bluuebunny/crossref_metadata_2025 huggingface dataset:
Scalable uncertainty estimation for nonlinear inverse problems using parameter reduction, constraint mapping, and geometric sampling: Marine controlled-source electromagnetic examples
Authors: Tompkins Michael J. , Fernández Martínez Juan L. , Alumbaugh David L. , Mukerji Tapan
Published: June 2011

We have developed a new uncertainty estimation method that accounts for nonlinearity inherent in most geophysical problems, allows for the explicit search of model posterior space, is scalable, and maintains computational efficiencies on the order of deterministic inverse solutions. We accomplish this by combining an efficient parameter reduction technique, a parameter constraint mapping routine, a sparse geometric sampling scheme, and an efficient forward solver. In order to reduce our model domain and determine an independent basis, we implement both a typical principal component analysis, which factorizes the model covariance matrix, and an alternative compression method, based on singular-value decomposition, which acts on training models, directly, and is storage efficient. Once we have a reduced base, we map parameter constraints, from our original model domain, to this reduced domain to define a bounded geometric region of feasible model space. We utilize an optimal scheme to sample this reduced model space that uses Smolyak sparse grids and minimizes the number of forward solves by finding the sparsest sampling required to produce convergent uncertainty measures. The result is an ensemble of equivalent models, consistent with our inverse solution structure, which is used to infer inverse uncertainty. We tested our method with a 1D synthetic example, a comparison with a published Metropolis-Hastings sampling example, and an extension to 2D problems using a field data inversion.
High-frequency signals from air-gun arrays
Authors: Landrø M. , Amundsen L. , Barker D.
Published: June 2011

We suggest two different mechanisms for generation of high-frequency signals from seismic sources: one type that we interpret as being caused by high-frequency effects close to and within each individual air gun and another type caused by an effect that we refer to as ghost cavitation. The former one is found to have a steep decreasing amplitude trend with frequency, while the latter has a close to 1/f attenuation for frequencies above 1 kHz. A thorough understanding of the effects is of significant importance to quantify and estimate any environmental impact of marine seismic air-gun arrays. The proposed ghost-cavitation mechanism needs further experimental testing. However, given that the suggested model is proven, we think it is possible to attenuate the high-frequency noise generated by compact air-gun arrays by increasing the areal extent of the gun array.
Creativity and mental disorder: Family study of 300 000 people with severe mental disorder
Authors: Kyaga Simon , Lichtenstein Paul , Boman Marcus , Hultman Christina , Långström Niklas , Landén Mikael
Published: June 2011

Background

There is a long-standing belief that creativity is coupled with psychopathology.

Aims

To test this alleged association and to investigate whether any such association is the result of environmental or genetic factors.

Method

We performed a nested case–control study based on Swedish registries. The likelihood of holding a creative occupation in individuals who had received in-patient treatment for schizophrenia, bipolar disorder or unipolar depression between 1973 and 2003 and their relatives without such a diagnosis was compared with that of controls.

Results

Individuals with bipolar disorder and healthy siblings of people with schizophrenia or bipolar disorder were overrepresented in creative professions. People with schizophrenia had no increased rate of overall creative professions compared with controls, but an increased rate in the subgroup of artistic occupations. Neither individuals with unipolar depression nor their siblings differed from controls regarding creative professions.

Conclusions

A familial cosegregation of both schizophrenia and bipolar disorder with creativity is suggested.
Symmetry breaking in mouse oocytes requires transient F-actin meshwork destabilization
Authors: Azoury Jessica , Lee Karen Wingman , Georget Virginie , Hikal Pascale , Verlhac Marie-Hélène
Published: June 2011

Female meiotic divisions are extremely asymmetric, giving rise to a large oocyte and small degenerating polar bodies, keeping the maternal stores for further embryo development. This asymmetry is achieved via off-center positioning of the division spindle. Mouse oocytes have developed a formin-2-dependent actin-based spindle positioning mechanism that allows the meiotic spindle to migrate towards the closest cortex. Using spinning disk microscopy and FRAP analysis, we studied the changes in the organization of the cytoplasmic F-actin meshwork during the first meiotic division. It is very dense in prophase I, undergoes a significant density drop upon meiosis resumption and reforms progressively later on. This meshwork remodeling correlates with endogenous formin 2 regulation. High formin 2 levels at meiosis I entry induce meshwork maintenance, leading to equal forces being exerted on the chromosomes, preventing spindle migration. Hence, the meshwork density drop at meiosis resumption is germane to the symmetry-breaking event required for successful asymmetric meiotic divisions.
The Impact of Yield-Dependent Trading Costs on Pricing and Production Planning Under Supply Uncertainty
Authors: Kazaz Burak , Webster Scott
Published: June 2011

This paper studies the role of the yield-dependent trading cost structure influencing the optimal choice of the selling price and production quantity for a firm that operates under supply uncertainty in the agricultural industry. The firm initially leases farm space, but its realized amount of fruit supply fluctuates because of weather conditions, diseases, etc. At the end of the growing season, the firm has three options: convert its crop supply to the final product, purchase additional supplies from other growers, and sell some (or all) of its crop supply in the open market without converting to the finished product. We consider the problem both from a risk-neutral and a risk-averse perspective with varying degrees of risk aversion. The paper offers three sets of contributions: (1) It shows that the use of a static cost exaggerates the initial investment in the farm space and the expected profit significantly, and the actual value gained from a secondary (emergency) option for an agricultural firm is lower under the yield-dependent cost structure. (2) It proves that although the risk-neutral firm does not benefit from fruit futures, a sufficiently risk-averse firm can benefit from the presence of a fruit futures market. The same risk-averse firm does not purchase fruit futures when it operates under static costs. Thus, fruit futures can only add value under yield-dependent trading costs. (3) Contrary to the results presented for the newsvendor problem under demand uncertainty, the firm does not always commit to a lower initial quantity (leased farm space) under risk aversion. Rather, the firm might lease a larger farm space under risk aversion.
Incorporation of iodate into uranyl borates and its implication for the immobilization of 129I in nuclear waste repositories
Authors: Wu Shijun , Wang Shuao , Simonetti Antonio , Chen Fanrong , Albrecht-Schmitt Thomas E.
Published: June 2011

A series of uranyl borates, UO2B2O4, Na[(UO2)B6O10(OH)]3· 2H2O, and K2[(UO2)2B12O19(OH)4]·0.3H2O, with different topologies have been prepared and tested for the incorporation of iodate, one of the chemical forms that 129I should have in nuclear waste. Laser ablation ICP-MS was used to determine the iodine content in single crystals of the three different uranyl borates. Iodine levels can be greater than 3200 ppm in crystals synthesized in the presence of iodate. The intercalation of iodic acid is one possible mechanism for iodate uptake in these solids.
Synthesis, crystal structure and spectroscopic properties of Y3O2Cl[SeO3]2 : Eu3+
Authors: Zitzer Sabine , Schleifenbaum Frank , Schleid Thomas
Published: June 2011

The yttrium oxide chloride oxoselenate(IV) Y3O2Cl[SeO3]2, doped with Eu3+ at 3% mass percentage, can be obtained by common solid-state reactions from Y2O3, Eu2O3, YCl3 and SeO2, and crystallizes isostrucäturally with the analogous terbium(III) compound Tb3O2Cl[SeO3]2. The orthorhombic crystal structure (Pnma, a = 548.24(4), b = 1457.92(9), c = 1102.83(7) pm and Z = 4 for undoped yttrium samples) was identified by single-crystal X-ray diffraction data and the purity of the product was checked with powder XRD methods. The presence of isolated pyramidal [SeO3]2– units could be confirmed by Raman spectroscopy. The optical band gap was determined by diffuse reflectance spectroscopy (DRS) applying the Kubelka-Munk function. Fluorescence spectroscopy measurements revealed the prominent f → f-transitions for Eu3+-doped compounds in both the excitation and the emission spectra of Y3O2Cl[SeO3]2 : Eu3+.
Safety of gastrointestinal endoscopy during pregnancy
Authors: Taller András
Published: June 2011

There are only few data of gastrointestinal endoscopy in pregnant patients. Only 0.4% of all procedures are carried out during pregnancy. Case reports and some small retrospective studies are available. Because of physiological changes in pregnancy there might be special risks of endoscopy. There might be complaints which can be physiologic during pregnancy, but can be signs of gastrointestinal disorders, too. Therefore, indications for endoscopy are not always clear and easy. Safety of the procedures is also not well studied. Besides the risks of endoscopy, medication given to the mother, electrocoagulation and radiation exposure from fluoroscopy during endoscopic retrograde cholangiopancreatography might be harmful to the fetus. Endoscopy should only be done when indication is unquestionable and strong. Only FDA „A” and „B” category medication is allowed. Gastroscopy is necessary for bleeding and for patients with pyrosis going together with alarm signs. Nausea, vomiting, abdominal pain and fecal occult blood test positivity are not indications for endoscopy, only for gastroenterogical consultation. Sigmoidoscopy is recommended for indication of lower gastrointestinal bleeding and sigmoid or rectal mass. Only therapeutic endoscopic retrograde cholangiopancreatography should be performed. Obstructive jaundice and biliary pancreatitis need immediate endoscopic intervention. The fetus must be shielded from radiation exposure. Orv. Hetil., 2011, 152, 1043–1051.
Property Rights over Money: the Italian Perspective and English Law
Authors: Caggiano Ilaria Amelia
Published: June 2011

The work considers money in a different way depending on whether it is used as a means of payment or for other functions. Only in the first case it comes to evidence a characteristic proprietary regime which cuts across the different categories of property by which money assets are represented. In the other cases, money should be considered simply as a fungible asset. However, rules of specification of fungibles should be reconsidered. Specifically, the paper deals with the issues arising in transactions where money is transferred to an intermediary for management. It aims to show that the transferor or the beneficiary keeps real interests in the money transferred. It argues how these interests may be relevant to Italian law, by comparing it with the English legal system. The paper demonstrates that reference to property law may be useful for evaluating the quantum of rights of the transferor of money by referring to the concept of value and by the analysis of law of mixtures under the Italian and the English law. The analysis is worked out in terms of corporeal money but argues that law reaches equivalent outcomes for incorporeal money in the field under consideration.
AMMI analysis of nitrogen harvest index in bread wheat
Authors: Gorjanovic Biljana , Kraljevic-Balalic Marija
Published: June 2011

Nitrogen harvest index - NHI is a measure of efficiency of nitrogen
translocation from vegetative organs to grain. The goal of this paper is to
investigate variability and stability of nitrogen harvest index of twelve
bread wheat genotypes, on three nitrogen levels. ANOVA showed that nitrogen
harvest index was mostly under influence of the year x genotype interaction,
year of investigation and genotype, and in the smallest amount of the
nitrogen rate. Increasing doses of nitrogen did not lead to increased
nitrogen harvest index. AMMI analysis showed that most genotypes differed in
both the main effect and in GxE interaction. The highest stability i.e. the
smallest interaction effect, was found in varieties Axis, Ilona, Sonata and
Renan on N0 rate, and in varieties Malyska, Petrana, Axis and Evropa 90 on
N100 rate. Cultivar Pobeda with the high average values for nitrogen harvest
index, also had small interaction effect, i.e. it proved to be a stable
variety.
Studies on the optimal extraction of flavonoids from the fruit of Juniperus virginiana L.
Authors: Trifunci Svetlana , Ardelean Dorina
Published: June 2011

The isolation and quantitative determination of flavonoid compounds in fruit
of Juniperus virginiana L. (Cupressaceae) are described. A method for the
detection of those flavonoids was high performance liquid chromatography
(HPLC). Rutin and kaempferol were determined in accordingly extracts and
quercetin only in hydrolysated extracts.
Researching the Powerful: Seeking Knowledge about Policy
Authors: Ozga Jenny
Published: June 2011

This article introduces the articles in the collection on ‘Researching the Powerful’ by providing some background on the project ‘Knowledge and Policy’ which gave rise to the research on which the articles are based. It also offers some reflections on the ‘work of construction’ of research, with particular attention to the ways in which policy elites, which are the main focus of the research processes described and discussed in the articles that follow, seek to control, manipulate and manage the research process. This article draws attention to a finding reported in many of the articles in this special edition — namely, that this work of construction that policy makers do becomes in itself a source of knowledge about policy.
Enigmatic morphological disparity in tarsometatarsi of giant penguins from the Eocene of Antarctica
Authors: Hospitaleche Carolina , Jadwiszczak Piotr
Published: June 2011

Enigmatic morphological disparity in tarsometatarsi of giant penguins from the Eocene of Antarctica

The only record of the Paleogene Antarctic Sphenisciformes comes from the Eocene La Meseta Formation (Seymour Island, Antarctic Peninsula). The analysis of tarsometatarsi attributed to the genus Anthropornis ("giant" penguins) from the Argentine, Polish and Swedish collections revealed an intriguing heterogeneity within these taxonomically important elements of the skeleton. The unique hypotarsal morphology challenges the current systematics of large-bodied penguins and sheds new light on their evolution.
Slosh-Free Positioning of Containers with Liquids and Flexible Conveyor Belt
Authors: Hubinský Peter , Pospiech Thomas
Published: June 2011

Slosh-Free Positioning of Containers with Liquids and Flexible Conveyor Belt

This paper describes a method for slosh-free moving of containers with a liquid at which the conveyor belt is flexible. It shows, by means of experimental results, that a container filled with a liquid can be regarded as a damped pendulum. Upon parameter identification of the two single-mode subsystems, theoretical modelling of the complete system is described. With respect to industrial application, feedforward control is used to transfer the container in horizontal direction without sloshing. The applied method requires deterministic and hard real time communication between the PLC and the servo amplifier which is realized here with Ethernet POWERLINK. The principle structure, calculations, time duration and the robustness of the basic types of input shaper are described and compared with each other. Additionally the positioning results of the two-mode system are presented. Finally, a possibility of the principle software implementation is presented.
Influence of Radiation on the Dielectric Properties of XLPE Based Insulation Systems
Authors: Ďurman Vladimír , Lelák Jaroslav
Published: June 2011

Influence of Radiation on the Dielectric Properties of XLPE Based Insulation Systems

The paper discusses the possibilities of acquiring and processing the dielectric data in the range of very low frequency (VLF) and also design and construction of an impedance analyzer for measurements in this frequency range. The impedance measurements in the VLF range were used for investigation of the influence of radiation on the cross-linked polyethylene cable dielectric. An expressive β-type relaxation process was found in this type of cable. Most of the dielectric response parameters of the process depend significantly on the absorbed dose of radiation. The analysis of the process parameters showed that the most probable reason of the structural changes in cross-linked polyethylene was additional cross-linking. The results also proved that the impedance measurements in the VLF range could be effectively used in practice for estimation of the absorbed dose in the cross-linked polyethylene cables stressed by radiation.t data only. In order to identify or classify motion, data processing in real time is needed.
Field-Driven Brownian Motion of Magnetic Domain Walls
Authors: Glod Lukáš , Vasziová Gabriela , Tóthová Jana , Lisý Vladimír
Published: June 2011

Field-Driven Brownian Motion of Magnetic Domain Walls

The dynamics of a magnetic domain wall (DW) in a wire is studied. The DW is modeled as a Brownian particle subjected to thermal fluctuations and is characterized by the mass, position and velocity. Its motion is damped by friction, pinned by the irregularities in the material and driven by a constant force due to the external magnetic field. We have obtained the corresponding Langevin equation that contains a white-noise force. The use of an effective method taken from the statistical physics allowed us to convert this stochastic equation into an ordinary differential equation. From its solution the mean square displacement of the DW with other relevant time correlation functions and their spectral densities have been found. The electric current induced by the moving DW is also calculated.
Switching Magnetization Magnetic Force Microscopy — An Alternative to Conventional Lift-Mode MFM
Authors: Cambel Vladimír , Gregušová Dagmar , Eliáš Peter , Fedor Ján , Kostič Ivan , Maňka Ján , Ballo Peter
Published: June 2011

Switching Magnetization Magnetic Force Microscopy — An Alternative to Conventional Lift-Mode MFM

In the paper we present an overview of the latest progress in the conventional lift-mode magnetic force microscopy (MFM) technique, achieved by advanced MFM tips and by lowering the lift height. Although smaller lift height offers improved spatial resolution, we show that lowered tip-sample distance mixes magnetic, atomic and electric forces. We describe an alternative to the lift-mode procedure - Switching Magnetization Magnetic Force Microscopy [SM-MFM], which is based on two-pass scanning in tapping mode AFM with reversed tip magnetization between the scans. We propose design and calculate the magnetic properties of such SM-MFM tips. For best performance the tips must exhibit low magnetic moment, low switching field, and single-domain state at remanence. The switching field of such tips is calculated for Permalloy hexagons.
Gadolinium Scandate: Next Candidate for Alternative Gate Dielectric in CMOS Technology?
Authors: Fröhlich Karol , Fedor Ján , Kostič Ivan , Maňka Ján , Ballo Peter
Published: June 2011

Gadolinium Scandate: Next Candidate for Alternative Gate Dielectric in CMOS Technology?

The films of GdScO3were prepared by liquid injection metal-organic chemical vapor deposition, MOCVD at 600 °C on (100) Si substrate. The as-deposited films were amorphous with a smooth surface and sharp GdScO3/Si interface. X-ray diffraction showed that the amorphous phase is well preserved upon rapid thermal annealing up to 1000 °C. It is shown, that exact stoichiometry of GdScO3is not necessary to achieve dielectric constant above 20.
Prediction Methods for MPEG-4 and H.264 Video Transmission
Authors: Pilka Filip , Oravec Miloš
Published: June 2011

Prediction Methods for MPEG-4 and H.264 Video Transmission

Video services became a large part of internet network traffic. Therefore understanding of video coding standards and video traffic sources, such as video trace files is highly important. In this paper we concentrate on the basic characteristics of mpeg-4 and h.264 video coding standards. We describe the concept of the i, p and b frames in these standards since they are the main feature of every video trace file. Then we describe the content of the video trace files since the trace files are important for researchers to investigate network performance and understanding of network features. These are the important issues in terms of assuring the quality of service (QoS) in multimedia applications spread across the internet. Traffic prediction and bandwidth allocation are the crucial parts in terms of QoS. In this kind of applications, the artificial neural networks are vastly used. Therefore we illustrate the results of neural networks for video traffic prediction using both mpeg-4 and h.264 trace files.
Storage Phosphors for Medical Imaging
Authors: Leblans Paul , Vandenbroucke Dirk , Willems Peter
Published: June 2011

Computed radiography (CR) uses storage phosphor imaging plates for digital imaging. Absorbed X-ray energy is stored in crystal defects. In read-out the energy is set free as blue photons upon optical stimulation. In the 35 years of CR history, several storage phosphor families were investigated and developed. An explanation is given as to why some materials made it to the commercial stage, while others did not. The photo stimulated luminescence mechanism of the current commercial storage phosphors, BaFBr:Eu2+ and CsBr:Eu2+ is discussed. The relation between storage phosphor plate physical characteristics and image quality is explained. It is demonstrated that the morphology of the phosphor crystals in the CR imaging plate has a very significant impact on its performance.
Food Intake and Dietary Glycaemic Index in Free-Living Adults with and without Type 2 Diabetes Mellitus
Authors: McGeoch Susan C. , Holtrop Grietje , Fyfe Claire , Lobley Gerald E. , Pearson Donald W. M. , Abraham Prakash , Megson Ian L. , MacRury Sandra M. , Johnstone Alexandra M.
Published: June 2011

A recent Cochrane review concluded that low glycaemic index (GI) diets are beneficial in glycaemic control for patients with type 2 diabetes mellitus (T2DM). There are limited UK data regarding the dietary GI in free-living adults with and without T2DM. We measured the energy and macronutrient intake and the dietary GI in a group (n = 19) of individuals with diet controlled T2DM and a group (n = 19) without diabetes, matched for age, BMI and gender. Subjects completed a three-day weighed dietary record. Patients with T2DM consumed more daily portions of wholegrains (2.3 vs. 1.1, P = 0.003), more dietary fibre (32.1 vs. 20.9 g, P < 0.001) and had a lower diet GI (53.5 vs. 57.7, P = 0.009) than subjects without T2DM. Both groups had elevated fat and salt intake and low fruit and vegetable intake, relative to current UK recommendations. Conclusions: Patients with T2DM may already consume a lower GI diet than the general population but further efforts are needed to reduce dietary GI and achieve other nutrient targets.
THE STUDY ON VENTURE INVESTMENT EVALUATION BASED ON LINGUISTIC VARIABLES FOR CHINESE CASE / ĮMONĖS INVESTICIJŲ VERTINIMO TYRIMAS KINIJOS PAVYZDŽIU
Authors: Liu Peide
Published: June 2011

The venture investment evaluation plays a very important role in the venture investment operation process. The goal of the paper is development of evaluation index systems and evaluation methods for venture investment. Firstly, the evaluation index systems of venture investment project are constructed in accordance with China's practical situation. Then evaluation models have been presented. In the models, operational laws of linguistic variables and distance of two linguistic variables are defined; and a single objective optimization model is constructed by maximizing deviation method to get the objective weights of indexes, and alternatives are ranked by TOPSIS and grey relation methods respectively. Finally, a numerical example is given to illustrate the evaluation procedures of two approaches. The case shows that two different approaches get the same result, but TOPSIS is simpler apparently.

Santrauka

Šiame straipsnyje analizuojama, kokią įtaką turi įmonės investicijų vertinimas visam investavimo procesui. Šiam tikslui pasiekti autorius pasirinko vertinimo indeksų sistemą ir investicijų vertinimo rizikos metodus. Pirmąjį pasirinktą instrumentą, t. y. vertinimo indeksų sistemą, autorius naudoja analizuodamas ir atlikdamas Kinijoje vykdomų investicinių projektų vertinimo tyrimą. Kitus tyrimo instrumentus ir matematinius metodus, tokius kaip TOPSIS, Grey metodas ir pan., taiko apibendrindamas gautus rezultatus.
De l'humanitaire imparfait
Authors: Pandolfi Mariella , Corbet Alice
Published: June 2011

Résumé L’article retrace les origines, en Amérique du Nord et en Europe, d’un des courants du débat critique sur l’humanitaire. La biopolitique de Foucault et d’Agamben, l’anthropologie médicale critique, les nouvelles perspectives d’une anthropologie du politique, la généalogie critique du développement et la prise de parole des acteurs humanitaires, deviennent les pistes d’une réflexion plus complexe proposée par les deux auteures engagées sur des terrains de recherche paradigmatiques pour tracer les limites de l’humanitaire.
Où est passée la « Reef Girl » ?
Authors: Maillot Adolphe
Published: June 2011

Résumé L’univers médiatique du surf contemporain est peuplé de créatures de rêve. Sur les pages des magazines spécialisés, elles accompagnent de leurs courbes voluptueuses les prouesses des surfeurs et les produits du surfwear , donnant à la lecture sportive une touche d’érotisme. Ces jeunes femmes à la divine plastique, qui font aussi partie de la réalité des plages, sont appelées beachgirls . La plus sexy d’entre elles est la «  Reef Girl  », pin-up « exotique » sans visage qui a contribué au succès de la marque de tongs Reef. Cet article se propose d’esquisser le portrait de cette figure féminine de la surf culture , et de retracer son parcours médiatique – narratif – avant sa récente disparition suite à l’essor de la mixité au sein d’une pratique physique à dominante masculine.
Blanchiment, soupçon et sécurité financière
Authors: Pereira Brigitte
Published: June 2011

Le blanchiment de capitaux est devenu une préoccupation majeure, celle-ci trouvant actuellement une nouvelle expression à travers l’accroissement des instruments de prévention. En effet, on assiste aujourd’hui à une approche préventive par les risques qui consiste à déclarer tout soupçon avec la possibilité de blocage de l’opération financière visée. Or le soupçon est, à présent, défini d’une manière étendue de telle sorte que la lutte préventive matérialise une forme d’insécurité financière susceptible de viser des opérations régulières. Certes, le système répressif est insuffisant et doit être accompagné d’une approche préventive visant à la fois les obligations de vigilance et de déclaration de soupçon incombant aux professionnels assujettis. Néanmoins, la problématique actuelle met en évidence la nécessité de rechercher un équilibre avec d’autres intérêts en présence comme la liberté d’investissement, le secret bancaire, le droit à la non-ingérence dans les affaires. De plus, cette extension de la prévention contre le blanchiment qui fait de tous les acteurs économiques de véritables agents anti-blanchiment conduit à des disparités en matière de coopération internationale.
Trophic relationships between the jumbo squid (Dosidicus gigas) and the lightfish (Vinciguerria lucetia) in the Humboldt Current System off Peru
Authors: Rosas-Luis Rigoberto , Tafur-Jimenez Ricardo , Alegre-Norza Ana R. , Castillo-Valderrama Pedro R. , Cornejo-Urbina Rodolfo M. , Salinas-Zavala Cesar A. , Sánchez Pilar
Published: June 2011

Acoustic surveys for assessing the biomass and distribution of the jumbo squid (Dosidicus gigas) and the lightfish (Vinciguerria lucetia) were carried out in the Humboldt Current System of Peru in 2007 and 2008. At the same time, 937 jumbo squid were caught and their stomach contents analyzed. The diet of the jumbo squid was dominated by mesopelagic fish. The first component of their fish diet was V. lucetia and the second component was the myctophid fish Diogenichthys laternatus. Acoustic biomass estimates of these species show that V. lucetia is an important component in aggregative structures in the Humboldt Current System of Peru and its distribution and movements are closely related to the migratory movements of the jumbo squid. The trophic relationship observed between D. gigas and V. lucetia promotes an increase in jumbo squid biomass and, has a positive trophic effect on the ocean ecosystem.
Experimental fossilisation of viruses from extremophilic Archaea
Authors: Orange F. , Chabin A. , Gorlas A. , Lucas-Staat S. , Geslin C. , Le Romancer M. , Prangishvili D. , Forterre P. , Westall F.
Published: June 2011

Abstract. The role of viruses at different stages of the origin of life has recently been reconsidered. It appears that viruses may have accompanied the earliest forms of life, allowing the transition from an RNA to a DNA world and possibly being involved in the shaping of tree of life in the three domains that we know presently. In addition, a large variety of viruses has been recently identified in extreme environments, hosted by extremophilic microorganisms, in ecosystems considered as analogues to those of the early Earth. Traces of life on the early Earth were preserved by the precipitation of silica on the organic structures. We present the results of the first experimental fossilisation by silica of viruses from extremophilic Archaea (SIRV2 – Sulfolobus islandicus rod-shaped virus 2, TPV1 – Thermococcus prieurii virus 1, and PAV1 – Pyrococcus abyssi virus 1). Our results confirm that viruses can be fossilised, with silica precipitating on the different viral structures (proteins, envelope) over several months in a manner similar to that of other experimentally and naturally fossilised microorganisms. This study thus suggests that viral remains or traces could be preserved in the rock record although their identification may be challenging due to the small size of the viral particles.
A handy new design paradigm
Authors: Bergelin B. , Slaboch B. , Sun J. , Voglewede P. A.
Published: June 2011

Abstract. In light of technological advances, researchers have lost sight of robotic grippers/end effectors design intent. In a semi-structured environment the biomimetic approach is impractical due to the high complexity of the mechanism and control algorithms. Current industrial grippers are robust, but lack the flexibility that allows for in hand manipulation. The authors believe that underactuated grippers provide the best approach to allow for in hand manipulation along with being rugged enough for an industrial setting. Thinking of the robotic gripper and the robotic arm as one system (as opposed to two separate subsystems), one is capable of using the degrees of freedom of the robot in conjunction with that of the gripper to provide the desired motion profile without the complexity of running two subsystems. This paper will outline where recent grippers have failed and will introduce a new design paradigm for grippers along with several underactuated gripper ideas. This paper was presented at the IFToMM/ASME International Workshop on Underactuated Grasping (UG2010), 19 August 2010, Montréal, Canada.
Static model for a 3-DOF underactuated finger
Authors: Guay F. , Gosselin C.
Published: June 2011

Abstract. This paper introduces a static model of a three-degree-of-freedom underactuated finger. The model includes all static forces, namely actuation forces, return forces and gravity. All geometric and static parameters can be freely changed (pulley radius, member's mass, etc.). Hence, the model allows complete static simulations to be performed and it can also be used for numerical optimization. This paper was presented at the IFToMM/ASME International Workshop on Underactuated Grasping (UG2010), 19 August 2010, Montréal, Canada.
Gold catalyst initiated growth of GaN nanowires by MOCVD
Authors: Ahl J.‐P. , Behmenburg H. , Giesen C. , Regolin I. , Prost W. , Tegude F. J. , Radnoczi G. Z. , Pécz B. , Kalisch H. , Jansen R. H. , Heuken M.
Published: June 2011

Our study shows the impact of the process parameters V/III ratio, pressure and temperature on growth and morphology of GaN nanowires (NWs) synthesized by an Au‐initiated vapour‐liquid‐solid mechanism on a sapphire substrate. We confined a temperature window for successful GaN NW growth and show how the variation of reactor pressure changes the NW morphology. Using a very low V/III ratio, NW tapering, which was observed for higher V/III ratios, could be avoided. The optimization of these process parameters led to non‐tapered GaN NWs, aligned perpendicular to the substrate. Further evaluation by scanning electron microscopy showed a high density (∼3·109/cm2) of hexagonal c‐plane GaN NWs having diameters of 60 ± 9 nm. Transmission electron microscopy revealed single‐crystalline NWs without threading dislocations but some stacking faults. The use of a very low V/III ratio was found to be important for the successful selective growth and, most interestingly, led to a difference in NW and gold catalyst droplet diameter. For chemical analysis of the NW and its catalyst droplet, electron energy loss spectroscopy was employed confirming gold as the catalyst material (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
High voltage operation of field‐plated AlInN HEMTs
Authors: Fareed Qhalid , Tarakji Ahmad , Dion Joseph , Islam Monirul , Adivarahan Vinod , Khan Asif
Published: June 2011

In this paper, we report for the first time, high voltage operations of field plated Al1–xInxN (x≈0.18) HEMTs. The epilayer structure of our devices consisted of AlInN/GaN HEMT structure with and without AlN cap layer. 1.25 μm gate‐length AlInN/GaN HEMT devices were then fabricated with 2 μm source‐gate distance using our baseline fabrication process. The gate‐drain spacing were varied from 6 (baseline) to 12 μm. The devices were field‐plated to analyze the breakdown voltage. The maximum drain current density in devices grown on sapphire substrates was around 1.2 A/mm (at a +3 V gate bias). Maximum transconductance was around 370 mS/mm. The insulating AlN cap layer, combined with the field‐plated gate design had proved to substantially improve the devices OFF‐state breakdown voltage. The measured breakdown voltage was as high as 350‐400 V. The results presented highlights the potentials of AlInN‐based devices for the high‐voltage and energy‐efficient power‐electronics applications (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Symplectic calculation of the outboard magnetic footprint from noise and error fields in the DIII-D
Authors: ALI HALIMA , PUNJABI ALKESH , NYAKU ERNEST
Published: June 2011

The backward symplectic DIII-D map and continuous symplectic analog of the map for magnetic field line trajectories in the DIII-D [10] (Luxon, J. L. and Davis, L. E. 1985 Fusion Technol.8, 441) in natural canonical coordinates are used to calculate the magnetic footprint on the outboard collector plate of the DIII-D tokamak from the field errors and internal topological noise. The equilibrium generating function for the DIII-D used in the map very accurately represents the magnetic geometry of the DIII-D. The step-size of the map is kept considerably small so that the magnetic perturbation added from symplectic discretization of the Hamiltonian equations of the magnetic field line trajectories is very small. The natural canonical coordinates allow inverting to the real physical space. The combination of highly accurate equilibrium generating function, natural canonical coordinates, symplecticity, and small step-size then together gives a very accurate calculation of magnetic footprint. Radial variation of magnetic perturbation and the response of plasma to perturbation are not included. The footprint is in the form of toroidally winding helical strips. The area of footprint scales as 1st power of amplitude. The physical parameters as toroidal angle, length, and poloidal angle covered before striking, and the safety factor all have fractal structure. The average field diffusion near X-point for lines that strike and that do not strike differs by about four orders of magnitude. The flux loss decreases for high values of amplitude of perturbation.
GEOMETRIC AND TOPOLOGICAL STRUCTURES RELATED TO M-BRANES II: TWISTED STRING AND STRINGCSTRUCTURES
Authors: SATI HISHAM
Published: June 2011

The actions, anomalies and quantization conditions allow theM2-brane and theM5-brane to support, in a natural way, structures beyond spin on their world-volumes. The main examples are twisted string structures. This also extends to twisted stringcstructures which we introduce and relate to twisted string structures. The relation of theC-field to Chern–Simons theory suggests the use of the string cobordism category to describe theM2-brane.
Using high-Tc superconducting resonator for enhancement of diffusion tensor imaging
Authors: Lin In-Tsang , Yang Hong-Chang , Chen Jyh-Horng
Published: June 2011

Here, a report on diffusion tensor imaging (DTI) using a 125.3 MHz high-temperature superconducting (HTS) surface resonator for magnetic resonance imaging (MRI) is presented. A 40 mm in diameter Bi2Sr2Ca2Cu3Ox (Bi-2223) tape surface resonator was built. Using a HTS surface resonator at 77 K than a similar copper surface resonator at 300 K, the capacity to save the accuracy of DTI in a reduced scan time (11 min) was demonstrated. The standard deviation of deviation angles of DTI fiber tracking was also improved by 2.5 gains. The use of HTS surface resonator may improve the reliability of fiber tracking experiments.
Hole transport mechanism in organic/inorganic hybrid system based on in-situ grown cadmium telluride nanocrystals in poly(3-hexylthiophene)
Authors: Khan Mohd Taukeer , Kaur Amarjeet , Dhawan S. K. , Chand Suresh
Published: June 2011

The present manuscript demonstrates the hole transport mechanism in an organic/inorganic hybrid system based on in-situ grown cadmium telluride (CdTe) nanocrystals in a poly(3-hexylthiophene) (P3HT) matrix. The increase of hole current in the hybrid system is correlated with the formation of a host-guest (P3HT-CdTe) charge transfer complex duly supported by photoluminescence quenching. The hole transport mechanism in P3HT is governed by a space charge limited current with temperature, carrier density, and field dependent mobility. Incorporation of CdTe nanocrystals in a polymer matrix results in enhancement in the value of trap density Hb from 2.8 × 1018 to 5.0 × 1018 cm−3 and reduction in activation energies from 52 meV to 11 meV. At high trap density, trap potential wells start overlapping; this results in decrease of activation energies.
Extraction of additional interfacial states of silicon nanowire field-effect transistors
Authors: Sato Soshi , Li Wei , Kakushima Kuniyuki , Ohmori Kenji , Natori Kenji , Yamada Keisaku , Iwai Hiroshi
Published: June 2011

Interfacial states of silicon nanowire field-effect transistors with rectangular-like cross-sections (wire height of 10 nm and widths of 9 and 18 nm) have been evaluated from the transfer characteristics in the subthreshold region measured at cryogenic temperatures, where kinks in the drain current becomes prominent. It is found that the kinks can be well-explained assuming local interfacial states near the conduction band (Ec). The main extracted local states have been shown to exist at 10 and 31 meV below Ec with the densities of 1.3×1013 cm−2/eV and 5.4×1012 cm−2/eV, respectively. By comparing two field-effect transistors with different wire widths, the former states can be assigned to the states located at the corner and the side surface of the wire, and the latter to the top and the bottom surfaces.
CHAOTIC CONTROL OF LIU SYSTEM WITH PERIODIC PARAMETRIC PERTURBATIONS
Authors: WANG XINGYUAN , WANG MINGJUN
Published: June 2011

In this paper, periodic parametric perturbations are used to control chaos in Liu system. By changing the frequency of the perturbation signal, Liu system can be guided to not only periodic motion but also hyperchaos. Phase diagram, bifurcation diagram, Lyapunov exponents spectrum and Poincáre map are used to analyze the dynamic behavior of the controlled system in the numerical simulations, which show the effectiveness of our method.
PROGRAMMABLE AND CONTROLLED REMOTE UNAMBIGUOUS QUANTUM-STATE DISCRIMINATION BASED ON NONLOCAL SYSTEM–ANCILLA CONDITIONAL ROTATION
Authors: CHEN LIBING , LIU YUHUA , LU HONG
Published: June 2011

We propose and prove a theoretical scheme of realizing programmable and controlled remote quantum-state unambiguous discrimination (UD) based on nonlocal system–ancilla unitary evolution. By decomposing the evolution process from the initial state to the final state, we first construct the required nonlocal unitary evolution, which is a nonlocal conditional rotation. Utilizing the entanglement property of Greenberger–Horne–Zeilinger (GHZ) class state, we then design a quantum network for implementing the controlled nonlocal conditional rotation gate, and thus provide a feasible physical means to realize the remote UD. The features of the scheme is that the particular pair of states of system (data register) that can be remotely and unambiguously discriminated is specified by the state of the ancilla (program register). Furthermore, a third side is included, who may participate the process of quantum remote implementation as a supervisor. When the quantum channel is partially entangled, the third one can rectify the state distorted by the imperfect quantum channel. The success probability of implementing this remote UD is also investigated.
TRANSPORT THROUGH INTERACTING AHARONOV–BOHM–CASHER INTERFEROMETERS
Authors: XU QING-QIANG , GAO BEN-LING , XIONG SHI-JIE
Published: June 2011

We investigate the transport properties of an interacting ring threaded by a magnetic flux and with Rashba spin-orbit coupling, based on a recently developed functional renormalized group technique. In the calculations of the electronic transport processes, the Coloumb On-site interactions are taken into account. For an interacting ring connected to two leads, we find that (i) for ΦAC = 0, the behavior of transmission zero at ΦAB = π is generic for the universal regime; (ii) for certain ΦAC and ΦAB, one can use the mesoscopic ring as spin filter even in the presence of the local interaction in the ring.
LEFT-HANDED METAMATERIALS MEASUREMENT UTILIZING PARALLEL-PLATE WAVEGUIDE SYSTEM
Authors: ZHU C. , LI L. , LIANG C. H. , SU Z. J. , CHEN X.
Published: June 2011

A novel measurement method of parallel-plate waveguide (PPW) system is introduced to detect the characteristics of left-handed metamaterials (LHMs). A sample of LHM composed of triangular open-loop resonator plus wire structures is proposed and measured by using this PPW system. The measurement results are in good agreement with the simulation results. Furthermore, the parametric retrieval algorithm, the calculated negative phase shift and the simulated subwavelength imaging result are given to validate the authenticity of PPW measurement system, which effectively demonstrates the measured transmission passband is indeed a left-handed passband.
INFLUENCE OF SILICON ADDITION ON SEEBECK COEFFICIENT OF MnSi1.7 FILMS
Authors: HOU Q. R. , GU B. F. , CHEN Y. B. , HE Y. J.
Published: June 2011

MnSi 1.7 films with different thicknesses (16–242 nm) are prepared by magnetron sputtering and electron beam evaporation. When the MnSi 1.7 film thickness is about 40 nm or above, MnSi 1.7 films are p-type in the whole temperature range (300–700 K) in agreement with reports in literature. By co-sputtering of MnSi 1.85 and silicon targets or deposition of Si / Mn multi-layers with a larger thickness ratio, silicon is added to the films and the Seebeck coefficients transform from positive to negative with increasing temperature. The Seebeck coefficients at room temperature and 633 K are +0.098 mV/K and -0.358 mV/K, respectively. By reducing the MnSi 1.7 film thickness to 27 nm, the transition of Seebeck coefficient from positive to negative is also observed although silicon is not added intentionally. When an ultra-thin aluminum layer is deposited between MnSi x(x < 1.7) and Si layers to enhance silicon diffusion, the p- to n-type transition temperature decreases about 100 K. The silicon-added MnSi 1.7 films usually have higher electrical resistivity.
CALL WARRANTS IN CHINA'S SECURITIES MARKET: PRICING BIASES AND INVESTORS' CONFUSION
Authors: FAN WEI , YUAN XINYI
Published: June 2011

This paper examines the price performance of call warrants in China's securities market. A recent sample of daily call warrant prices observed during the period from August 2005 to March 2007 is used. To the best of our knowledge this is the only recent study to using data from China and as such it greatly enhances our understanding of this particular market. On average, we find that the observed market prices are irrationally higher than the Black-Scholes model prices by 80.38% (using 180-day historical volatility) and 140.50% (using EGARCH volatility). However, we find another anomalous phenomenon that some of the call warrants prices are not only lower than the model prices, but have also recently been anomalously under their lower bounds. This finding seems to violate the "no arbitrage" principle. Among the convincing reasons, our findings indicate that trading mechanism constraints in China's securities market prevent rational investors from driving the prices of these call warrants to a reasonable level. Arbitrage chances are found to exist in some specific cases when the call warrant prices are below their lower bounds.
The Vicious Circle of Perceived Stigmatization, Depressiveness, Anxiety, and Low Quality of Life in Substituted Heroin Addicts
Authors: Frischknecht Ulrich , Beckmann Bettina , Heinrich Milena , Kniest Anja , Nakovics Helmut , Kiefer Falk , Mann Karl , Hermann Derik
Published: June 2011

Background: Perceived stigmatization of drug addicts may interact with negative mood states and thus may contribute to the maintenance of addictive behavior. Methods: Opiate maintenance patients (n = 106) and an unselected comparison group (n = 144) rated self-report questionnaires about perceived stigmatization, quality of life (QoL), depressiveness, anxiety, self-esteem, addiction characteristics, and social support. Results: 63% of opiate maintenance patients felt discriminated in contrast to 16% of the comparison group. Perceived stigmatization was rated higher by opiate maintenance patients, and all domains of QoL were rated lower, even when statistically controlling depressiveness, anxiety and social factors. Perceived stigmatization was correlated to depressiveness, anxiety, low self-esteem and low QoL, but not addiction characteristics and social support. Structural equation models revealed anxiety and the pathway depressiveness enhancing feelings of being stigmatized resulting in low self-esteem to explain 74% of variance in mental QoL, whereas anxiety and a pathway stigmatization inducing depressiveness leading to low self-esteem explained 49% of variance in physical QoL. Conclusions: A vicious circle of stigmatization, negative affective states and low QoL was confirmed. In addition to societal antistigma campaigns, antidepressive and anxiolytic therapy might have the potential to diminish feelings of being stigmatized and to improve QoL.