bluuebunny/crossref_metadata_2025 huggingface dataset:
Aeolian dust in the Talos Dome ice core (East Antarctica, Pacific/Ross Sea sector): Victoria Land versus remote sources over the last two climate cycles
Authors: Delmonte Barbara , Baroni Carlo , Andersson Per S. , Schoberg Hans , Hansson Margareta , Aciego Sarah , Petit Jean‐Robert , Albani Samuel , Mazzola Claudia , Maggi Valter , Frezzotti Massimo
Published: November 2010

A new ice core (TALDICE) drilled at Talos Dome (East Antarctica, Ross Sea sector) preserves a ca. 250 ka long record of palaeoclimate and atmospheric history. We investigate dust variability and provenance at the site during glacial periods and the Holocene through the Sr–Nd isotopic composition of ice core dust and potential source areas (PSA). We provide new isotopic data on dust sources from Victoria Land such as regoliths, glacial drifts, aeolian sands and beach deposits. Some of these sources are located at high altitude and are known to have been ice free throughout the Pleistocene. The major features of the TALDICE dust record are very similar to those from central East Antarctica. During glacial times, South America was the dominant dust supplier for Talos Dome as well as for the entire East Antarctic plateau. Conversely, during the Holocene the principal input of mineral dust at Talos Dome probably derives from proximal sources which are the ice‐free areas of northern Victoria Land, located at similar altitude with respect to the drilling site. Atmospheric mobilisation of dust from these neighbouring areas and transport inland to Talos Dome can be ultimately associated with advection of maritime air masses from the Pacific/Ross Sea region. Copyright © 2010 John Wiley & Sons, Ltd.
Amorphous, nanocrystalline and crystalline calcium carbonates in biological materials
Authors: Wehrmeister U. , Jacob D. E. , Soldati A. L. , Loges N. , Häger T. , Hofmeister W.
Published: November 2010

Raman spectroscopy is a powerful tool in identifying different calcium carbonate polymorphs. Here, the method is applied to cultured pearls from freshwater (genus Hyriopsis) and marine bivalve species (Pinctada maxima) as well as to shells of Diplodon chilensis patagonicus bivalves. Raman spectra for vaterite, detected for the first time in an adult shell, and amorphous calcium carbonate (ACC) are discussed. Results for ACC are compared with those of synthetically produced ACC and with the Raman spectroscopic features of stable biogenic ACC from the crustacean Porcellio scaber. Decomposition of the most intense signal of all calcium carbonate polymorphs—the ν1 symmetric stretching mode of the carbonate ion—leads to the identification of two polymorphs within the ACC areas: a mixure of an amorphous and a crystalline fraction. The amorphous phase is characterised by a broad peak in the region of the lattice modes, which is composed of two distinct lattice modes with very high full‐widths at half‐maximum (FWHMs). The FWHMs of most of the crystalline fractions (in the range of 6.3–10.7 cm−1) are too high for well‐crystallised materials and support reports of nanocrystalline calcium carbonate polymorph clusters in ACC. Crystallinity indices of different samples are calculated and found to be useful to describe roughly the state of crystallisation in the ACC areas. Copyright © 2010 John Wiley & Sons, Ltd.
ADAM 10 is associated with gastric cancer progression and prognosis of patients
Authors: Wang Yuan‐Yu , Ye Zai‐Yuan , Li Li , Zhao Zhong‐Sheng , Shao Qin‐Shu , Tao Hou‐Quan
Published: November 2010

Background

The metalloproteinase domain‐containing protein 10 (ADAM 10) has been implicated in the development and progression of gastric cancer.

Methods

Expression of ADAM 10 and C‐erbB‐2 were examined immunochemically in 436 clinicopathologically characterized gastric cancer cases.

Results

Protein levels of ADAM 10 and C‐erbB‐2 were up‐regulated in gastric cancer lesions compared with adjacent non‐cancerous tissues. Positive expression of ADAM 10 correlated with age, size of tumor, location of tumor, depth of invasion, vessel invasion, lymph node, and distant metastasis and TNM stage, and also with expression of C‐erbB‐2. In stages I, II, and III, the 5‐year survival rate of patients with high ADAM 10 expression was significantly lower than in patients with low expression. However, in stage IV, ADAM 10 expression did not correlate with the 5‐year survival rate. Further multivariate analysis suggests that up‐regulation of ADAM 10 and C‐erbB‐2 were independent prognostic indicators for the disease, along with depth of invasion, lymph node and distant metastasis and TNM stage.

Conclusion

Expression of ADAM 10 in gastric cancer is significantly associated with lymph node and distant metastasis, high C‐erbB‐2 expression, and poor prognosis. ADAM 10 and C‐erbB‐2 proteins could be useful markers to predict tumor progression and prognosis. J. Surg. Oncol. 2011; 103:116–123. © 2010 Wiley‐Liss, Inc.
Impact of blood transfusion on early outcome of liver resection for colorectal hepatic metastases
Authors: Gruttadauria Salvatore , Saint Georges Chaumet Maureen , Pagano Duilio , Marsh J. Wallis , Bartoccelli Carlo , Cintorino Davide , Arcadipane Antonio , Vizzini Giovanni , Spada Marco , Gridelli Bruno
Published: November 2010

Background

The use of intra‐operative blood transfusion has been associated with worse surgical outcome in patients undergoing liver resection for malignancy.

Methods

In a series of 127 consecutive patients who underwent partial liver resection for colorectal metastases, between July 1999 and March 2010, we studied, post‐operative 90 days surgical outcome using Clavien multi‐tier grading system, and the effect of a variety of related factors, including type of resection, surgical technique used, concomitant colo‐rectal resection, non‐tumoral hepatic histological findings, site of primary tumor, and comorbidities, on the incidence of intra‐operative blood transfusion.

Results

Patients who received blood transfusions during their liver resection were more likely to have a longer post‐operative length of stay, to experience Clavien Grade IIIa or worse complication. Undergoing a major resection and the presence of portal fibrosis in the non‐tumoral liver tissue were both correlated with an increase in intra‐operative blood transfusions.

Conclusion

These clinical findings suggest that although several significant factors do not seem to influence the short‐term outcome of surgery, it is important to be aware of the deleterious effects of the type of resection performed and the presence of portal fibrosis on blood loss during partial liver resection. J. Surg. Oncol. 2011; 103:140–147. © 2010 Wiley‐Liss, Inc.
Breast cancer in elderly women (≥80 years): variation in standard of care?
Authors: Cyr Amy , Gillanders William E. , Aft Rebecca L. , Eberlein Timothy J. , Margenthaler Julie A.
Published: November 2010

Objective

The study aim was to investigate the methods of breast cancer diagnosis and treatment for women at advanced ages.

Methods

We identified 134 patients ≥80 years old treated for breast cancer. Data included patient and tumor characteristics, treatment, and outcomes.

Results

Of 134 women ≥80 years old, 146 breast cancers were diagnosed. Sixty‐five (45%) were detected by mammography. Surgical therapy included partial mastectomy in 50% and mastectomy in 50%. Although 12 (9%) women had no axillary staging, 22 (16%) underwent axillary lymph node dissection for node‐negative disease. Of 73 patients undergoing partial mastectomy, 34 (47%) received adjuvant radiation. Of 113 cancers with known estrogen receptor (ER) status, 83% were ER positive; 95% received endocrine therapy. Fourteen (10%) received adjuvant chemotherapy. Eleven (8%) were Her‐2neu‐amplified; one patient received adjuvant trastuzumab. At follow‐up, 87 (65%) patients were alive without evidence of disease, while 6 (4%) died of breast cancer.

Conclusions

Breast cancer in women ≥80 years is more likely to be early‐stage with favorable tumor biology. While most women eligible for anti‐estrogen therapy received it, adjuvant radiation, chemotherapy, and/or trastuzumab were utilized infrequently. Despite these variations, older women with breast cancer are unlikely to suffer breast cancer‐related mortality. J. Surg. Oncol. 2011; 103:201–206. © 2010 Wiley‐Liss, Inc.
XIAP‐associated factor 1 interacts with and attenuates the trans‐activity of four and a Half LIM protein 2
Authors: Zhang Wenjing , Yang Yi , Jiang Bo , Peng Junzhong , Tu Shuiping , Sardet Claude , Zhang Yusheng , Pang Roberta , Hung Ivan F , Tan V. P. Y. , Lam Colin SC , Wang Jide , Wong Benjamin C.Y.
Published: November 2010

XIAP‐associated factor 1(XAF1) is a tumor suppressor with its functional mechanisms not fully understood. The zinc‐finger cluster located at the N‐terminus is the only domain structure. Four and a half LIM domain protein 2 (FHL2) also contains a tandem zinc finger structure, and its protein functions as an important adaptor and modifier in protein–protein interactions. Both of their structures are relatively simple, while the association between them is still unclear. In this study, we detected the interaction between XAF1 and FHL2 by using the yeast two‐hybrid system. We identified FHL2 as a XAF1 binding protein. Furthermore, both XAF1 and FHL2 localized to the cytoplasm, mitochondria, and nucleus of gastric cancer cells. Over‐expression of XAF1 excluded FHL2 from the nucleus and suppressed the trans‐activity of FHL2 in stimulating the transcriptional activities of β‐catenin and AP‐1. In conclusion, our findings unraveled an antagonistic mechanism between a tumor suppressor and an oncoprotein in cancer cells. Mol. Carcinog. © 2010 Wiley‐Liss, Inc.
Dietary factors and pancreatic cancer: The role of food bioactive compounds
Authors: Johnson Jodee , de Mejia Elvira Gonzalez
Published: November 2010

Pancreatic cancer is the fourth leading cause of cancer mortality among both men and women in the United States with a 5‐year survival rate of only 4%. Several dietary factors may influence the risk of developing pancreatic cancer and its recurrence. Some of these factors may offer innovative therapies for prevention of this disease. The goal of this review is to provide an overview of pancreatic cancer, as well as current knowledge on the epidemiological, in vitro, in vivo, and clinical studies conducted about this disease using various dietary agents. The main focus is on food‐based approaches for preventing this disease particularly, citrus fruits, and foods containing flavonoids, curcumin, folate and vitamin D.
Fabric evolution within shear bands of granular materials and its relation to critical state theory
Authors: Fu Pengcheng , Dafalias Yannis F.
Published: November 2010

In an effort to study the relation of fabrics to the critical states of granular aggregates, the discrete element method (DEM) is used to investigate the evolution of fabrics of virtual granular materials consisting of 2D elongated particles. Specimens with a great variety of initial fabrics in terms of void ratios, preferred particle orientations, and intensities of fabric anisotropy were fabricated and tested with direct shear and biaxial compression tests. During loading of a typical specimen, deformation naturally localizes within shear bands while the remaining of the sample stops deforming. Thus, studying the evolution of fabric requires performing continuous local fabric measurements inside these bands, a suitable task for the proposed DEM methodology. It is found that a common ultimate/critical state is eventually reached by all specimens regardless of their initial states. The ultimate/critical state is characterized by a critical void ratio e which depends on the mean stress p, while the other critical state fabric variables related to particle orientations are largely independent of p. These findings confirm the uniqueness of the critical state line in the e − p space, and show that the critical state itself is necessarily anisotropic. Additional findings include the following: (1) shear bands are highly heterogeneous and critical states exist only in a statistical sense; (2) critical states can only be reached at very large local shear deformations, which are not always obtained by biaxial compression tests (both physical and numerical); (3) the fabric evolution processes are very complex and highly dependent on the initial fabrics. Copyright © 2010 John Wiley & Sons, Ltd.
Seismic wave propagation in laterally inhomogeneous poroelastic media via BIEM
Authors: Dineva Petia , Datcheva Maria , Manolis George , Schanz Tom
Published: November 2010

This work addresses in‐plane pressure P and vertically polarized shear SV seismic wave propagation in a finite, laterally inhomogeneous, multilayered poroelastic geological region resting on the homogeneous elastic half‐space. The particular approach followed here is based on a combination of the (i) viscoelastic approximation (isomorphism) to Biot's equations of dynamic poroelasticity and on the (ii) boundary integral equation method (BIEM) using frequency‐dependent fundamental solutions of the governing wave equations. The problem is formulated under plane strain conditions and time‐harmonic motions are assumed. Validation of the viscoelastic isomorphism and verification of the BIEM is done by solution of benchmark examples. These simulation studies reveal that the proposed methodology is able to depict a sensitivity of the seismic signals recovered to the following parameters: (i) poroelastic properties of fluid saturated layers; (ii) lateral geological inhomogeneity; (iii) surface topography and (iv) frequency content and direction of the incident wave. It is concluded that the combination of viscoelastic isomorphism with BIEM software provides an effective numerical tool for evaluating site‐effect phenomena in multilayered, fluid saturated geological regions with complex geometry. The numerical results obtained demonstrate that dynamic poroelasticity interacting with other physical peculiarities of the Earth's surface layers, such as lateral heterogeneity, material properties along the wave path, local geological profile and type of elastic wave, gives rise to complex seismic signals on the free surface at the site of interest. Copyright © 2010 John Wiley & Sons, Ltd.
Chronic chorioamnionitis displays distinct alterations of the amniotic fluid proteome
Authors: Oggé Giovanna , Romero Roberto , Lee Deug‐Chan , Gotsch Francesca , Than Nandor Gabor , Lee JoonHo , Chaiworapongsa Tinnakorn , Dong Zhong , Mittal Pooja , Hassan Sonia S , Kim Chong Jai
Published: November 2010

Acute chorioamnionitis of infectious origin and chronic chorioamnionitis of immunological origin are two major placental lesions of spontaneous preterm birth with elevated amniotic fluid interleukin‐6 and CXCL10 concentrations, respectively. The changes in the amniotic fluid proteome associated with intra‐amniotic infection and acute chorioamnionitis are well defined, yet alterations unique to chronic chorioamnionitis remain to be elucidated. This study was conducted to determine those amniotic fluid proteins changing specifically in the presence of chronic chorioamnionitis. Amniotic fluid obtained from acute chorioamnionitis, chronic chorioamnionitis and gestational age‐matched controls were analysed by two‐dimensional (2D) difference in gel electrophoresis and MALDI–TOF analyses. The type of histological inflammation was used to define each condition in preterm labour cases (n = 125) and term not in labour cases (n = 22), and the amniotic fluid concentrations of interleukin‐6, CXCL8, CXCL10 and prostaglandin F2α were also measured by specific immunoassays. Among preterm labour cases, 31 differentially expressed proteins were identified in chronic chorioamnionitis cases as compared to both acute chorioamnionitis and control cases. Importantly, glycodelin‐A, which maintains maternal tolerance against an allogeneic fetus, was decreased in chronic chorioamnionitis, while haptoglobin was increased. We report the amniotic fluid proteome of chronic chorioamnionitis for the first time, and the findings herein strongly suggest that there is a pathophysiological association between the changes of immunomodulatory proteins in the amniotic fluid and chronic chorioamnionitis, a histological manifestation of maternal anti‐fetal allograft rejection. Copyright © 2010 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Steric effects of substituents of quinones on the oxygenation of ethylbenzene catalyzed by NHPI/quinone and the catalytic oxidation of ascorbate
Authors: Yang Xiaomei , Wang Ying , Zhang Chaofeng , Fang Tao , Zhou Lipeng , Zhang Wei , Xu Jie
Published: November 2010

The substituents of quinones play an important role in modulating the kinetics of the electron‐ and proton‐transfer reaction. In this paper, the steric effects of substituents of quinones on their catalytic performance were studied in the oxidation of ethylbenzene and ascorbate. The substituents limited the addition of the free radicals to the CC double bonds of the quinone ring because of the steric hindrance. On the other hand, too many substituents hindered the contact between the active site (CO) of quinone and the reactant. So, the quinones with two substituents presented better catalytic performance than those with more or less substituents. These results will be helpful in designing the quinone compounds for drugs and in understanding the catalytic behavior of quinones in biochemistry. Copyright © 2010 John Wiley & Sons, Ltd.
Kinetics and mechanism of the anilinolysis of aryl 4‐nitrophenyl thionocarbonates in aqueous ethanol
Authors: Castro Enrique A. , Acevedo Rayen , Santos José G.
Published: November 2010

The reactions of bis(4‐nitrophenyl), 3‐chlorophenyl 4‐nitrophenyl, and 3‐methoxyphenyl 4‐nitrophenyl thionocarbonates (1, 2, and 3, respectively) with a series of anilines are subjected to a kinetic investigation in 44 wt.% ethanol–water, at 25.0 °C and an ionic strength of 0.2 M. Under aniline excess, pseudo‐first‐order rate coefficients (kobs) are found. Plots of kobs versus aniline concentration are linear, with the slopes (kN) pH independent, kN being the rate coefficient for the anilinolysis of the thionocarbonates. The Brønsted plot (log kN vs. pKa of anilinium ions) for thionocarbonate 1 is linear, with slope (β) 0.62, which is consistent with a concerted mechanism. The Brønsted plots for thionocarbonates 2 and 3 are curved, with slopes 0.1 at high pKa for both reaction series and slopes 0.84 and 0.79 at low pKa for the reactions of 2 and 3, respectively. The latter plots are in accordance to stepwise mechanisms, through a zwitterionic tetrahedral intermediate (T±) and its anionic analogue (T−), the latter being formed by deprotonation of T± by the basic form of the buffer (HPO). The Brønsted curves are explained by a change in the rate‐limiting step, from deprotonation of T± at low pKa, to its formation at high pKa. The influence of the amine nature and the non‐leaving and electrophilic groups of the substrate on the kinetics and mechanism is also discussed. Copyright © 2010 John Wiley & Sons, Ltd.
Preparation and Performances of Castable HTPB/CL‐20 Booster Explosives
Authors: Wang Jingyu , An Chongwei , Li Gang , Liang Lei , Xu Wenzheng , Wen Kun
Published: November 2010

HTPB/CL‐20 castable booster explosives were prepared successfully by a cast‐cured process. Scanning electron microscope (SEM) and the charge density test were employed to characterize the molding effect of HTPB/CL‐20 explosives. The propagation reliability, detonation velocity, mechanical sensitivity, thermal decomposition characteristics and thermal stability of the HTPB/CL‐20 explosives were also measured and analyzed. The results show that, when CL‐20 content is less than 91 wt.‐%, the charges with better molding effect were obtained easily. The critical diameter of HTPB/CL‐20 explosives is less than 1 mm, which exhibits good propagation reliability. When the density of HTPB/CL‐20 charge with 91 wt.‐% CL‐20 is 1.73 g cm−3, its detonation velocity can reach 8273 m s−1. Moreover, this kind of explosives has low mechanical sensitivity and good thermal stability.
PKCδ activation mediates angiogenesis via NADPH oxidase activity in PC‐3 prostate cancer cells
Authors: Kim Jeewon , Koyanagi Tomoyoshi , Mochly‐Rosen Daria
Published: November 2010

BACKGROUND

PKCδ is generally known as a pro‐apoptotic and anti‐proliferative enzyme in human prostate cancer cells.

METHODS

Here, we investigated the role of PKCδ on the growth of PC‐3 human prostate cancer cells in vivo and in vitro.

RESULTS

We found that sustained treatment with a specific PKCδ activator (ψδ receptor for active C kinase, ψδRACK) increased growth of PC‐3 xenografts. There was increased levels of HIF‐1α, vascular endothelial growth factor and CD31‐positive cells in PC‐3 xenografts, representative of increased tumor angiogenesis. Mechanistically, PKCδ activation increased the levels of reactive oxygen species (ROS) by binding to and phosphorylating NADPH oxidase, which induced its activity. Also, PKCδ‐induced activation of NADPH oxidase increased the level of HIF‐1α.

CONCLUSIONS

Our results using tumors from the PC‐3 xenograft model suggest that PKCδ activation increases angiogenic activity in androgen‐independent PC‐3 prostate cancer cells by increasing NADPH oxidase activity and HIF‐1α levels and thus may partly be responsible for increased angiogenesis in advanced prostate cancer. Prostate 71: 946–954, 2011. © 2010 Wiley‐Liss, Inc.
Nano‐hydroxyapatite colloid suspension coated on chemically modified porous silicon by cathodic bias: a suitable surface for cell culture
Authors: Sánchez Alejandra , González Jerson , García‐Piñeres Alfonso , Montero Mavis L.
Published: November 2010

The properties of porous silicon make it an interesting material for biological applications. However, porous silicon is not an appropriate surface for cell growth. Surface modification is an alternative that could afford a bioactive material. In this work, we report a method to yield materials by modification of the porous silicon surface with hydroxyapatite of nanometric dimensions, produced using an electrochemical process and coated on macroporous silicon substrates by cathodic bias.

The chemical nature of the calcium phosphate deposited on the substrates after the experimental process and the amount of cell growth on these surfaces were characterized. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Mechanism of photo catalytic degradation of Brilliant Blue colorant in water suspension with TiO2 catalyst
Authors: Cortes J. A. , Pérez‐Robles J. F. , González‐Hernández J. , Vorobiev P. , Vorobiev Y. V. , García A. G.
Published: November 2010

Water purification by photo catalytic decomposition of Brilliant Blue colorant in water suspension was studied. This work presents experimental and theoretical results in which the mechanism is discussed of decomposition of an organic colorant’s molecule. In theoretical part, a calculation of the energy levels of the molecule and its parts derived in decomposition process based on modified FEMO modeling confirm the mechanism proposed (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Study of macroporous silicon electrochemical etching in 3D structured N type silicon substrates
Authors: Kouassi Sebastien , Gautier Gael , Desplobain Sebastien , Ventura Laurent
Published: November 2010

In this paper, the electrochemical etching of 3D n‐type substrates is investigated. These types of 3D structures are of interest to increase the active surface of some systems. Our aim is to improve a MEMS (Micro‐Electro Mechanical System) micro fuel cell power through total surface enhancement without any modification of the cell footprint. To reach this objective, we perform a gas diffusion layer using localized macro‐porous silicon. The porous area total surface is improved through trench formation (before porous silicon etching). This is supposed to allow a better power to surface ratio for manufactured fuel cell. The Figure on the right hand side introduces the aimed MEMS based micro fuel cell. The geometrical parameters of the designed structures and the manufacturing process influence are presented. To perform 3D structures, two types of anisotropic etching techniques have been used, alkaline etching of silicon and deep reactive ion etching (DRIE). Additional steps such as a doping layer have been used to improve the results obtained with the initial micro‐fabrication process. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Gradient TiO2 nanotube arrays
Authors: Cheng Jian‐Wen , Tsang Chun Kwan , Liang Fengxia , Cheng Hua , Li Yang Yang
Published: November 2010

Gradient TiO2 nanotube arrays were fabricated by anodization using an asymmetric electrode configuration. The nanotube arrays thus obtained display a gradually changing distribution of tube diameters and length across the sample plane. The application of the fabricated gradient TiO2 nanotube arrays as optical sensors is also demonstrated. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Efficient nanostructure modified interfaces for array‐based sensing based on the novel application of hard/soft acid/base interactions
Authors: Gole James L. , Ozdemir Serdar
Published: November 2010

With a focus to develop array‐based sensor systems, select micro/nanoporous porous silicon (PS) interfaces have been formed and treated with a variety of nanostructured oxides to create an array of sensor responses for a variety of gases. A general model for the highly active and varied sensitivity of these treated interfaces is presented. This model, which takes advantage of the playoff between chemical bonding and physical adsorption to the deposited nanostructured oxides, suggests a means to selectively enhance the response to basic analyte gases by enhancing the reversible resistance increase characteristic of the response of p‐type silicon. The approach, counter to that used to promote strong interaction and chemical bond formation via hard and soft acid and base interactions (HSAB), promotes the enhancement of physisorption by applying an inverse concept. The focus, in applying the IHSAB model to the interaction of gaseous bases with the acidic nanostructure treated or untreated PS surface, is the minimization of chemical bonding and the maximization of electron transfer to the PS‐based interface, thus increasing the resistance response. The model shows potential to create array‐based devices. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Matrix metalloproteinase sensing via porous silicon microcavity devices functionalized with human antibodies
Authors: Martin Marta , Taleb Bendiab Chakib , Massif Laurent , Palestino Gabriela , Agarwal Vivechana , Cuisinier Frédéric , Gergely Csilla
Published: November 2010

Porous silicon microcavity (PSiMc) structures were used as support material for specific sensing of matrix metalloproteinases (MMPs). For lower concentrations of MMP‐8, the structures were tested with two types of functionalization methods. Silanization of the oxidized porous silicon structures, followed by glutaraldehyde chemistry was found to give very inconsistent results. The use of biotinilated bovin serum albumin linked to the naked PSiMc was found to be an alternative method to attach the anti MMP‐8 human antibody, previously modified with streptavidin, which was further used to sense MMP‐8 (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
An analytical drain current model for undoped GSDG MOSFETs including interfacial hot‐carrier effects
Authors: Djeffal Fayçal , Bentrcia Toufik , Bendib Toufik
Published: November 2010

In the present work, a comprehensive drain current model including the interfacial hot‐carrier degradation effects for undoped symmetric gate stack double gate (GSDG) MOSFET and the expressions of transconductance and drain conductance have been obtained. Exploiting this new device model, we have found that the incorporation of a high‐k layer between oxide region and gate metal leads to drain current enhancement, improved output conductance, increased transconductance parameter and enhanced interfacial hot‐carrier immunity. The proposed model has been validated by comparing the analytical I‐V characteristics with 2‐D numerical results. The obtained results may provide a theoretical basis and physical insights for multigate MOSFET‐based circuits design including the hot‐carrier degradation effects. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The formation of near surface SiGe layers with combined high‐dose ion implantation and flash‐lamp annealing
Authors: Voelskow Matthias , Stoimenos Ioannis , Rebohle Lars , Skorupa Wolfgang
Published: November 2010

The formation of near surface SiGe layers by means of combined high dose Ge ion implantation and flash lamp annealing will be addressed. Furthermore, we show that the formation of an undesirable facetted liquid/solid interface, which is well known for pulse melting in the millisecond time regime, is less pronounced due to the decreasing melting temperature of Si with increasing Ge concentration at the SiGe/Si interface. A dislocation network, which is observed by using transmission electron microscopy, is expected to play an important role to form these thin SiGe layers. We will demonstrate the depth profiles of Ge by Rutherford backscattering spectrometry and discuss the concerned mechanism. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Defects formed by pulsed laser annealing: electrical properties and depth profiles in n‐type silicon measured by deep level transient spectroscopy
Authors: Schindele David , Pichler Peter , Lorenz Jürgen , Oesterlin Peter , Ryssel Heiner
Published: November 2010

The ongoing downscaling of microelectronic devices requires dopant activation with diffusion kept to a minimum. One method considered in device processing is microsecond annealing by pulsed lasers. This is a highly non‐equilibrium process during which intrinsic point defects generated at the surface diffuse into the material and form a variety of defects during cooling‐down. Since the defects lie close to the surface, they may well affect the effective concentration and the formation of leakage currents in pn‐junctions of advanced technologies. These defects may be clusters of intrinsic point defects or contain residual impurities like oxygen or dopants.

In this work, a bare n‐type silicon substrate (phosphorus concentration 5 × 1014 cm–3) was annealed with a pulsed laser with maximum temperatures of about 800 K up to 1650 K. The defects remaining after annealing were characterized by deep level transient spectroscopy (DLTS) to obtain their activation energies and capture cross‐sections for majority carriers in n‐type silicon. Additionally, the depth profiles of these defects were measured via a variation of the pulse voltage. The dominating defects found have levels at EC – 0.41 eV, EC – 0.31 eV, EC – 0.3 eV, EC – 0.22 eV, and EC – 0.17 eV. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Gettering of iron in CZ‐silicon by polysilicon layer
Authors: Haarahiltunen A. , Yli‐Koski M. , Talvitie H. , Vähänissi V. , Lindroos J. , Savin H.
Published: November 2010

We have studied iron gettering in intentionally iron contaminated Czochralski silicon wafers with a polysilicon layer. We have compared the gettering effect of the poly‐layer with internal gettering during a slow cooling from a high temperature. The experimental results show that the gettering efficiency of the polysilicon layer is stronger than internal gettering by bulk micro defects. In addition, the results reveal that after iron contamination and following surface cleaning, the polysilicon layer remains as a significant contamination source compared to a bare silicon surface. We also suggest a model for polysilicon gettering, which we use to analyze the dominant gettering mechanism under various gettering conditions (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Atomic‐layer‐deposited Ir thin film as a novel diffusion barrier layer in Cu interconnection
Authors: Lim Yong Hwan , Yoo Hana , Choi Bum Ho , Lee Jong Ho , Lee Ho‐Nyun , Lee Hong Kee
Published: November 2010

Atomic‐layer‐deposited iridium (Ir) thin films were successfully grown on a silicon substrate using Ir(EtCp)(COD) and oxygen as precursors between 240 and 420 °C. The optimal temperature range for the formation of a smooth and uniform Ir thin film was obtained. At 330 °C, specific ALD process conditions were found to yield a smooth Ir thin film with a thickness of 12 nm. The growth mechanism of ALD iridium thin films was investigated as a function of deposition cycle. In the early stage of ALD growth, Ir firstly nucleated after 100 cycles and continuous films of Ir fully covered the silicon substrate after 300 deposition cycles. These results indicate that the Ir ALD process has a long incubation period in contrast with other general ALD processes (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Anomalous temperature behaviour of band to band electroluminescence in silicon solar cells
Authors: Klossek A. , Arguirov T. , Mchedlidze T. , Kittler M.
Published: November 2010

A temperature dependence of intensity for band to band (BB) luminescence of a solar cell excited by constant current in forward biasing was investigated. The obtained temperature dependence is untypical for silicon, i.e. the intensity of the BB luminescence increases with temperature. We analyse our results in view of thermally induced change of excess carrier concentration. Two temperature dependent nonradiative recombination processes limit the carrier concentration. One is the recombination in the bulk, mediated by deep impurity levels and the other is the surface recombination. The surface recombination limits the minority carrier diffusion length to the thickness of the solar cell. We show that the interference of both recombination processes causes the effective lifetime to increase upon increasing temperature. Thereby the deep level mediated recombination dominates at high temperature, whilst the surface recombination is dominant at low temperatures. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Quantitative analysis of impurities in solar‐grade Si by photoluminescence spectroscopy around 20 K
Authors: Iwai Takaaki , Tajima Michio , Ogura Atsushi
Published: November 2010

We report details about the quantitative analysis of B and P impurities in the concentration range between 1 × 1014 and 1 × 1017 cm–3 by photoluminescence (PL) in solar‐grade Si (SOG‐Si). The intensity ratio of impurity‐bound exciton (BE) to free exciton (FE) at 4.2 K was used as a measure of the impurity concentration in the range between 5 × 1010 and 1 × 1015 cm–3 in the standard PL method. We raised the sample temperature to enhance the FE emission, which enabled us to extend the concentration range higher. The sample temperature was accurately determined from the FE‐line shape. We deduced a formula for the determination of the B and P concentrations in the higher range from the BE/FE ratio and the sample temperature (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Design of three‐component one‐dimensional photonic crystals with tuning of optical contrast and regions of transparency
Authors: Perova Tatiana S. , Tolmachev Vladimir A. , Baldycheva Anna
Published: November 2010

This paper is focused on the design and optical characterization of the three‐component tunable photonic crystal structures based on grooved silicon, serving as one‐dimensional (1D) photonic crystal (PC), with additional regular layer. The manipulation of the optical contrast to a high degree of precision by varying the thickness and refractive index of the additional third layer is obtained. The principle of suppression of the reflection bands and replacing them with regions of transparency is demonstrated for a high contrast 1D PC for the first time. The regions of transparency obtained show a high transmission value (> 0.99) and a substantial band width. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A novel technique for localized formation of SOI active regions
Authors: Veeramachaneni Bharat , Winans Joshua D. , Hu Shaoting , Kawamura Daiji , Fauchet Philippe M. , Witt Kevin , Hirschman Karl D.
Published: November 2010

In this work we study the role of fluorine for the selective suppression of porous silicon in localized SOI applications. The formation of porous silicon can be done selectively by controlling the Fermi level in areas to be etched or not etched, which is typically done by adjusting the level of doping. Implanted fluorine in silicon has demonstrated a donor effect upon annealing at low temperature (600 °C), which is reversible as the fluorine outdiffuses during higher temperature annealing (1100 °C). The investigated technique has been used to form crystalline silicon active regions with thickness less than 200 nm completely surrounded by oxidized porous silicon. The electronic integrity of the active area has also been established through nMOS transistor fabrication and characterization (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Double‐sided porous silicon as template for metal deposition
Authors: Rumpf Klemens , Granitzer Petra , Poelt Peter , Albu Mihaela
Published: November 2010

Mesoporous silicon, achieved by etching of a highly n‐doped wafer is used as template for electrochemical metal deposition. The fabrication of porous silicon samples with a porous layer on each side is performed in a double tank electrolytic cell in applying a pulsed current with a frequency of typically 0.1 Hz. Ferromagnetic metals such as Ni and Co are deposited into the pores of the matrices, either the same metal on both sides of the sample, a different metal on each side or an alloy of both. As substrate material also ultrathin silicon wafers with an average thickness of 60 µm are used to achieve a thickness as small as possible of the remaining bulk silicon in between the two porous layers. These fragile templates are also filled with transition metals and investigated magnetically. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Thin Multilayer Films and Microcapsules Containing DNA Quadruplex Motifs
Authors: Cavalieri Francesca , Ng Sher Leen , Mazzuca Claudia , Jia Zhongfan , Bulmus Volga , Davis Thomas P. , Caruso Frank
Published: November 2010

The assembly of multifunctional nanostructures bearing G‐quadruplex motifs broadens the prospects of using G‐quadruplexes as therapeutic carriers. Herein, we report the synthesis and characterization of an oligodeoxyguanosine, G15‐mer polymer conjugate. We demonstrate that G15‐mer oligonucleotides grafted to a polymer chain preserve the ability to self‐assemble into ordered structures. The G‐quadruplex‐polymer conjugates were assembled onto a surface via hybridization with 30‐mer cytosine strands, C30‐mer, using a layer‐by‐layer approach to form microcapsules. A mechanism for the sequential assembly of the multilayer films and microcapsules is presented. We further investigate the photophysical behavior of porphyrin TMPyP4 bound to multilayer‐coated particles. This study shows that the multilayer films bear residual and functional quadruplex moieties that can be used to effectively bind therapeutic agents.
Osteoblasts Derived from Induced Pluripotent Stem Cells form Calcified Structures in Scaffolds Both In Vitro and In Vivo
Authors: Bilousova Ganna , Jun Du Hyun , King Karen B. , De Langhe Stijn , Chick Wallace S. , Torchia Enrique C. , Chow Kelsey S. , Klemm Dwight J. , Roop Dennis R. , Majka Susan M.
Published: November 2010

Reprogramming somatic cells into an ESC-like state, or induced pluripotent stem (iPS) cells, has emerged as a promising new venue for customized cell therapies. In this study, we performed directed differentiation to assess the ability of murine iPS cells to differentiate into bone, cartilage, and fat in vitro and to maintain an osteoblast phenotype on a scaffold in vitro and in vivo. Embryoid bodies derived from murine iPS cells were cultured in differentiation medium for 8–12 weeks. Differentiation was assessed by lineage-specific morphology, gene expression, histological stain, and immunostaining to detect matrix deposition. After 12 weeks of expansion, iPS-derived osteoblasts were seeded in a gelfoam matrix followed by subcutaneous implantation in syngenic imprinting control region (ICR) mice. Implants were harvested at 12 weeks, histological analyses of cell and mineral and matrix content were performed. Differentiation of iPS cells into mesenchymal lineages of bone, cartilage, and fat was confirmed by morphology and expression of lineage-specific genes. Isolated implants of iPS cell-derived osteoblasts expressed matrices characteristic of bone, including osteocalcin and bone sialoprotein. Implants were also stained with alizarin red and von Kossa, demonstrating mineralization and persistence of an osteoblast phenotype. Recruitment of vasculature and microvascularization of the implant was also detected. Taken together, these data demonstrate functional osteoblast differentiation from iPS cells both in vitro and in vivo and reveal a source of cells, which merit evaluation for their potential uses in orthopedic medicine and understanding of molecular mechanisms of orthopedic disease.
Concise Review: Bone Marrow for the Treatment of Spinal Cord Injury: Mechanisms and Clinical Applications
Authors: Wright Karina T. , Masri Wagih El , Osman Aheed , Chowdhury Joy , Johnson William E. B.
Published: November 2010

Transplantation of bone marrow stem cells into spinal cord lesions enhances axonal regeneration and promotes functional recovery in animal studies. There are two types of adult bone marrow stem cell; hematopoietic stem cells (HSCs), and mesenchymal stem cells (MSCs). The mechanisms by which HSCs and MSCs might promote spinal cord repair following transplantation have been extensively investigated. The objective of this review is to discuss these mechanisms; we briefly consider the controversial topic of HSC and MSC transdifferentiation into central nervous system cells but focus on the neurotrophic, tissue sparing, and reparative action of MSC grafts in the context of the spinal cord injury (SCI) milieu. We then discuss some of the specific issues related to the translation of HSC and MSC therapies for patients with SCI and present a comprehensive critique of the current bone marrow cell clinical trials for the treatment of SCI to date.
FUS-CHOP Fusion Protein Expression Coupled to p53 Deficiency Induces Liposarcoma in Mouse but Not in Human Adipose-Derived Mesenchymal Stem/Stromal Cells
Authors: Rodriguez Rene , Rubio Ruth , Gutierrez-Aranda Ivan , Melen Gustavo J. , Elosua Carolina , García-Castro Javier , Menendez Pablo
Published: November 2010

Human sarcomas have been modeled in mice by expression of specific fusion genes in mesenchymal stem cells (MSCs). However, sarcoma models based on human MSCs are still missing. We attempted to develop a model of liposarcoma by expressing FUS (FUsed in Sarcoma; also termed TLS, Translocated in LipoSarcoma)-CHOP (C/EBP HOmologous Protein; also termed DDIT3, DNA Damage-Inducible Transcript 3), a hallmark mixoid liposarcoma-associated fusion oncogene, in wild-type and p53-deficient mouse and human adipose-derived mesenchymal stem/stromal cells (ASCs). FUS-CHOP induced liposarcoma-like tumors when expressed in p53−/− but not in wild-type (wt) mouse ASCs (mASCs). In the absence of FUS-CHOP, p53−/− mASCs forms leiomyosarcoma, indicating that the expression of FUS-CHOP redirects the tumor genesis/phenotype. FUS-CHOP expression in wt mASCs does not initiate sarcomagenesis, indicating that p53 deficiency is required to induce FUS-CHOP-mediated liposarcoma in fat-derived mASCs. In a human setting, p53-deficient human ASCs (hASCs) displayed a higher in vitro growth rate and a more extended lifespan than wt hASCs. However, FUS-CHOP expression did not induce further changes in culture homeostasis nor initiated liposarcoma in either wt or p53-depleted hASCs. These results indicate that FUS-CHOP expression in a p53-deficient background is sufficient to initiate liposarcoma in mouse but not in hASCs, suggesting the need of additional cooperating mutations in hASCs. A microarray gene expression profiling has shed light into the potential deregulated pathways in liposarcoma formation from p53-deficient mASCs expressing FUS-CHOP, which might also function as potential cooperating mutations in the transformation process from hASCs.
Human Placenta-Derived Adherent Cells Prevent Bone loss, Stimulate Bone formation, and Suppress Growth of Multiple Myeloma in Bone
Authors: Li Xin , Ling Wen , Pennisi Angela , Wang Yuping , Khan Sharmin , Heidaran Mohammad , Pal Ajai , Zhang Xiaokui , He Shuyang , Zeitlin Andy , Abbot Stewart , Faleck Herbert , Hariri Robert , Shaughnessy John D. , van Rhee Frits , Nair Bijay , Barlogie Bart , Epstein Joshua , Yaccoby Shmuel
Published: November 2010

Human placenta has emerged as a valuable source of transplantable cells of mesenchymal and hematopoietic origin for multiple cytotherapeutic purposes, including enhanced engraftment of hematopoietic stem cells, modulation of inflammation, bone repair, and cancer. Placenta-derived adherent cells (PDACs) are mesenchymal-like stem cells isolated from postpartum human placenta. Multiple myeloma is closely associated with induction of bone disease and large lytic lesions, which are often not repaired and are usually the sites of relapses. We evaluated the antimyeloma therapeutic potential, in vivo survival, and trafficking of PDACs in the severe combined immunodeficiency (SCID)–rab model of medullary myeloma-associated bone loss. Intrabone injection of PDACs into nonmyelomatous and myelomatous implanted bone in SCID-rab mice promoted bone formation by stimulating endogenous osteoblastogenesis, and most PDACs disappeared from bone within 4 weeks. PDACs inhibitory effects on myeloma bone disease and tumor growth were dose-dependent and comparable with those of fetal human mesenchymal stem cells (MSCs). Intrabone, but not subcutaneous, engraftment of PDACs inhibited bone disease and tumor growth in SCID-rab mice. Intratumor injection of PDACs had no effect on subcutaneous growth of myeloma cells. A small number of intravenously injected PDACs trafficked into myelomatous bone. Myeloma cell growth rate in vitro was lower in coculture with PDACs than with MSCs from human fetal bone or myeloma patients. PDACs also promoted apoptosis in osteoclast precursors and inhibited their differentiation. This study suggests that altering the bone marrow microenvironment with PDAC cytotherapy attenuates growth of myeloma and that PDAC cytotherapy is a promising therapeutic approach for myeloma osteolysis.
Lecture speech recognition using discrete‐mixture HMMs
Authors: Kosaka Tetsuo , Yamamoto Akiyoshi , Kumakura Takuya , Kato Masaharu , Kohda Masaki
Published: November 2010

Most of the state‐of‐the‐art speech recognition systems use continuous‐mixture hidden Markov models (CMHMMs) as acoustic models. On the other hand, it is well known that discrete hidden Markov model (DHMM) systems show poor performance because they are affected by quantization distortion. In this paper, we present an efficient acoustic modeling based on discrete distribution for large‐vocabulary continuous speech recognition (LVCSR). In our previous work, we proposed the maximuma posteriori(MAP) estimation of discrete‐mixture hidden Markov model (DMHMM) parameters and showed that the DMHMM system performed better in noisy conditions than the conventional CMHMM system. However, we conducted the recognition experiments on a read/speech task in which the vocabulary size was only 5k. In addition, the DMHMM was not effective in clean condition in that work. In this paper, we have developed a DMHMM‐based LVCSR system and evaluated the system on a more difficult task under clean condition. In Japan, a large‐scale spontaneous speech database ‘Corpus of Spontaneous Japanese’ has been used as the common evaluation database for spontaneous speech and we used it for our experiments. From the results, it was seen that the DMHMM system showed almost the same performance as the CMHMM system. Moreover, performance improvement could be achieved by a histogram equalization method. Copyright © 2010 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.