bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cryptanalysis of a certificateless signature scheme without pairings
Authors: Tian Miaomiao , Huang Liusheng 
Published: February 2012

SUMMARYCertificateless cryptography is an attractive paradigm for public key cryptography as it does not require certificates in traditional public key cryptography and, at the same time, solves the inherent key escrow problem in identity‐based cryptography. Recently, an efficient certificateless signature scheme without using pairings was proposed by He, Chen and Zhang. They claimed that it is provably secure under the discrete logarithm assumption in the random oracle model. However, in this paper, we show that their scheme is insecure against a type II adversary who can access to the master secret key of the system. Copyright © 2012 John Wiley & Sons, Ltd.
Code division multiple access/pulse position modulation ultra‐wideband radio frequency identification for Internet of Things: concept and analysis
Authors: Zhang Zhi , Lu Zhonghai , Chen Qiang , Yan Xiaolang , Zheng Li-Rong 
Published: February 2012

SUMMARYRadio frequency identification (RFID) is a compelling technology for Internet of Things (IoT). Ultra‐wideband (UWB) technology is one promising wireless technique for future RFID, especially for high‐throughput sensing applications. On‐off keying UWB RFID system provides high pulse rate but suffers severe collisions that limit the system throughput. This paper proposes to utilize low pulse rate code division multiple access/pulse position modulation UWB in the tag‐to‐reader link to provide multiple tag access capability and build a high‐throughput RFID system for IoT. We analyze asynchronous matched filter receiver and decorrelating receiver for multi‐tag detection and design an effective medium access control scheme to optimize the network throughput. We propose an effective dynamic frame size adjustment algorithm on the basis of theoretical analysis and determine the preferable length of Gold codes. With a similar data rate, the throughput of the proposed system using the decorrelating receiver is 8.6 times higher than that of the electronic product code class 1 generation 2 system. Only using 1/10 pulse rate and 1/15 data rate, the proposed system outperforms the on‐off keying UWB RFID system 1.4 times in terms of throughput. Copyright © 2012 John Wiley & Sons, Ltd.
Evaluation of experimental genetic management in reintroduced bighorn sheep
Authors: Olson Zachary H. , Whittaker Donald G. , Rhodes Olin E. 
Published: February 2012

AbstractPositive demographic responses have been reported in several species where the immigration or supplementation of genetically distinct individuals into wild populations has resulted in a genetic rescue effect. However, rarely have researchers incorporated what could be considerable risk of outbreeding depression into planning for genetic management programs. We assess the genetic effects of an experiment in genetic management involving replicate populations of California bighorn sheep (Ovis canadensis californiana) in Oregon, USA, which previously experienced poor productivity and numerical declines. In the experiment, two declining populations were supplemented with ewes from a more genetically diverse population of California bighorn sheep in Nevada. We incorporated analysis of genetic samples representing both experimental populations prior to supplementation, samples from the supplemented individuals, and samples collected from both experimental populations approximately one generation after supplementation. We used genetic analyses to assess the integration of supplemented and resident populations by identifying interpopulation hybrids. Further, we incorporated demographic simulations to assess the risk of outbreeding depression as a result of the experimental augmentation. Finally, we used data from microsatellites and mitochondrial sequences to determine if genetic management increased genetic diversity in the experimental populations. Our analyses demonstrated the success of genetic management by documenting interpopulation hybrids, identifying no evidence for outbreeding depression as a result of contact between the genetically distinct supplemented and resident populations, and by identifying increased population‐level metrics of genetic diversity in postsupplementation populations compared with presupplementation levels.
Equimolar mixture of c9,t11 and t9,t11 CLA inhibits the growth and induces apoptosis in Caco‐2 cells
Authors: Zhong Xian‐Feng , Luo Ting , Huang Gui‐Dong , Deng Ze‐Yuan , Lei Lin 
Published: February 2012

AbstractIn 2008, CLAs received a no‐objection letter from the FDA on its generally recognized as safe (GRAS) status for certain foods. However, aside from the mixture of c9, t11‐CLA and t10, c12‐CLA, other CLA mixtures are still not used in food production. The effects of different concentrations (25, 50, 100, and 200 µmol/L) of CLA mixture (c9, t11‐CLA and t9, t11‐CLA) on the human colorectal carcinoma cell line Caco‐2 cells after various treatment times (1, 2, 3, and 4 days) and the induced apoptosis were examined in the study. The mRNA expression level and activities of caspase‐3, ‐8, and ‐9 were determined via quantitative real‐time PCR and caspase‐3, ‐8, and ‐9 assay kits. The results indicated that the CLA mixture inhibited the proliferation of the Caco‐2 cells, and the antiproliferative effects were closely related to treatment time and concentration. Meanwhile, the CLA mixture increased the mRNA expression level and activities of caspase‐3, ‐8, and ‐9 compared with control which suggested apoptosis induced by CLA mixture was related to the caspase pathway. In conclusion, the CLA mixture can inhibit Caco‐2 cell proliferation and induce its apoptosis through increasing caspase 3, 8, and 9 expression and activities.Practical applications: In the food industry, lactic acid bacteria (LAB) are generally recognized as safe and important for the production of fermented food and may be used as probiotic bacteria in the human gastrointestinal tract, contributing to pathogen inhibition and immunomodulation. C9, t11‐CLA and t9, t11‐CLA isomers used for the present study were obtained from the conversion of linoleic acid by Lactobacillus helveticus L7 (used as a probiotic bacterial in our laboratory). Here, the mixture of c9, t11‐CLA and t9, t11‐CLA had a synergistic antiproliferation effect on the Caco‐2 cells which suggested that the CLA mixture has potential health value, and can be a beneficial supplement in the food industry.
Comparison of aneuploidies of chromosomes 21, X, and Y in the blood lymphocytes and sperm of workers exposed to benzene
Authors: Ji Zhiying , Weldon Rosana H. , Marchetti Francesco , Chen Howard , Li Guilan , Xing Caihong , Kurtovich Elaine , Young Suzanne , Schmid Thomas E. , Waidyanatha Suramya , Rappaport Stephen , Zhang Luoping , Eskenazi Brenda 
Published: February 2012

AbstractBenzene is a primary industrial chemical and a ubiquitous environmental pollutant that causes human leukemia and maybe other malignancies. Occupational exposure to benzene has been associated with increased chromosomal aneuploidies in blood lymphocytes and, in separate studies, in sperm. However, aneuploidy detection in somatic and germ cells within the same benzene‐exposed individuals has never been reported. To compare aneuploidies in blood lymphocytes and sperm within the same individuals exposed to benzene, a cross‐sectional study was conducted in 33 benzene‐exposed male workers and 33 unexposed workers from Chinese factories. Air benzene concentrations in the exposed workers ranged from below the detection limit to 24 ppm (median, 2.9 ppm) and were undetectable in the unexposed subjects. Aneuploidies of chromosomes 21, X, and Y in blood lymphocytes were examined by multicolor fluorescence in situ hybridization and were compared to the previously reported aneuploidies in sperm. The results showed that benzene exposure was positively associated with the gain of chromosome 21 but not sex chromosomes in blood lymphocytes. This was in contrast to analysis of sperm, where the gain of sex chromosomes, but not chromosome 21, was significantly increased in the exposed workers. Furthermore, a significant correlation in the gain of sex chromosomes between blood lymphocytes and sperm was observed among the unexposed subjects, but not among the exposed workers. The findings suggest that benzene exposure induces aneuploidies in both blood cells and sperm within the same individuals, but selectively affects chromosome 21 in blood lymphocytes and the sex chromosomes in sperm. Environ. Mol. Mutagen. 2012. © 2011 Wiley Periodicals, Inc.
Nardilysin and ADAM proteases promote gastric cancer cell growth by activating intrinsic cytokine signalling via enhanced ectodomain shedding of TNF‐α
Authors: Kanda Keitaro , Komekado Hideyuki , Sawabu Tateo , Ishizu Shoko , Nakanishi Yuki , Nakatsuji Masato , Akitake‐Kawano Reiko , Ohno Mikiko , Hiraoka Yoshinori , Kawada Mayumi , Kawada Kenji , Sakai Yoshiharu , Matsumoto Kyoichi , Kunichika Makoto , Kimura Takeshi , Seno Hiroshi , Nishi Eiichiro , Chiba Tsutomu 
Published: February 2012

AbstractNardilysin (NRDc), a metalloendopeptidase of the M16 family, promotes ectodomain shedding of the precursor forms of various growth factors and cytokines by enhancing the protease activities of ADAM proteins. Here, we show the growth‐promoting role of NRDc in gastric cancer cells. Analyses of clinical samples demonstrated that NRDc protein expression was frequently elevated both in the serum and cancer epithelium of gastric cancer patients. After NRDc knockdown, tumour cell growth was suppressed both in vitro and in xenograft experiments. In gastric cancer cells, NRDc promotes shedding of pro‐tumour necrosis factor‐alpha (pro‐TNF‐α), which stimulates expression of NF‐κB‐regulated multiple cytokines such as interleukin (IL)‐6. In turn, IL‐6 activates STAT3, leading to transcriptional upregulation of downstream growth‐related genes. Gene silencing of ADAM17 or ADAM10, representative ADAM proteases, phenocopied the changes in cytokine expression and cell growth induced by NRDc knockdown. Our results demonstrate that gastric cancer cell growth is maintained by autonomous TNF‐α–NF‐κB and IL‐6–STAT3 signalling, and that NRDc and ADAM proteases turn on these signalling cascades by stimulating ectodomain shedding of TNF‐α.
The response of saltation to wind speed fluctuations
Authors: Pfeifer Sascha , Schönfeldt Hans‐Jürgen 
Published: February 2012

ABSTRACTThe response time of saltation to spatial or temporal wind speed fluctuations constitutes an important control parameter for aeolian sediment transport and deposition. In this paper, we present direct measurements of the response time obtained from several field experiments.The sand transport was studied using six small microphones arranged in a vertical profile and collocated with a sonic anemometer, a webcam and a cup anemometer tower. The webcam was coupled with the sonic anemometer via a personal computer and provides information on creeping and saltating grains with a sampling rate of 10 Hz. Sediment transport measurements were obtained over four periods.The Wiener filter, a signal processing technique, is used to obtain a discrete transfer function that relates the horizontal wind speed and the non‐intermittent sand transport. The transfer function can be established using an exponential function with a time constant or characteristic response time τ without time shift. The response time fluctuated between zero and 1·5 seconds depending on the turbulence intensity, the saltation activity, the measuring height and sampling rates. The Wiener filter coefficients suggest that the response of saltation to wind speed alterations is determined by more than one process. Copyright © 2012 John Wiley & Sons, Ltd.
Thermal stress–strain of self‐compacting concrete in compression
Authors: Tao Jin , Yuan Yong , Taerwe Luc 
Published: February 2012

ABSTRACTSelf‐compacting concrete or self‐consolidation concrete (SCC) is being used in underground and other industrial structures that may be subjected to high temperatures during operation or in case of an accidental fire. The proper understanding of the effects of elevated temperatures on the stress–strain relationship of SCC is necessary in the assessment of structural safety. This paper presents the high temperature behavior from an experimental study carried out on SCC subjected to high temperatures. The effects of temperature, strength grade, and polypropylene (PP) fibers on the initial elastic modulus, strain at peak stress, and stress–strain curves of SCC are studied, which offered a test basis for estimating the deformation of SCC under high temperature. An empirical constitutive formula for the thermal stress–strain of SCC is developed on the basis of the deformation characteristics of PP fiber‐modified SCC. Copyright © 2012 John Wiley & Sons, Ltd.
Essential oil of Plectranthus tenuicaulis for flavour and fragrance: Synthesis of derivatives from natural and synthetic 6,7‐epoxyocimenes
Authors: Agrebi Abdelhamid , Agnaniet Huguette , Bikanga Raphaël , Makani Thomas , Anguilé Jean Jacques , Lebibi Jacques , Casabianca Hervé , Morère Alain , Menut Chantal 
Published: February 2012

ABSTRACT(R)‐(E)‐6,7‐Epoxyocimene, the major constituent of the essential oil from Plectranthus tenuicaulis, as well as the racemic (Z)‐isomer previously synthesized from commercial (Z)‐β‐ocimene were used as starting material for the synthesis of fragrant derivatives. Among the 14 compounds obtained from these precursors (alcohols, diols, diepoxy, sulfur and carbonyl derivatives), four were described for the first time and three were enantiomerically pure. All compounds were fully characterized by one‐ and two‐dimensional nuclear magnetic resonance analysis as well as by gas chromatography and mass spectroscopy (electron ionization). Additionally, their odour properties were evaluated. Copyright © 2012 John Wiley & Sons, Ltd.
High risk of non‐sentinel node metastases in a group of breast cancer patients with micrometastases in the sentinel node
Authors: Tvedskov Tove Filtenborg , Jensen Maj‐Britt , Lisse Ida Marie , Ejlertsen Bent , Balslev Eva , Kroman Niels 
Published: February 2012

AbstractAxillary lymph node dissection (ALND) in breast cancer patients with positive sentinel nodes is under debate. We aimed to establish two models to predict non‐sentinel node (NSN) metastases in patients with micrometastases or isolated tumor cells (ITC) in sentinel nodes, to guide the decision for ALND. A total of 1,577 breast cancer patients with micrometastases and 304 with ITC in sentinel nodes, treated by sentinel lymph node dissection and ALND in 2002–2008 were identified in the Danish Breast Cancer Cooperative Group database. Risk of NSN metastases was calculated according to clinicopathological variables in a logistic regression analysis. We identified tumor size, proportion of positive sentinel nodes, lymphovascular invasion, hormone receptor status and location of tumor in upper lateral quadrant of the breast as risk factors for NSN metastases in patients with micrometastases. A model based on these risk factors identified 5% of patients with a risk of NSN metastases on nearly 40%. The model was however unable to identify a subgroup of patients with a very low risk of NSN metastases. Among patients with ITC, we identified tumor size, age and proportion of positive sentinel nodes as risk factors. A model based on these risk factors identified 32% of patients with risk of NSN metastases on only 2%. Omission of ALND would be acceptable in this group of patients. In contrast, ALND may still be beneficial in the subgroup of patients with micrometastases and a high risk of NSN metastases.
Wnt and BMP signals control intestinal adenoma cell fates
Authors: Farrall Alexandra L. , Riemer Pamela , Leushacke Marc , Sreekumar Amulya , Grimm Christina , Herrmann Bernhard G. , Morkel Markus 
Published: February 2012

AbstractCellular hierarchies and signals that govern stemness and differentiation of intestinal adenoma cells are not well defined. In this study, we used organotypic culture to investigate the impact of β‐catenin and BMP signals in cells that form intestinal adenoma in the mouse. We found that activation of β‐catenin signaling by loss of APC or transgenic induction of oncogenic mutant β‐catenin (Ctnnb1mut) initiates the conversion of untransformed intestinal cells to tumor cells. These tumor cells display cancer stem cell (CSC) traits such as increased expression of the CSC markers Cd133 and Cd44, a high capacity for self‐renewal and unlimited proliferative potential. Subsequent inactivation of transgenic Ctnnb1mut results in the reversion of tumor cells to normal intestinal stem cells, which immediately reinstall the cellular hierarchy of the normal intestinal epithelium. Our data demonstrate that oncogenic activation of β‐catenin signaling initiates the early steps of intestinal cellular transformation in the absence of irreversible genetic or epigenetic changes. Interestingly, we found that tumor cells in culture and in adenoma produce BMP4, which counteracts CSC‐like traits by initiating irreversible cellular differentiation and loss of self‐renewal capacity. We conclude that the opposition of stemness‐maintaining oncogenic β‐catenin signals and autocrine differentiating BMP signals within the adenoma cell provides a rationale for the formation of cellular hierarchies in intestinal adenoma and may serve to limit adenoma growth.
Student Award for Outstanding Research Winner in the Ph.D. Category for the 9th World Biomaterials Congress, Chengdu, China, June 1‐5, 2012
Authors: Mountziaris Paschalia M. , Tzouanas Stephanie N. , Mikos Antonios G. 
Published: February 2012

AbstractAs an initial step in the development of a bone tissue engineering strategy to rationally control inflammation, we investigated the interplay of bone‐like extracellular matrix (ECM) and varying doses of the inflammatory cytokine tumor necrosis factor alpha (TNF‐α) on osteogenically differentiating mesenchymal stem cells (MSCs) cultured in vitro on 3D poly(ε‐caprolactone) (PCL) microfiber scaffolds containing pregenerated bone‐like ECM. To generate the ECM, PCL scaffolds were seeded with MSCs and cultured in medium containing the typically required osteogenic supplement dexamethasone. However, since dexamethasone antagonizes TNF‐α, the interplay of ECM and TNF‐α was investigated by culturing naïve MSCs on the decellularized scaffolds in the absence of dexamethasone. MSCs cultured on ECM‐coated scaffolds continued to deposit mineralized matrix, a late stage marker of osteogenic differentiation. Mineralized matrix deposition was not adversely affected by exposure to TNF‐α for 4–8 days, but was significantly reduced after continuous exposure to TNF‐α over 16 days, which simulates the in vivo response, where brief TNF‐α signaling stimulates bone regeneration, while prolonged exposure has damaging effects. This underscores the exciting potential of PCL/ECM constructs as a more clinically realistic in vitro culture model to facilitate the design of new bone tissue engineering strategies that rationally control inflammation to promote regeneration. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2012.
Bioactivity and protein attachment onto bioactive glasses containing silver nanoparticles
Authors: Vulpoi A. , Gruian C. , Vanea E. , Baia L. , Simon S. , Steinhoff H.‐J. , Göller G. , Simon V. 
Published: February 2012

AbstractThere is much interest in silver containing glasses for use in bone replacement owing to the demonstrated antibacterial effect. In this work, 2 and 8 mol % of silver was added during the sol‐gel process to the composition of a bioactive glass belonging to CaO‐SiO2‐P2O5 system. The samples were characterized by means of ultraviolet‐visible spectroscopy and X‐ray photoelectron spectroscopy (XPS) techniques to demonstrate that the silver is embedded into the glass matrix as nanoparticles. Bioactivity test in simulated body fluid proved that the presence of silver in the bioactive glass composition, even in high amount, preserve or even improve the bioactivity of the starting glass, and consequently, leads to the carbonated apatite formation, which is the prerequisite for bioactive materials to bond with living bones. Complementary information proving these findings were delivered by performing X‐ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, energy dispersive spectroscopy, and XPS measurements. The presence of silver also improves protein binding capability to the bioactive glass surface as demonstrated by cw‐electron paramagnetic resonance experiments and XPS measurements. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A:, 2012.
Novel biodegradable three‐dimensional macroporous scaffold using aligned electrospun nanofibrous yarns for bone tissue engineering
Authors: Cai You‐Zhi , Zhang Guo‐Rong , Wang Lin‐Lin , Jiang Yang‐Zi , Ouyang Hong‐Wei , Zou Xiao‐Hui 
Published: February 2012

AbstractThis study aimed to develop a practical three‐dimensional (3D) macroporous scaffold from aligned electrospun nanofibrous yarns for bone tissue engineering. A novel 3D unwoven macroporous nanofibrous (MNF) scaffold was manufactured with electrospun poly(L‐lactic acid) and polycaprolactone (w/w 9:1) nanofibers through sequential yarns manufacture and honeycombing process at 65°C. The efficacy of 3D MNF scaffold for bone formation were evaluated using human embryonic stem cell‐derived mesenchymal stem cells (hESC‐MSCs) differentiation model and rabbit tibia bone defect model. In vitro, more cell proliferation and cell ingrowth were observed in 3D MNF scaffold. Moreover, calcium deposit was obviously detected in vitro differentiation of hESC‐MSCs. In vivo, histology and X‐ray showed that 3D MNF scaffold treated bone defect had fine 3D bony tissue formation around the scaffold as well as inside the scaffold at 3 weeks and 6 weeks. This study demonstrated that 3D MNF scaffold provides a structural support for hESC‐MSCs growth and guides bone formation suggesting that this novel strategy successfully makes use of electrospun fibers for bone tissue engineering, which may help realize the clinical translation of electrospun nanofibers for regenerative medicine in future. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A:, 2012.
Microparticles based on natural and synthetic polymers for ophthalmic applications
Authors: Tataru G. , Popa M. , Costin D. , Desbrieres J. 
Published: February 2012

AbstractSodium salt of carboxymethylcellulose/poly(vinyl alcohol) particles suitable for application in ocular drug administration were prepared by crosslinking with epichlorohydrin in an alkaline medium, in reverse emulsion. The influence of parameters related with the particles elaboration process (ratio between polymer mixture and crosslinking agent, concentration of polymer solution, duration of crosslinking reaction, stirring intensity, etc.) based on their composition, size, and swelling ability was studied. Obtained microparticles fulfill the requirements for biomaterials—they are formed from biocompatible polymers; the acute toxicity value (LD50) is high enough to consider these materials as weakly toxic (hence able to introduce within the organism); they are able to include and release drugs in a controlled way. The in vivo adrenalin ocular delivery from the microparticles was tested on voluntary human patient. The particles showed good adhesion properties without irritation to the patient and proved the capability to treat the ocular congestion. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A:, 2012.