree-Fock-Bogoliubov methods are compared at large nuclear deformations. The calculations are carried out for the fission pathway and quadrupole mass parameter of 252 Fm .
STRUCTURE EFFECTS IN THE DECAY OF SUPERHEAVY NUCLEI
Authors: PARKHOMENKO A. , HOFMANN S. , SOBICZEWSKI A.
Published: May 2009

A detailed and complete theoretical analysis of an α-decay genetic chain of a superheavy nucleus is performed. A well established chain of the nucleus 269 Ds is chosen. The analysis is done in a macroscopic-microscopic approach.
POPULATION OF ROTATION BANDS IN γ-DECAY OF ANALOG STATES IN 23Na
Authors: USHAKOV I. V. , VODIN A. N. , KHOMYAKOV G. K.
Published: May 2009

The γ-decay from [Formula: see text] isobaric analog levels was studied in odd-mass nucleus 23 Na . The investigations were performed using the proton beam at E p = 1623, 1721, 1803 and 1835 keV. It was shown that during γ-decay, mainly low-lying levels of 23 Na are populated; among these levels, we could isolate rotational bands with [Formula: see text] and [Formula: see text], based on the seventh [Formula: see text] and ninth [Formula: see text] orbits of the Nilsson scheme, respectively. The intensities of the M1 transitions were compared with the results of the calculations within the Nilsson model.
SIMPLE TOOL TO SEARCH QUASI-MAGIC STRUCTURES IN DEFORMED NUCLEI
Authors: NERLO-POMORSKA BOŻENA , POMORSKI KRZYSZTOF
Published: May 2009

Evaluation of shell effects in nuclei plays an important role in studying the nuclear structure. In the Strutinsky method the smooth energy of the nucleus is obtained by a folding procedure of the single-particle (s.p.) energy density in the s.p. energy space e. An alternative way of energy smoothing is obtained by folding the s.p. energy sum in the particle-number space [Formula: see text]. For non degenerated s.p. spectra both types of folding yield smooth energies which are close to each other. In the case of strongly degenerated spectra which appear at sphericity or in regions of shape isomers, the smooth energy obtained by the [Formula: see text]-folding is a couple of MeV larger than the traditional average Strutinsky energy. It is shown that this smooth energy difference can serve as a simple tool to search for magic or quasi-magic structures in the s.p. spectra, e.g. to find shape isomers in the multidimensional deformation space.
VALUES AT s = -1 OF L-FUNCTIONS FOR MULTI-QUADRATIC EXTENSIONS OF NUMBER FIELDS, AND THE FITTING IDEAL OF THE TAME KERNEL
Authors: SANDS JONATHAN W.
Published: May 2009

Fix a Galois extension [Formula: see text] of totally real number fields such that the Galois group G has exponent 2. Let S be a finite set of primes of F containing the infinite primes and all those which ramify in [Formula: see text], let [Formula: see text] denote the primes of [Formula: see text] lying above those in S, and let [Formula: see text] denote the ring of [Formula: see text]-integers of [Formula: see text]. We then compare the Fitting ideal of [Formula: see text] as a ℤ[G]-module with a higher Stickelberger ideal. The two extend to the same ideal in the maximal order of ℚ[G], and hence in ℤ[1/2][G]. Results in ℤ[G] are obtained under the assumption of the Birch–Tate conjecture, especially for biquadratic extensions, where we compute the index of the higher Stickelberger ideal. We find a sufficient condition for the Fitting ideal to contain the higher Stickelberger ideal in the case where [Formula: see text] is a biquadratic extension of F containing the first layer of the cyclotomic ℤ2-extension of F, and describe a class of biquadratic extensions of F = ℚ that satisfy this condition.
ON SETS SUCH THAT THE PARTITION FUNCTION IS EVEN FROM A CERTAIN POINT ON
Authors: BACCAR N. , BEN SAÏD F.
Published: May 2009

Let P ∈ 𝔽2[z] with P(0) = 1 and degree (P) ≥ 1. It is not difficult to prove (cf. [4,14]) that there is a unique subset [Formula: see text] of ℕ such that [Formula: see text] (mod 2), where [Formula: see text] denotes the number of partitions of n with parts in [Formula: see text]. However, finding the elements of such sets for general P seems to be hard. In this paper, we obtain solutions to this problem for a large class of polynomials P. Moreover, we give asymptotics for the counting function [Formula: see text].
ON THE NUMBER OF REPRESENTATIONS OF INTEGERS BY THE SUMS OF QUADRATIC FORMS $x_1^2 + x_1x_2 + 3x_2^2$
Authors: SHAVGULIDZE KETEVAN
Published: May 2009

We shall obtain the formulae for the number of representations of positive integers by a direct sum of k binary quadratic forms of the kind [Formula: see text], when k = 3, 4, 5.
REDUCTION modp OF SUBGROUPS OF THE MORDELL–WEIL GROUP OF AN ELLIPTIC CURVE
Authors: AKBARY AMIR , MURTY V. KUMAR
Published: May 2009

Let E be an elliptic curve defined over ℚ. Let Γ be a free subgroup of rank r of E(ℚ). For any prime p of good reduction, let Γp be the reduction of Γ modulo p and Ep be the reduction of E modulo p. We prove that if E has CM then for all but o(x/ log x) of primes p ≤ x, [Formula: see text] where ∊(p) is any function of p such that ∊(p) → 0 as p → ∞. This is a consequence of two other results. Denote by Np the cardinality of Ep(𝔽p), where 𝔽p is a finite field of p elements. Then for any δ > 0, the set of primes p for which Np has a divisor in the range (pδ - ∊(p), pδ + ∊(p)) has density zero. Moreover, the set of primes p for which [Formula: see text] has density zero.
SINGLE CELL IMAGING OF BAX TRANSLOCATION DURING APOPTOSIS INDUCED BY PHOTOFRIN-PDT
Authors: ZHOU FEIFAN , XING DA , CHEN WEI R.
Published: May 2009

Apoptosis is an important cellular event that plays a key role in the therapy of many diseases. The mechanism of the initiation and regulation of photodynamic therapy (PDT)–induced apoptosis is complex. Our previous study found that Photofrin was localized primarily in mitochondria, the primary targets of Photofrin-PDT. The key role of Bax in the mitochondria-mediated apoptosis has been demonstrated in many systems. In order to determine the role of Bax in the mitochondrion-mediated apoptosis induced by Photofrin-PDT, we used the GFP-Bax plasmid to monitor the dynamics of Bax activation after PDT treatment. With laser scanning confocal microscopy, we found that Bax did not translocate from the cytosol to mitochondria when the mitochondrial membrane potential (ΔΨm) disappeared, measured by TMRM. Thus, for Photofrin-PDT, the commitment to cell death is independent of Bax activation.
MONTE CARLO SIMULATION OF POLARIZED LIGHT SCATTERING IN TISSUES
Authors: YUN TIANLIANG , LI WEI , JIANG XIAOYU , MA HUI
Published: May 2009

We investigate the propagation of polarized light in fibrous tissues such as muscle and skin. The myofibrils and collagen fibers are approximated as long cylinders and the tissue phantom is composed of spherical and cylindrical structures. We apply Monte Carlo method based on this phantom to simulate and analyze polarization imaging process of muscle. The good agreement between the simulation results and the experimental results validate the assumption of the phantom composition. This paper also presents how to describe the fiber orientation distribution and tissue anisotropy according to three parameters derived from the polarization imaging.
SPECTRAL IMAGING AND ANALYSIS TO YIELD TISSUE OPTICAL PROPERTIES
Authors: JACQUES STEVEN L.
Published: May 2009

An introduction to the basics of spectral imaging as applied to biological tissues is presented. An example of a spectral image of a face is used to demonstrate the data and spectral analysis that specify the melanin content (M), blood content (B), tissue oxygen saturation (S), water content (W), fraction of scattering due to Rayleigh scattering (f) and due to Mie scattering (1 - f), and the reduced scattering coefficient at 500-nm wavelength (μ′s 500 nm). The sensitivity of reflectance spectra to variation in the various parameters is illustrated.
Robust result merging using sample-based score estimates
Authors: Shokouhi Milad , Zobel Justin
Published: May 2009

In federated information retrieval, a query is routed to multiple collections and a single answer list is constructed by combining the results. Such metasearch provides a mechanism for locating documents on the hidden Web and, by use of sampling, can proceed even when the collections are uncooperative. However, the similarity scores for documents returned from different collections are not comparable, and, in uncooperative environments, document scores are unlikely to be reported. We introduce a new merging method for uncooperative environments, in which similarity scores for the sampled documents held for each collection are used to estimate global scores for the documents returned per query. This method requires no assumptions about properties such as the retrieval models used. Using experiments on a wide range of collections, we show that in many cases our merging methods are significantly more effective than previous techniques.
SEA
Authors: Candan K. Selçuk , Dönderler Mehmet E. , Hedgpeth Terri , Kim Jong Wook , Li Qing , Sapino Maria Luisa
Published: May 2009

While navigation within complex information spaces is a problem for all users, the problem is most evident with individuals who are blind who cannot simply locate, point, and click on a link in hypertext documents with a mouse. Users who are blind have to listen searching for the link in the document using only the keyboard and a screen reader program, which may be particularly inefficient in large documents with many links or deep hierarchies that are hard to navigate. Consequently, they are especially penalized when the information being searched is hidden under multiple layers of indirections. In this article, we introduce a
segment-enrich-annotate
(SEA) paradigm for adapting digital content with deep structures for improved accessibility. In particular, we instantiate and evaluate this paradigm through the iCare-Assistant, an assistive system for helping students who are blind in accessing Web and electronic course materials. Our evaluations, involving the participation of students who are blind, showed that the iCare-Assistant system, built based on the SEA paradigm, reduces the navigational overhead significantly and enables user who are blind access complex online course servers effectively.
Bounded coordinate system indexing for real-time video clip search
Authors: Huang Zi , Shen Heng Tao , Shao Jie , Zhou Xiaofang , Cui Bin
Published: May 2009

Recently, video clips have become very popular online. The massive influx of video clips has created an urgent need for video search engines to facilitate retrieving relevant clips. Different from traditional long videos, a video clip is a short video often expressing a moment of significance. Due to the high complexity of video data, efficient video clip search from large databases turns out to be very challenging. We propose a novel video clip representation model called the
Bounded Coordinate System
(BCS), which is the first single representative capturing the dominating content and content—changing trends of a video clip. It summarizes a video clip by a coordinate system, where each of its coordinate axes is identified by principal component analysis (PCA) and bounded by the range of data projections along the axis. The similarity measure of BCS considers the operations of translation, rotation, and scaling for coordinate system matching. Particularly, rotation and scaling reflect the difference of content tendencies. Compared with the quadratic time complexity of existing methods, the time complexity of measuring BCS similarity is linear. The compact video representation together with its linear similarity measure makes real-time search from video clip collections feasible. To further improve the retrieval efficiency for large video databases, a two-dimensional transformation method called
Bidistance Transformation
(BDT) is introduced to utilize a pair of optimal reference points with respect to bidirectional axes in BCS. Our extensive performance study on a large database of more than 30,000 video clips demonstrates that BCS achieves very high search accuracy according to human judgment. This indicates that content tendencies are important in determining the meanings of video clips and confirms that BCS can capture the inherent moment of video clip to some extent that better resembles human perception. In addition, BDT outperforms existing indexing methods greatly. Integration of the BCS model and BDT indexing can achieve real-time search from large video clip databases.
Resiliency Policies in Access Control
Authors: Li Ninghui , Wang Qihua , Tripunitara Mahesh
Published: May 2009

We introduce the notion of resiliency policies in the context of access control systems. Such policies require an access control system to be resilient to the absence of users. An example resiliency policy requires that upon removal of any
s
users, there should still exist
d
disjoint sets of users such that the users in each set together possess certain permissions of interest. Such a policy ensures that even when emergency situations cause some users to be absent, there still exist independent teams of users that have the permissions necessary for carrying out critical tasks. The Resiliency Checking Problem determines whether an access control state satisfies a given resiliency policy. We show that the general case of the problem and several subcases are intractable (
NP
-hard), and identify two subcases that are solvable in linear time. For the intractable cases, we also identify the complexity class in the polynomial hierarchy to which these problems belong. We discuss the design and evaluation of an algorithm that can efficiently solve instances of nontrivial sizes that belong to the intractable cases of the problem. Furthermore, we study the consistency problem between resiliency policies and static separation of duty policies. Finally, we combine the notions of resiliency and separation of duty to introduce the resilient separation of duty policy, which is useful in situations where both fault-tolerance and fraud-prevention are desired.
IP Covert Channel Detection
Authors: Cabuk Serdar , Brodley Carla E. , Shields Clay
Published: May 2009

A covert channel can occur when an attacker finds and exploits a shared resource that is not designed to be a communication mechanism. A network covert channel operates by altering the timing of otherwise legitimate network traffic so that the arrival times of packets encode confidential data that an attacker wants to exfiltrate from a secure area from which she has no other means of communication. In this article, we present the first public implementation of an IP covert channel, discuss the subtle issues that arose in its design, and present a discussion on its efficacy. We then show that an IP covert channel can be differentiated from legitimate channels and present new detection measures that provide detection rates over 95%. We next take the simple step an attacker would of adding noise to the channel to attempt to conceal the covert communication. For these noisy IP covert timing channels, we show that our online detection measures can fail to identify the covert channel for noise levels higher than 10%. We then provide effective offline search mechanisms that identify the noisy channels.
Micromedicine to the rescue
Authors: Monroe Don
Published: May 2009

Medical researchers have long dreamed of "magic bullets" that go directly where they are needed. With micromedicine, this dream could become a life-saving reality.
Autonomous helicopters
Authors: Goth Gregory
Published: May 2009

Researchers are improving unmanned helicopters' capabilities to address regulatory requirements and commercial uses.
The profession of ITBeyond computational thinking
Authors: Denning Peter J.
Published: May 2009

If we are not careful, our fascination with "computational thinking" may lead us back into the trap we are trying to escape.
Inside risksReducing risks of implantable medical devices
Authors: Fu Kevin
Published: May 2009

A prescription to improve security and privacy of pervasive health care.