bluuebunny/crossref_metadata_2025 huggingface dataset:
A novel animal model to study non‐spontaneous bisphosphonates osteonecrosis of jaw
Authors: Biasotto Matteo , Chiandussi Silvia , Zacchigna Serena , Moimas Silvia , Dore Franca , Pozzato Gabriele , Cavalli Fabio , Zanconati Fabrizio , Contardo Luca , Giacca Mauro , Di Lenarda Roberto
Published: March 2010

J Oral Pathol Med (2010) 39: 390–396

The aim of this study was to evaluate a novel animal model of bisphosphonates‐associated osteonecrosis, which realistically recapitulates the same pathological human condition. Five Wistar rats were given intravenous zoledronic acid 0.04 mg once a week for 5 weeks. After 2 weeks, the animals underwent the extraction of an upper molar, producing a 4 mm‐diameter bone defect on the same site. After 7 weeks from the extraction, the animals were clinically examined and a bone scintigraphy was carried out. After an additional week, the rats were killed and both Computerized Tomography and histological analysis were performed. Five rats, not treated with zoledronic acid and exposed to the same surgical treatment, were used as controls. At 7 weeks after the extraction, all the rats treated with zoledronic acid showed expansion of the defect and bone exposure. These features were confirmed by bone scintigraphy. The rats of the control group demonstrated epithelialization of the bone defect and a normal uptake of the contrast medium during the scan. The Computerized Tomography scan disclosed irregularity of the cortical margin and bone destruction, which were not evident in the control group. On microscopy, the samples showed necrotic bone, loss of osteocytes and peripheral resorption without inflammatory infiltrate, while the controls showed normal bone healing. The rat treated with zoledronic acid can be considered a novel, reliable and reproducible animal model to understand better the pathophysiology of osteonecrosis of the jaw and to develop a therapeutic approach.
Interferon‐γ Inhibits Metalloproteinase Activity and Cytotrophoblast Cell Migration
Authors: Fontana Vanina Andrea , Sanchez Melisa , Cebral Elisa , Calvo Juan Carlos
Published: March 2010

Citation Fontana VA, Sanchez M, Cebral E, Calvo JC. Interferon‐γ inhibits metalloproteinase activity and cytotrophoblast cell migration. Am J Reprod Immunol 2010; 64: 20–26

Problem  Establishment of a successful pregnancy relies on a complex fetal–mother communication that starts with the embryo adhering and invading the endometrium. This requires remodeling of extracellular matrix, performed by metalloproteinases. Cytokines, such as interferon‐γ (IFN‐γ), play a role in implantation and could affect the success of pregnancy.

Method of study  Using JEG‐3 cell line as model, we cultured the cells in the presence or absence of IFN‐γ and determined the activities of MMP‐2 and MMP‐9 using zymography and the secretion of leptin using Western blot.

Results  Interferon‐γ inhibits gelatinase activity from MMP‐2 and MMP‐9 in a dose‐dependent manner, reducing the secretion of leptin (not because of a general inhibition on protein synthesis) and impairs cell migration on Matrigel.

Conclusion  Our results correlate with previous reports from our laboratory indicating that IFN‐ γ is deleterious for mouse embryo outgrowth, having an effect on metalloproteinases activity as well as leptin secretion.
The competitor‐introduced Gγ recruitment system, a new approach for screening affinity‐enhanced proteins
Authors: Fukuda Nobuo , Ishii Jun , Tanaka Tsutomu , Kondo Akihiko
Published: March 2010

We have developed a new approach based on the Gγ recruitment system to screen affinity‐enhanced proteins by expressing a binding competitor. The previously established Gγ recruitment system is a yeast two‐hybrid (Y2H) system that utilizes G‐protein signaling, and is based on the fact that membrane localization of the G‐protein γ subunit (Gγ) is essential for signal transduction in yeast. In the original Y2H system, an engineered Gγ that lacks membrane localization upon deletion of the lipid modification site (Gγcyto) is produced, and a candidate protein with an artificial lipidation site and its counterpart fused with Gγcyto are expressed. As protein–protein interactions bring Gγcyto towards the plasma membrane, G‐protein signaling can be activated, and the interaction is detected by various cellular responses as the readout. In the current study, we expressed a third cytosolic protein that competes with the candidate protein to specifically isolate affinity‐enhanced mutants from a mutation library of the candidate protein. Enhancing the affinity of the protein candidate guides the counterpart–Gγcyto fusion protein towards the plasma membrane and activates signaling. Using mutants of the Z domain derived from Staphylococcus aureus protein A as candidate proteins or competitors, and the Fc portion of human immunoglobulin G (IgG) as the counterpart, we demonstrate that affinity‐enhanced proteins can be effectively screened from a library containing a 10 000‐fold excess of non‐enhanced proteins. This new approach, called the competitor‐introduced Gγ recruitment system, will be useful for efficient discovery of rare valuable candidates hidden among excess ordinary ones.

Structured digital abstract

MINT‐7556266: Fc portion of human IgG (uniprotkb:P01857) physically interacts (MI:0915) with Z domain of protein A (uniprotkb:P38507) by two hybrid (MI:0018)
The bactericidal action on Escherichia coli of ZF‐RNase‐3 is triggered by the suicidal action of the bacterium OmpT protease
Authors: Zanfardino Anna , Pizzo Elio , Di Maro Antimo , Varcamonti Mario , D’Alessio Giuseppe
Published: March 2010

ZF‐RNase‐3 is one of the RNases from zebrafish (Danio rerio) with special (i.e. noncatalytic) properties. These include angiogenic and bactericidal activities. Given the interest of fish RNases as host‐defense effectors, we studied the mechanism of the bactericidal action of ZF‐RNase‐3 on Escherichia coli as a model Gram‐negative bacterium. The results obtained indicate that the bactericidal activity of ZF‐RNase‐3 is not lost when its catalytic RNase activity is obliterated. On the other hand, fully denatured ZF‐RNase‐3 conserves its bactericidal activity. When ZF‐RNase‐3 is added to E. coli cultures, it is cleaved at a specific Arg‐Arg peptide bond, thus engendering two peptide fragments. The larger fragment (residues 31–124), produced by proteolysis and reduction of a disulfide, is recognized as the actual bactericidal agent. The protease responsible for the proteolytic attack has been identified with OmpT, an outer membrane E. coli omptin protease. However, the most remarkable result obtained in the present study is the finding that the microbicidal action of ZF‐RNase‐3 can be achieved only with the suicidal cooperation of the bacterium itself.
Immunotherapy of melanoma
Authors: HERSEY Peter
Published: March 2010

A number of studies have shown that melanoma is a particularly immunogenic tumour, at least in the early stages of its development. A range of clinical phenomena also suggests that immune responses play an important role in the natural history of the disease, including the total or partial regression of primary melanomas associated with lymphoid infiltrates. Immunization with a variety of vaccines can increase immune responses to melanoma, but whether this is of therapeutic benefit remains unclear. Various trials of melanoma vaccines have shown benefits but their significance has been marginal to date. Two trials have actually shown an adverse effect on survival. Stimulation of immune responses by blocking down‐regulatory mechanisms in the immune system has evolved as a potential therapeutic approach following studies that have shown that immune responses are finely regulated by a series of receptors and ligands on lymphocytes and antigen presenting cells. The best studied of these approaches is the blockade of the cytotoxic T‐lymphocyte antigen 4 receptor on T cells, which allows the generation of more effector cells for longer periods. Agents targeting this receptor have shown promising results and continue to be studied.
Insights into piezophily from genetic studies on the deep‐sea bacterium, Photobacterium profundum SS9
Authors: El‐Hajj Ziad W. , Allcock David , Tryfona Theodora , Lauro Federico M. , Sawyer Lindsay , Bartlett Douglas H. , Ferguson Gail P.
Published: March 2010

The deep‐sea bacterium, Photobacterium profundum SS9, has been adopted as a model organism to understand the molecular basis of cold‐adapted high‐pressure‐loving (piezophilic) growth. Despite growing optimally at 28 MPa (15° C), P. profundum SS9 can grow over a wide range of pressures and temperatures. The ability to grow at atmospheric pressure has enabled a limited set of genetic tools to be developed, which has provided genetic insights into the mechanism of piezophilic growth in P. profundum SS9. This review focuses on how genetic studies have uncovered the importance of processes affecting the DNA and the bacterial cell envelope in the piezophilic growth of P. profundum SS9. In addition, a method was developed to assess quantitative piezophilic colony growth of P. profundum SS9 on solid agar. Future studies, using this methodology, could provide novel insights into the molecular basis of piezophilic, surface‐attached growth.
Pressure‐induced phase transitions in triacylglycerides
Authors: Ferstl Peter , Gillig Sebastian , Kaufmann Christoph , Dürr Christoph , Eder Cornelia , Wierschem Andreas , Ruß Winfried
Published: March 2010

The melting point of triacylglycerides (TAGs) under atmospheric pressure depends on both the fatty acid composition and crystalline structure of the polymorphic state, which are influenced by the temperature treatment history of the TAG. In this contribution, the additional effect of high hydrostatic pressure is described. Samples were placed in a temperature‐controlled cell and pressurized up to 450 MPa. The phase transition was investigated either by perpendicular light scattering and transmission or with a polarized‐light microscope. The high‐pressure polarized‐light microscope allows a precise determination of the melting point. The investigated TAGs showed a significant nonlinear increase of the melting point with pressure. Light scattering and transmission were used to observe the phase change in the high‐pressure cell. Similar to supercooling in temperature‐induced phase transition, we found a dramatic increase of the delay time in our pressure‐induced solidification. Even the dependency of this induction time on the control parameter pressure was similar to that in temperature‐driven crystallization. We propose that different crystalline structures may be obtained by superpressuring instead of supercooling.
Proteins involved in Campylobacter jejuni 81–176 recovery after high‐pressure treatment
Authors: Bièche Clémence , de Lamballerie Marie , Federighi Michel , Le Bail Alain , Tresse Odile
Published: March 2010

Campylobacteriosis has been recognized as the major bacterial food‐borne infection worldwide. Campylobacter, especially C. jejuni, contaminate mainly poultry meat. Although more sensitive than other food‐borne pathogens to many stresses, C. jejuni can survive food processing and go on to reach its final reservoir (the human gut). Genomic analyses of this organism indicate a lack of genes described in other gram‐negative bacteria to overcome stresses. The high‐pressure recovery response of C. jejuni 81–176 was analyzed from two‐dimensional electrophoretic profiles of the cytoplasmic proteome. The main cellular mechanisms controlling the down‐ and upregulated proteins are discussed.
High‐pressure adaptation of muscle proteins from deep‐sea fishes, Coryphaenoides yaquinae and C. armatus
Authors: Morita Takami
Published: March 2010

The evolutionary adaptations of functional genes to life at high pressures are not well understood. To elucidate the mechanisms of protein adaptation to high pressures, we isolated two muscle protein‐encoding cDNAs, α‐actin and myosin heavy chain (MyHC), derived from skeletal muscles of two deep‐sea fishes, Coryphaenoides yaquinae and C. armatus, and two non‐deep‐sea fishes, C. acrolepis and C. cinereus. The α‐actins from two deep‐sea fishes have three amino acid substitutions in comparison to those of non‐deep‐sea fishes. These substitutions enable the deep‐sea fish actins to function even at 60 MPa. The MyHCs of the two deep‐sea fishes have a proline residue in the loop‐1 region and have a shorter loop‐2 region than the non‐deep‐sea fishes. Additionally, the MyHCs of deep‐sea fishes have biased amino acid substitutions at core positions within the coiled‐coil structure of the rod region. The roles of these substitutions in the deep‐sea fishes MyHCs, however, remain unclear.
High hydrostatic pressure and the cell membrane
Authors: Bravim Fernanda , de Freitas Jéssica M. , Fernandes A. Alberto R. , Fernandes Patricia M. B.
Published: March 2010

The brewing and baking yeast Saccharomyces cerevisiae is a useful eukaryotic model of stress response systems whose study could lead to the understanding of stress response mechanisms in other organisms. High hydrostatic pressure (HHP) exerts broad effects upon yeast cells, interfering with cell membranes, cellular architecture, and the processes of polymerization and denaturation of proteins. In this review, we focus on the effect of HHP on the S. cerevisiae cell membrane and describe the main signaling pathways involved in the pressure response.
Pressure study on symmetric and asymmetric phospholipid bilayers: effect of vesicle size on Prodan fluorescence
Authors: Goto Masaki , Kusube Masataka , Nishimoto Makoto , Tamai Nobutake , Matsuki Hitoshi , Kaneshina Shoji
Published: March 2010

The bilayer phase behavior of symmetric and asymmetric phosphatidylcholines (PCs), 1,2‐diheptadecanoyl‐PC (C17PC), 1‐palmitoyl‐2‐stearoyl‐PC (PSPC), and 1‐stearoyl‐2‐palmitoyl‐PC (SPPC), with different vesicle sizes were investigated by a high‐pressure fluorescence method using the polarity‐sensitive fluorescent probe Prodan. The second derivative of fluorescence spectra for all the PCs of small‐sized vesicle showed four minima characteristic of four membrane states on the spectra irrespective of the acyl‐chain symmetry, whereas those of large‐sized vesicle had one more minimum originating from the most hydrophilic site at the membrane surface. These findings indicate that Prodan molecules can distribute into multiple sites in the bilayer and move around the head‐group region depending on the vesicle size. The behavior of the spectra in the SPPC bilayer suggested that the interdigitated gel phase had a less polar “pocket” formed by a space between uneven terminal methyl ends of the sn‐1 and sn‐2 chains. It turned out that the curvature of vesicles affects the distribution of the Prodan molecules in all phases, more particularly in the interdigitated gel phase.
Pressure effect on the bilayer phase transition of asymmetric lipids with an unsaturated acyl chain
Authors: Tada Kaori , Goto Masaki , Tamai Nobutake , Matsuki Hitoshi , Kaneshina Shoji
Published: March 2010

The bilayer phase transitions of mixed‐chain lipids with monounsaturated acyl chain in the sn‐2 position, 1‐myristoyl‐2‐oleoyl‐sn‐glycero‐3‐phosphocholine (MOPC), 1‐palmitoyl‐2‐oleoyl‐sn‐glycero‐3‐phosphocholine (POPC), and 1‐stearoyl‐2‐oleoyl‐sn‐glycero‐3‐phosphocholine (SOPC), and with a polyunsaturated acyl chain in the sn‐2 position, 1‐stearoyl‐2‐linoleoyl‐sn‐glycero‐3‐phosphocholine (SLPC), 1‐stearoyl‐2‐arachidonoyl‐sn‐glycero‐3‐phosphocholine (SAPC), and 1‐stearoyl‐2‐docosahexaenoyl‐sn‐glycero‐3‐phosphocholine (SDPC), were observed by differential scanning calorimetry (DSC) under ambient pressure and by light‐transmittance measurements under high pressure. The DSC thermogram for each lipid bilayer showed only one transition between the lamellar gel and liquid crystalline phases. The introduction of one or two cis double bonds into the sn‐2 acyl chain caused the significant depression of the main‐transition temperature and an obvious decrease of enthalpy and volume changes associated with the transition. These features are attributable to loose packing of saturated and unsaturated acyl chains in the bilayer gel phase. The existence of four or six double bonds in the sn‐2 chain produced no further decrease in the transition temperature, and in fact six double bonds caused a slight increase in the transition temperature. Thermodynamic properties associated with the bilayer phase transition were discussed.
Effects of compressed unsaturated hydrocarbon gases on yeast growth
Authors: Kawachi Satoshi , Arao Toshiaki , Suzuki Yoshihisa , Tamura Katsuhiro
Published: March 2010

The effect of compressed unsaturated hydrocarbon gases on the growth of the yeast Saccharomyces cerevisiae was investigated by microcalorimetry. The growth thermograms showed that unsaturated hydrocarbon gases inhibited yeast growth. As an approach to determining the comparative toxicity of unsaturated hydrocarbon gases, we determined the 50% inhibitory pressure (IP50) and the minimum inhibitory pressure (MIP). On the basis of the IP50 and MIP values, the inhibitory potency of the gases increased in the order ethylene < propylene < 1‐butene. Additionally, scanning electron microscopy showed that cells treated with unsaturated hydrocarbon gases were damaged, including invagination of the cell surface.
Le système de retraite de la fonction publique à Taïwan: problèmes d'équité au sein du système et entre les différents régimes
Authors: Shao Ai Ju
Published: March 2010

Cet article examine les défis que doit relever le nouveau fonds de pensions de la fonction publique (NSPFS) de Taïwan, Chine. En vigueur depuis moins de vingt ans, ce jeune système est confrontéà des déséquilibres financiers et fait l'objet de controverses en raison de la générosité des prestations qu'il offre. Le présent article présente pour commencer les différents systèmes de retraite en vigueur à Taïwan, en particulier le système qui couvre les salariés de l'administration publique générale. Il analyse ensuite les difficultés financières auxquelles est confronté le régime des salariés de l'administration générale, notamment la hausse du coût des prestations pour l'ensemble des contribuables. Enfin, il développe les orientations qui pourraient être suivies pour réformer le système de retraite de la fonction publique, notamment la baisse des prestations, le durcissement des conditions d'ouverture des droits et la création d'un nouveau système. En ce qui concerne cette dernière proposition, tout nouveau système susceptible d'être envisagé doit garantir la viabilité financière à plus long terme du régime tout en offrant une équité optimale pour toutes les parties prenantes, y compris les contribuables.
El sistema público de pensiones en Taiwán: problemas de igualdad en los sistemas y entre los sistemas
Authors: Shao Ai Ju
Published: March 2010

En este artículo se analizan los desafíos que afronta el Nuevo Sistema del Fondo de Pensiones de la Función Pública en Taiwán, China. Menos de dos décadas después de su puesta en marcha, este nuevo sistema afronta desajustes financieros y es objeto de polémica por la generosidad de las disposiciones que regulan sus prestaciones. En primer lugar, el artículo presenta los diferentes sistemas de seguridad en la vejez existentes en Taiwán y se centra en los trabajadores de la función pública en general. A continuación, el artículo examina los desafíos financieros que afronta el sistema general de pensiones del sector público, incluido el aumento del coste de sus prestaciones para todos los contribuyentes. Por último, el artículo propone una serie de posibles orientaciones que el sistema general del sector público debería considerar al acometer las reformas, entre otras, la reducción del importe de las prestaciones, criterios más restrictivos de elegibilidad o el establecimiento de un nuevo sistema. En este último caso, toda propuesta de un nuevo sistema debe aspirar a realizar el objetivo de lograr solidez financiera a largo plazo y simultáneamente garantizar una ecuanimidad óptima entre todas las partes implicadas, incluidos los contribuyentes.
La atención médica como prestación de seguridad social: enfoques institucionales para la extensión de la cobertura
Authors: Ron Aviva
Published: March 2010

Para lograr una cobertura médica universal es necesaria una combinación adecuada de regímenes de seguro social contributivos obligatorios con mecanismos de inclusión de la población activa de la economía informal y una asistencia social de base impositiva para las personas sin ingresos suficientes para abonar sus propias cotizaciones. Este artículo aboga por una inversión de la tendencia a la separación del seguro social de enfermedad entre distintas instancias sanitarias e insta a extender la cobertura médica usando los regímenes de seguridad social del sector estructurado existentes debido a que cuentan con las estructuras institucionales y el respaldo político necesarios. El artículo repasa los motivos del lento ritmo de extensión de la cobertura hasta la fecha, recalca el valor añadido de la incorporación de la atención médica como prestación de la seguridad social y reconoce la importancia de mantener los vínculos entre los regímenes reglamentarios de seguro de enfermedad y los regímenes comunitarios de seguro o microseguro de enfermedad bien reglamentados.
Exploiting formalin‐preserved fish specimens for resources of DNA barcoding
Authors: ZHANG J.
Published: March 2010

With the development of the DNA barcoding project, a large number of specimens are required to establish the library of reference barcode. Formalin‐fixed samples from museums provide a potential resource for it. However, recovery of DNA and amplification of the target gene from formalin‐fixed samples are challenging. In this study, a hot alkali pre‐treatment accompanied by the use of cetyltrimethylammonium bromide (CTAB) method was employed for DNA recovery from formalin‐preserved samples, with the purpose of pursuing the optimal condition for high quantity and quality of DNA and minimizing PCR inhibition. Meanwhile, a semi‐nested PCR‐based method was developed to enhance the efficacy of amplification. This advanced protocol was demonstrated to be reliable and effective. Even for 23‐year‐old samples, genomic DNA could be extracted, and COI gene was correctly sequenced.
Review of electrical characterization of ultra-shallow junctions with micro four-point probes
Authors: Petersen Dirch H. , Hansen Ole , Hansen Torben M. , Bøggild Peter , Lin Rong , Kjær Daniel , Nielsen Peter F. , Clarysse Trudo , Vandervorst Wilfried , Rosseel Erik , Bennett Nick S. , Cowern Nick E. B.
Published: March 2010

Electrical characterization of ultra-shallow junctions, relying on advanced implant and anneal processes, has received much attention in the past few years since conventional characterization methods fail. With continued scaling of semiconductor devices, the problems associated with conventional techniques will become even more evident. In several recent studies micro four-point probe (M4PP) has been demonstrated as a reliable high precision metrology method for both sheet resistance and Hall effect measurements of ultra-shallow implants and has revealed a promising potential for carrier profiling.
Simulation of p-n junctions: Present and future challenges for technologies beyond 32 nm
Authors: Pelaz Lourdes , Marqués Luis A. , Aboy María , Santos Iván , López Pedro , Duffy Ray
Published: March 2010

Ion implantation continues being the dominant technique to introduce dopants in Si devices. With the device feature size in the nanometer scale, the accurate and detailed description of as-implanted dopant and damage profiles is becoming key as advanced annealing techniques are almost diffusionless. The demanding requirements for ultrashallow junction formation are stimulating the development of improved and detailed models for molecular implants and for the kinetics of amorphous damage. Additional challenges arise in the doping of advanced architectures, such as fin field effect transistors, because the introduction of highly tilted ions is quite inefficient and, in addition, the regrowth of amorphous regions in narrow structures is hampered by the slow regrowth at free interfaces and {111} planes. Atomistic simulations play a relevant role to provide the understanding for the development of simplified physically based models computationally more efficient.
Electrical characterization of InGaAs ultra-shallow junctions
Authors: Petersen Dirch H. , Hansen Ole , Bøggild Peter , Lin Rong , Nielsen Peter F. , Lin Dennis , Adelmann Christoph , Alian Alireza , Merckling Clement , Penaud Julien , Brammertz Guy , Goossens Jozefien , Vandervorst Wilfried , Clarysse Trudo
Published: March 2010

In this study, we investigate the limitations to sheet resistance and Hall effect characterization of ultra-shallow junctions (USJs) in In0.53Ga0.47As. We compare conventional van der Pauw and Hall effect measurements with micro four-point probe (M4PP) and micro Hall effect methods. Due to the high carrier mobility of InGaAs, we extend the micro-Hall effect position error suppression method to also take geometrical magnetoresistance into account. We find that the conventional techniques fail to measure accurately on n++∕p+ USJ due to a significant leakage current, whereas the M4PP and micro Hall effect methods are able to give accurate results. Finally, we observe a significant reduction in the carrier mobility for InGaAs USJ.
Photoreflectance characterization of ultrashallow junction activation in millisecond annealing
Authors: Chism Will , Current Michael , Vartanian Victor
Published: March 2010

Photoreflectance (PR) provides an optical means for rapid and precise measurement of near-surface electric fields in semiconductor materials. This article details the use of PR to characterize dopant activation in ultrashallow junction (USJ) structures formed using millisecond annealing processes. USJ structures were formed in silicon using 500eV B implantation with a dose of 1015∕cm2, followed by flash anneals at 1250–1350°C. Reference metrology was performed using secondary ion mass spectrometry and various sheet resistance (Rs) methods. Methods to calibrate PR signals to active carrier concentration in USJ structures, including halo-doped samples, are described. PR is shown to be highly sensitive to active dopant concentrations in USJ structures formed by millisecond annealing.
Shallow As dose measurements of patterned wafers with secondary ion mass spectrometry and low energy electron induced x-ray emission spectroscopy
Authors: Ehrke H.-U. , Loibl N. , Moret M. P. , Horréard F. , Choi J. , Hombourger C. , Paret V. , Benbalagh R. , Morel N. , Schuhmacher M.
Published: March 2010

Secondary ion mass spectrometry (SIMS) and low energy electron induced x-ray emission spectroscopy (LEXES) are both well established technologies. SIMS tools are the ultimate reference for depth profiling and direct measurement of dopants with highest sensitivity and dynamic range. The LEXES-based shallow probe is a versatile, sensitive, in-line metrology tool for thin layer elemental composition and dopant dosimetry in semiconductor production. In this contribution, the ability of LEXES and SIMS techniques to differentiate nominal dose differences among three different 300mm patterned wafers are compared. In each die, several test pads were available for dose measurements. Five neighboring dies were measured by LEXES and afterward by SIMS. The repeatability measurements of both techniques (<0.5%) is suitable to determine dose nonuniformity from die to die and to discriminate nominal dose between wafers as small as 3%.
Nondestructive extraction of junction depths of active doping profiles from photomodulated optical reflectance offset curves
Authors: Bogdanowicz Janusz , Dortu Fabian , Clarysse Trudo , Vandervorst Wilfried , Rosseel Erik , Nguyen Ngoc Duy , Shaughnessy Derrick , Salnik Alex , Nicolaides Lena
Published: March 2010

The ITRS Roadmap highlights the electrical characterization of the source and drain extension regions as a key challenge for future complimentary-metal-oxide-semiconductor technology. Presently, an accurate determination of the depth of ultrashallow junctions can routinely only be performed by time-consuming and destructive techniques such as secondary ion mass spectrometry (SIMS). In this work, the authors propose to use the fast and nondestructive photomodulated optical reflectance (PMOR) technique , as implemented in the Therma-Probe® (TP) dopant metrology system, for these purposes. PMOR is a pump-probe technique based on the measurement of the pump-induced modulated change in probe reflectance, i.e., the so-called (photo) modulated reflectance. In this article, the authors demonstrate that the absolute junction depths of boxlike active dopant structures can be extracted in a very simple and straightforward way from the TP offset curves, which represent the behavior of the modulated reflectance as a function of the pump-probe beam spacing. Although the procedure is based on the insights into the physical behavior of the offset curves, no modeling is involved in the actual extraction process itself. The extracted junction depths are in good correlation with the corresponding junction depths as measured by means of SIMS. The technique has a subnanometer depth sensitivity for depths ranging from 10to35nm with the present Therma-Probe® 630XP system. The extension of the proposed procedure to the general ultrashallow profiles is also explored and discussed.
Application of the Storing Matter technique to the analysis of semiconductor materials
Authors: Mansilla C. , Wirtz T.
Published: March 2010

Secondary-ion-mass spectrometry (SIMS) is a very powerful technique for surface and thin film characterization due to its high sensitivity and excellent depth resolution. However, it suffers from one major drawback that gives rise to very significant problems with quantification; the ionization yield of a given sputtered element may vary by several orders of magnitude depending on the composition of the matrix in which it is located (the so-called matrix effect). Storing Matter is a new analytical technique, which has been developed to avoid the SIMS matrix effect while keeping or even improving the excellent sensitivity of SIMS.
Photovoltage versus microprobe sheet resistance measurements on ultrashallow structures
Authors: Clarysse Trudo , Moussa Alain , Parmentier Brigitte , Bogdanowicz Janusz , Vandervorst Wilfried , Bender Hugo , Pfeffer Markus , Schellenberger Martin , Nielsen Peter F. , Thorsteinsson Sune , Lin Rong , Petersen Dirch
Published: March 2010

Earlier work [T. Clarysse et al., Mater. Sci. Eng., B 114–115, 166 (2004); T. Clarysse et al., Mater. Res. Soc. Symp. Proc. 912, 197 (2006)] has shown that only few contemporary tools are able to measure reliably (within the international technology roadmap for semiconductors specifications) sheet resistances on ultrashallow (sub-50-nm) chemical-vapor-deposited layers [T. Clarysse et al., Mater. Res. Soc. Symp. Proc. 912, 197 (2006)], especially in the presence of medium/highly doped underlying layers (representative for well/halo implants). Here the authors examine more closely the sheet resistance anomalies which have recently been observed between junction photovoltage (JPV) based tools and a micrometer-resolution four-point probe (M4PP) tool on a variety of difficult, state-of-the-art sub-32-nm complementary metal-oxide semiconductor structures (low energy and cluster implants, with/without halo, flash- and laser-based millisecond anneal). Conventional four-point probe tools fail on almost all of these samples due to excessive probe penetration, whereas in several cases variable probe spacing (using a conventional spreading resistance probe tool) [T. Clarysse et al., Mater. Sci. Eng. R. 47, 123 (2004)] still gives useful values to within about 20%–35% due to its limited probe penetration (5–10 nm at 5 g load). M4PP measurements give systematically a sensible and reproducible result. This is also the case for JPV-based sheet resistance measurements, although these appear to be prone to correct calibration procedures and are not designed for the characterization of multijunctions. Moreover, in a significant number of cases, residual damage and/or unexpected junction-leakage currents appear to induce a strong signal reduction, limiting the applicability of the JPV technique. This has been further investigated by transmission-electron microscopy, high carrier-injection photomodulated optical-reflectance, and Synopsis-Sentaurus device simulations.
Ultralow energy boron implants in silicon characterization by nonoxidizing secondary ion mass spectrometry analysis and soft x-ray grazing incidence x-ray fluorescence techniques
Authors: Giubertoni Damiano , Iacob Erica , Hoenicke P. , Beckhoff B. , Pepponi Giancarlo , Gennaro Salvatore , Bersani Massimo
Published: March 2010

Boron ultralow energy (0.2–3 keV) high dose (1×1015 cm−2) implants in single crystalline Si (100) were characterized by secondary ion mass spectrometry using an ultralow energy (0.35–0.5 keV) O2+ ion primary beam and collecting positive secondary ions. In particular, the not fully oxidizing approaches (primary beam oblique incidence and ultrahigh vacuum analysis atmosphere) were investigated because they are expected to provide better accuracy on the profile shape, especially in the region between the surface and the native oxide/substrate interface. The main drawback represented by an early formation of roughness on the crater bottom has been overcome by combining the ion sputtering with the rotation of the sample during the analysis. The reduced formation of roughness ensures more stable sputtering conditions and a more stable erosion rate with a more accurate depth calibration. The measured dose values were then cross-checked comparing them with results of soft x-ray synchrotron radiation grazing incidence x-ray fluorescence.
ON THE RIEMANN HYPOTHESIS, AREA QUANTIZATION, DIRAC OPERATORS, MODULARITY, AND RENORMALIZATION GROUP
Authors: CASTRO CARLOS
Published: March 2010

Two methods to prove the Riemann Hypothesis are presented. One is based on the modular properties of Θ (theta) functions and the other on the Hilbert–Polya proposal to find an operator whose spectrum reproduces the ordinates ρn (imaginary parts) of the zeta zeros in the critical line: sn = ½ + iρn. A detailed analysis of a one-dimensional Dirac-like operator with a potential V(x) is given that reproduces the spectrum of energy levels En = ρn, when the boundary conditions ΨE (x = -∞) = ± ΨE (x = +∞) are imposed. Such potential V(x) is derived implicitly from the relation [Formula: see text], where the functional form of [Formula: see text] is given by the full-fledged Riemann–von Mangoldt counting function of the zeta zeros, including the fluctuating as well as the [Formula: see text] terms. The construction is also extended to self-adjoint Schroedinger operators. Crucial is the introduction of an energy-dependent cut-off function Λ(E). Finally, the natural quantization of the phase space areas (associated to nonperiodic crystal-like structures) in integer multiples of π follows from the Bohr–Sommerfeld quantization conditions of Quantum Mechanics. It allows to find a physical reasoning why the average density of the primes distribution for very large [Formula: see text] has a one-to-one correspondence with the asymptotic limit of the inverse average density of the zeta zeros in the critical line suggesting intriguing connections to the renormalization group program.
FRACTIONAL QUANTUM HALL STATES IN GRAPHENE
Authors: JELLAL AHMED , MALIKA BELLATI
Published: March 2010

We quantum mechanically analyze the fractional quantum Hall effect in graphene. This will be done by building the corresponding states in terms of a potential governing the interactions and discussing other issues. More precisely, we consider a system of particles in the presence of an external magnetic field and take into account of a specific interaction that captures the basic features of the Laughlin series [Formula: see text]. We show that how its Laughlin potential can be generalized to deal with the composite fermions in graphene. To give a concrete example, we consider the SU(N) wavefunctions and give a realization of the composite fermion filling factor. All these results will be obtained by generalizing the mapping between the Pauli–Schrödinger and Dirac Hamiltonian's to the interacting particle case. Meantime by making use of a gauge transformation, we establish a relation between the free and interacting Dirac operators. This shows that the involved interaction can actually be generated from a singular gauge transformation.
HAMILTONIAN FORMALISM FOR THE HIGHER KdV FLOWS ON THE SPACE OF CLOSED COMPLEX EQUICENTROAFFINE CURVES
Authors: FUJIOKA ATSUSHI , KUROSE TAKASHI
Published: March 2010

We study the higher KdV flows on the space of closed complex equicentroaffine curves as Hamiltonian systems. Using a suitable presymplectic structure of the space, we give the Hamiltonian flows associated with the higher KdV equations and a map between the space and the space of closed curves in the complex plane, which induces the Miura transformation between the higher KdV equations and the higher mKdV equations.
Post-glacial rebound of Iceland during the Holocene
Authors: Le Breton E. , Dauteuil O. , Biessy G.
Published: March 2010

The geodynamic context of Iceland provides the rare opportunity to analyse the combined effects of a ridge and a hotspot on deformation processes. From a digital elevation model, field analysis and a compilation of previous work, we propose a synthesis of vertical motions of Iceland during the Holocene with a focus on the post-glacial rebound. We determined two ancient marine limits, one above and one below the present sea level, estimated at 10 ka ± 300 years and 8150 ± 350 years bp, respectively. We calculated an uplift phase of 40–170 m with a rate of 2.1–9.2 cm a
−1
between 10 ka ± 300 years and 8150 ± 350 years bp, corresponding to the post-glacial rebound of Iceland following the Weichselian glaciation. Spatial variations of the rebound are mainly related to the local glacial dynamics (ice load and deglaciation history) rather than the geodynamic context. However, the relaxation time deduced from uplift data is 4167 years in west Iceland and 2000 years in SSW Iceland. We estimated viscosity from relaxation time, ranging from 2.1 × 10
19
Pa s to 3.2 × 10
19
Pa s. The significant difference in the relaxation time is due to local variation of the lithospheric thickness as a result of rifting rather than because of a variation of the viscosity.
Palaeocene–early Eocene inversion of the Phuquoc–Kampot Som Basin: SE Asian deformation associated with the suturing of Luconia
Authors: Fyhn Michael B.W. , Pedersen Stig A.S. , Boldreel Lars O. , Nielsen Lars H. , Green Paul F. , Dien Phan T. , Huyen Luong T. , Frei Dirk
Published: March 2010

The little explored Cambodian and Vietnamese Phuquoc–Kampot Som Basin is a Late Jurassic to Early Cretaceous foreland basin developed in response to the build-up of a palaeo-Pacific magmatic arc. A combination of seismic data, well data and outcrop geology complemented by fission track and U/Pb analysis is used to unravel the basin history. This reveals a hitherto unknown earliest Palaeogene basin inversion associated with the Luconian suturing to SE Asia and the shutdown of palaeo-Pacific subduction underneath SE Asia. The Phuquoc–Kampot Som Basin and the Khorat Basin in Thailand constitute the erosional remnants of a larger basin that covered large parts of SE Asia in Late Mesozoic time, and subsequently became segregated during earliest Palaeogene inversion and erosion. Inversion was focused along the several hundred kilometres long Kampot and Khmer–Chanthaburi fold belts that confine the Phuquoc–Kampot Som Basin and merge with the Mae Ping and the Three Pagodas fault zones. These connections, together with local NW–SE-trending sinistral transpressional faults offshore, indicate a link between initial SE Asian left-lateral strike-slip faulting and the Luconian suturing. The separation between the once unbroken Khmer–Chanthaburi Fold Belt and the Phetchabun Fold Belt in Thailand suggests a 50–100 km Cenozoic left-lateral offset across the Mae Ping Fault Zone.
No need for lithospheric extension for exhuming (U)HP rocks by normal faulting
Authors: Ring Uwe , Glodny Johannes
Published: March 2010

Extensional deformation is commonly considered most important for exhuming rocks from great depths. However, the necessary space for extending the lithosphere is usually lacking. We show that significant exhumation of (U)HP rocks occurs in extrusion wedges, which have a normal fault at their top and a thrust fault at their base. The normal fault at the top of an extrusion wedge is a geometric effect and does not result from lithospheric extension. Therefore, the exhumation of (U)HP rocks in extrusion wedges allows substantial exhumation beneath a normal fault during horizontal shortening and does not cause lithospheric attenuation.
Tectonic significance of present-day stress relief phenomena in formerly glaciated regions
Authors: Pascal Christophe , Roberts David , Gabrielsen Roy H.
Published: March 2010

Investigations were conducted in several regions of Norway with the purpose of detecting and measuring stress-relief features and to derive from them valuable information on the shallow-crustal stress state. Stress-relief features are induced by blasting and sudden rock unloading in road construction and quarrying operations, and are common in Norway and probably in other regions of Fennoscandia, as they are in NE America. Stress relief at the Earth's surface is diagnostic of anomalously high stress levels at shallow depths in the crust and characterizes the formerly glaciated Baltic and Canadian Precambrian shields. The mean orientation of the maximum horizontal compressive stress axis, as deduced from the orientation of stress-relief features, was found to be NW–SE, consistent with North Atlantic ridge-push forces. We show that our determined stress orientations are in excellent agreement with other kinds of stress data. As a final step, we estimate ridge-push force magnitudes from gravity data in the North Atlantic region. Our computations suggest that strong ridge-push forces characterize the Baltic and Canadian shields. We conclude from this quantitative analysis and our fieldwork results that present-day stress relief, in Fennoscandia and NE America, is mostly triggered by plate-scale ridge-push forces and not by residual glacial loading stresses.
Necrotizing Lymphocytic Vasculitis Limited to the Peripheral Nerves: Report of Six Cases and Review
Authors: Restrepo José Félix , Rondón Federico , Matteson Eric L. , Colegial Carlos H. , Quintana Gerardo , Iglesias-Gamarra Antonio
Published: March 2010

Background. The systemic vasculitides are syndromes characterized by inflammation and injury (necrosis or thrombosis) of blood vessels, resulting in clinical manifestations according to the affected vascular bed, but not classically in stocking-glove neuropathy.Objective. To describe a form of primary vasculitis affecting strictly peripheral nerves manifesting as stocking-glove neuropathy.Methods. Case series of 110 patients seen in three centers in Bogotá who presented with symptoms and signs of polyneuropathy and/or were identified with vasculitis affecting only the peripheral nerves, and who underwent sural nerve biopsy.Results. Six patients had a vasculitis affecting only the peripheral nerves diagnosed on sural nerve biopsy which demonstrated a mixed infiltrate of monocytes/macrophages and lymphocytes especially in the small epineurial blood vessels. Over time, all had worsening of symptoms, with grip weakness and motor deficits in the hand and feet. Serologies and acute phase reactants were normal in all patients. Treatment response to immunosuppression was satisfactory in 5 patients; 1 patient had progressive neurologic damage.Conclusions. There is a distinct form of primary vasculitis of the peripheral nervous system characterized by distal sensory polyneuropathy with stocking-glove distribution with good prognosis, few and minor relapses and good response to treatment even after delayed diagnosis.
Existence and Uniqueness of Solutions for theCauchy‐TypeProblems of Fractional Differential Equations
Authors: Kou Chunhai , Liu Jian , Ye Yan
Published: March 2010

By using the Banach fixed point theorem and step method, we study the existence and uniqueness of solutions for the Cauchy‐type problems of fractional differential equations. Meanwhile, by citing some counterexamples, it is pointed out that there exist a few defects in the proofs of the known results.
Flexible Interconnection Network for Dynamically and Partially Reconfigurable Architectures
Authors: Devaux Ludovic , Ben Sassi Sana , Pillement Sebastien , Chillet Daniel , Demigny Didier
Published: March 2010

The dynamic and partial reconfiguration of FPGAs enables the dynamic placement in reconfigurable zones of the tasks that describe an application. However, the dynamic management of the tasks impacts the communications since tasks are not present in the FPGA during all computation time. So, the task manager should ensure the allocation of each new task and their interconnection which is performed by a flexible interconnection network. In this article, various communication architectures, in particular interconnection networks, are studied. Each architecture is evaluated with respect to its suitability for the paradigm of the dynamic and partial reconfiguration in FPGA implementations. This study leads us to propose the DRAFT network that supports the communication constraints into the context of dynamic reconfiguration. We also present DRAGOON, the automatic generator of networks, which allows to implement and to simulate the DRAFT topology. Finally, DRAFT and the two most popular Networks-on-Chip are implemented in several configurations using DRAGOON, and compared considering real implementation results.
Male Remating Success and the Frequency of Copulatory Plugs in the Green Lynx SpiderPeucetia viridans(Araneae, Oxyopidae)
Authors: Ramirez Martin G. , Achekian Angelik C. , Coverley Catherine R. , Pierce Rachel M. , Eiman Sarah S. , Wetkowski Melissa M.
Published: March 2010

Peucetia viridansmales were allowed to mate with three virgin females and most matings resulted in live spiderlings, even when males lacked palpal paracymbial processes. Among females, the presence of copulatory plugs was inconsistent, and when present, their condition was not uniform; broken-off male paracymbia were often found in epigynal orifices. There was no size effect in a male's ability to completely plug a female's genital orifices, as well as no significant change in the pattern of plug production over consecutive mating trials. Among mated, field-collected females, the presence of plugs and paracymbia was variable, with females from some sites possessing neither structure. Field-collected females with no plugs were in significantly better condition than those with two plugs and in nearly significantly better condition than those with two paracymbia. Females in the best condition may excel at resisting the emplacement of genital obstructions and/or voiding such structures, potentially enabling them to mate with multiple males. Enhanced prey access mediated by increased water availability may be why females at two sites were in relatively better condition. If plugs help prevent sperm desiccation in inseminated females, this may have contributed to the absence of plugs from females at these two moister sites.