bluuebunny/crossref_metadata_2025 huggingface dataset:
OmniPlex—a new QF‐PCR assay for prenatal diagnosis of common aneuploidies based on evaluation of the heterozygosity of short tandem repeat loci in the Czech population
Authors: Putzova Martina , Pecnova Lubomira , Dvorakova Lucie , Soldatova Inna , Goetz Petr , Stejskal David
Published: November 2008

Objectives

The aim of our study was to assess the utility of commonly used multiplex assays of short tandem repeat markers used for quantitative fluorescent polymerase chain reaction (QF‐PCR) for prenatal rapid aneuploidy detection (RAD) in routine prenatal diagnosis in the Czech population.

Methods

Two previously published RAD multiplexes (2M test) were tested on 2906 local prenatal samples and used to calculate the rates of heterozygosity within this population. Most of the markers used in both multiplexes were highly informative. However, some had little utility, either due to a low heterozygosity rate (D21S499, D18S978 and P39) or because they were difficult to evaluate (DXS1283E).

Results

After evaluation of the 2M test results, a new multiplex assay (OmniPlex) was designed, developed and tested on 960 samples. This new assay was evaluated for heterozygosity rates and for the probability of having two or more informative markers on each chromosome.

Conclusions

OmniPlex assay significantly improved the QF‐PCR methodology for rapid prenatal aneuploidy detection in the Czech population. Based on detected heterozygosity of markers used for QF‐PCR in this population, OmniPlex is a robust assay for the detection of chromosomes 13, 18, 21, X and Y in a single reaction. Copyright © 2008 John Wiley & Sons, Ltd.
Stem cell markers: Insights from membrane proteomics?
Authors: Ahn Sung‐Min , Goode Robert J. A. , Simpson Richard J.
Published: November 2008

Stem cells (SCs) are defined by their combined abilities to both self‐renew indefinitely in vitro and differentiate into adult cell types. One of the major driving forces of SC research is that SCs may provide a potentially unlimited source for cell‐replacement therapies in regenerative medicine. However, the identification of SCs and their progenies at different stages, and the success of cell‐replacement therapies, which form the basis of SC engineering, will depend on the ability to characterize and ultimately isolate homogeneous primary stem or progenitor cell populations to a large degree. Furthermore, the recent identification of cancer stem cells (CSCs) opens a new avenue for developing novel therapeutic strategies by targeting a specific subset of cancer cells with self‐renewal and proliferation capacity. Crucial to these tasks will be the discovery of novel plasma membrane‐associated SC markers. In this review, we focus on the seminal contribution that membrane proteomics could make to further clinical applications of SCs by providing tools for purification and identification of SCs and their progenies at each stage of differentiation, as well as, to understand the underlying mechanisms of SC differentiation. The need to standardize biological SC models before embarking on international SC proteomics efforts is discussed.
Proneurotensin/neuromedin N secreted from small cell lung carcinoma cell lines as a potential tumor marker
Authors: Ogura Shun‐ichiro , Kaneko Kumi , Miyajima Shoji , Ohshima Keiichi , Yamaguchi Ken , Mochizuki Tohru
Published: November 2008

Proteins secreted from specific cancer cells have a high potential for use as tumor markers. We identified secreted proteins produced by 15 different carcinoma cell lines grown in serum‐free medium using MS/MS. Proneurotensin/neuromedin N (proNT/NMN) was found in conditioned medium from four of seven small cell lung carcinoma cell lines but not from eight nonsmall cell lung carcinoma cell lines. These results indicate proNT/NMN has potential as a specific tumor marker of small cell lung carcinoma.
Proteome analysis of human foetal, aged and advanced nuclear cataract lenses
Authors: Hains Peter G. , Truscott Roger J. W.
Published: November 2008

The most complete proteome of human lenses has been compiled using 2‐D LC‐MS/MS analysis of foetal, aged normal and advanced nuclear cataract lenses. A total of 231 proteins were identified across all lens groups, including 112 proteins that have not been reported previously. Proteins were grouped according to their PANTHER molecular function classification in order to facilitate comparisons. Previously unreported N‐terminal acetylation was detected in a number of proteins, with the majority being associated with the prior removal of a methionine residue. This pattern of proteolysis may indicate that methionine aminopeptidase activity is present in human lenses. Acetylation is likely to aid in the stability of proteins that are present in the lens for many decades. Protein sequences were also used to interrogate the three human lens cDNA libraries publicly available. Surprisingly, 84 proteins we identified were not present in the cDNA libraries.
Her2 crosstalks with TrkA in a subset of prostate cancer cells: Rationale for a guided dual treatment
Authors: Festuccia Claudio , Gravina Giovanni Luca , Muzi Paola , Millimaggi Danilo , Dolo Vincenza , Vicentini Carlo , Ficorella Corrado , Ricevuto Enrico , Bologna Mauro
Published: November 2008

BACKGROUND

To date, no effective therapeutic treatment prevents prostate cancer (PCa) progression to more advanced and invasive disease forms. It has been demonstrated that the simultaneous high expression of p185HER2 and TrkA might confer a proliferative advantage to PCa cells.

METHODS

In this work we verified the crosstalk between TrkA and Her2 signaling pathways and the effects of a combined treatment with Her2 and TrkA inhibitors.

RESULTS

NGF induced TrkA activation and stimulated cell proliferation of PCa cells. NGF induced also tyrosine phosphorylation of p185HER2. This event was only partially inhibited by the pan Trk inhibitor, CEP‐701 but was strongly blocked by pertuzumab, a humanized antibody blocking Her2 heterodimerization. In presence of NGF, TrkA and Her2 co‐precipitated and this was dependent to the relative high cellular levels of TrkA since when cell lysates were immunoprecipitated with an antibody against Her2 the amount of TrkA were proportional to the cellular levels of this receptor. On the contrary when we immunoprecipitated using an antibody against TrkA the amount of Her2 seemed independent to cellular levels of Her2. So, combined treatment between CEP‐701 and pertuzumab showed supra‐additive effects in cells with higher levels of TrkA and Her2 suggesting once again that this was indicative of a higher response to treatment.

RESULTS

Our data suggest that the dual inhibition of TrkA and Her2 may be useful in a subset of patients in which TrkA and Her2 are overexpressed and in which the possibility of TrkA and Her2 protein‐binding is elevated. Prostate 69:337–345, 2009. © 2008 Wiley‐Liss, Inc.
Survival in surgically treated, nodal positive prostate cancer patients is predicted by histopathological characteristics of the primary tumor and its lymph node metastases
Authors: Fleischmann Achim , Schobinger Sylviane , Schumacher Martin , Thalmann George N. , Studer Urs E.
Published: November 2008

BACKGROUND

Histopathological risk factors for survival stratification of surgically treated nodal positive prostate cancer patients are poorly defined as reflected by only one category for nodal metastases.

METHODS

We evaluated biochemical recurrence‐free survival (RFS), disease‐specific survival (DSS), and overall survival (OS) in 102 nodal positive, hormone treatment‐naïve prostate cancer patients (median age: 65 years, range: 45–75 years; median follow‐up 7.7 years, range: 1.0–15.9 years) who underwent radical prostatectomy and standardized extended lymphadenectomy.

RESULTS

A significant stratification was possible, with the Gleason score of the primary and virtually all nodal parameters favoring patients with better differentiated primaries and metastases, lower nodal tumor burden, and without extranodal extension of metastases. In multivariate analyses, diameter of the largest metastasis (≤10 mm vs. >10 mm) was the strongest independent predictor for RFS (P < 0.001), DSS (P < 0.001), and OS (P < 0.001) with a more than quadrupled relative risk of cancer related deaths for patients with larger metastases (Hazard ratio: 4.2, Confidence interval: 2.0–8.9; 5‐year RFS/DSS/OS: 18%/57%/54%). The highest 5‐year survival rates were seen in patients with micrometastases only (RFS/DSS/OS: 47%/94%/94%).

CONCLUSION

The TNM classification's current allocation of only one category for nodal metastases in prostate cancers is unsatisfactory since subgroups with significantly different prognoses can be identified. The diameter of the patient's largest metastasis (≤10 mm vs. >10 mm) should be used for substaging because of its independent prognostic value. The substage “micrometastasis only” is also useful in nodal positive prostate cancer since it designates the subgroup with the most favorable outcome. Prostate 69:352–362, 2009. © 2008 Wiley‐Liss, Inc.
Spatially resolved Raman piezo‐spectroscopic stress analysis in CaMoO4 thin film grown on Si substrate
Authors: Li Runtao , Zhu Wenliang , Ge Wanyin , Pezzotti Giuseppe
Published: November 2008

Confocal piezo‐spectroscopy was applied to analyze the residual stress distribution developed in a CaMoO4‐film/Si‐substrate system, based on the spectroscopic shift upon stress of the 879 cm–1 Ag Raman mode of CaMoO4. In the stress characterization, use was made of spectral line scans, as well as laser defocusing measurements. A preliminary spectroscopic calibration of the Raman band was performed with using a ball‐on‐ring flexural bending jig. As a result, a value of –1.4 cm–1/GPa was found for the biaxial piezo‐spectroscopic coefficient of the Ag Raman mode of CaMoO4. A probe deconvolution procedure was introduced in the effort to correct the convoluting effect due to the finite size of the laser probe, taking advantage of the measurement of the probe response function. A theoretical analysis of the edge‐stress effect was then carried out and, accordingly, the actual in‐depth stress distribution was deduced from the observed spectral variation. Compressive residual stresses appeared on the CaMoO4 film side, while tensile residual stress occurred in the silicon substrate, and both stress magnitudes pronouncedly decreased with increasing distance from the interface. The results indicated relief in lattice mismatch in the epilayer, and such a relaxation mechanism was discussed in the paper. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The structural, morphological and magnetic characteristics of Mn‐implanted nonpolar a ‐plane GaN films
Authors: Sun Lili , Yan Fawang , Wang Junxi , Zeng Yiping , Wang Guohong , Li Jinmin
Published: November 2008

Dilute magnetic nonpolar GaN films have been fabricated by implanting Mn into unintentionally doped nonpolar a ‐plane GaN films at room temperature, and a subsequent rapid thermal annealing. The X‐ray diffraction analysis shows that after rapid thermal annealing the peak of the GaN X‐ray diffraction curve shifts to a lower angle, indicating a slight expansion of the GaN crystal lattice. Atomic force microscopy analysis shows that the annealing process does not change the morphology of the sample greatly. Magnetic property analysis indicates that the as‐annealed sample shows obvious ferromagnetic properties. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
High‐dielectric‐constant hafnium silicate insulator for low‐voltage pentacene field‐effect transistors
Authors: Yan Hu , Kagata Tsubasa , Arima Susumu , Sato Hiroshi , Okuzaki Hidenori
Published: November 2008

We prepared HfSiOx on a heavily doped n‐type silicon wafer by sputtering of a HfSi (50:50 at%) target using Ar:N2:O2 as carrier gas. The HfSiOx layer thus prepared was characterized by XPS, XRD, STEM and C –F measurements, indicating that the layer mainly consisted of 100 nm thick amorphous HfSiO5 with a dielectric constant ϵr = 7.7. The leakage current density was 1 nA/cm2 at an electric field of 2 MV/cm. We first fabricated top‐contact pentacene FETs using the high dielectric constant hafnium silicate as an insulator, coupled with a polymer microfiber‐based channel patterning technique. The pentacene FET showed well‐saturated output characteristics at low driving voltages, i.e. VD = –10 V and VG = –10 V, and hole mobility of 0.02 cm2/V s and on/off current ratio of 2600. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Scintillation properties of K2LaCl5:Ce microcrystals embedded in KCl host
Authors: Stryganyuk G. , Savchyn P. , Vistovskyy V. , Voloshinovskii A. , Antonyak O. , Birowosuto M. , Dorenbos P.
Published: November 2008

Scintillation properties under γ‐ray excitation and luminescence properties under X‐ray excitation of KCl with embedded K2LaCl5:Ce microphase crystals have been investigated. KCl–LaCl3(2 mol%)–CeCl3(0.1 mol% and 0.02 mol%) show scintillation yields of 15000–18000 photons/MeV with two decay time components of 300–420 ns and 1.2–1.9 µs. These properties compare with those of K2LaCl5:Ce bulk crystal. The luminescence study and scanning electron microscopy data indicate that the KCl–LaCl3–CeCl3 system contains K2LaCl5:Ce microcrystals of 10–50 μm size. The decrease of the intensity contribution and decay times of the slow component in the scintillation pulse of microcrystals compared with those in K2LaCl5:Ce single crystals are discussed. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Dielectric properties of highly c‐axis oriented chemical solution deposition derived SrBi4Ti4O15 thin films
Authors: Kambara Hiroyuki , Schneller Theodor , Sakabe Yukio , Waser Rainer
Published: November 2008

C‐axis oriented thin films of SrBi4Ti4O15 were prepared by a chemical solution deposition method. The influence of precursor chemistry and processing conditions on the resulting film morphology and the dielectric properties of SrBi4Ti4O15 thin films were investigated. By controlling the film formation process, highly c‐axis oriented SrBi4Ti4O15 thin films on (111)Pt/Si substrates were obtained at temperatures of 600 °C and 700 °C. The dielectric constant of the films is about 200 and it is independent of film thickness ranging from 55 to 160 nm. The dielectric constant also shows stable value with an increase in temperature from 25 °C to 200 °C. The leakage current of the film at 125 °C is in the order of 10–7 A/cm2 at an applied electric field of 500 kV/cm. These films exhibit stable dielectric constant and excellent insulating properties. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The structures, thermochemistry, and electron affinities of hydrogenated silicon clusters Si6Hn/Si6H (n = 3–14)
Authors: Li Xiao‐Jun , Li Chun‐Ping , Yang Ju‐Cai , Jalbout Abraham F.
Published: November 2008

The hydrogenated silicon clusters structures, electron affinities, and dissociation energies of the Si6Hn/Si6H (n = 3−14) species have been systematically investigated by means of three density functional theory (DFT) methods. The basis set used in this work is of double‐ζ plus polarization quality with additional diffuse s‐ and p‐type functions, denoted DZP++. The geometries are fully optimized with each DFT method independently. Three different types of energy separations presented in this work are the adiabatic electron affinity (EAad), the vertical electron affinity (EAvert), and the vertical detachment energy (VDE). The first SiH dissociation energies De (Si6Hn→ Si6Hn−1+H) for the neutral Si6Hn and De (Si6H→Si6H+H) for the anionic Si6H species have also been reported. © 2008 Wiley Periodicals, Inc. Int J Quantum Chem, 2009
Theoretical study on HBC− and HCB− anions using multiconfiguration second‐order perturbation theory
Authors: Li Wen‐Zuo , Cheng Jian‐Bo , Li Qing‐Zhong , Gong Bao‐An , Sun Jia‐Zhong
Published: November 2008

The HBC− and HCB− anions have been studied using the complete active space self‐consistent field, CASPT2, and DFT/B3LYP methods with the contracted atomic natural orbital (ANO) and cc‐pVTZ basis sets. The geometries of all stationary points along the potential energy surfaces were optimized at the CASSCF/ANO and B3LYP/cc‐pVTZ levels. The ground state of HBC− is predicted to be X2ϕ state, which is different from the previously published results. The CASPT2/ANO potential energy curves (PECs) of isomerization reactions were calculated as a function of HBC bond angle and the PECs also show the 2ϕ state is the ground state of HBC− anion. © 2008 Wiley Periodicals, Inc. Int J Quantum Chem, 2009
Theoretical studies on QSAR and mechanism of 2‐indolinone derivatives as tubulin inhibitors
Authors: Liao Si Yan , Qian Li , Miao Ti Fang , Lu Hai Liang , Zheng Kang Cheng
Published: November 2008

The theoretical studies on three‐dimensional quantitative structure activity relationship (3D‐QSAR) and action mechanism of a series of 2‐indolinone derivatives as tubulin inhibitors against human breast cancer cell line MDA‐MB‐231 have been carried out. The established 3D‐QSAR model from the comparative molecular field analysis (CoMFA) shows not only significant statistical quality but also predictive ability, with high correlation coefficient (R2 = 0.986) and cross‐validation coefficient (q2 = 0.683). In particular, the appropriate binding orientations and conformations of these 2‐indolinone derivatives interacting with tubulin are located by docking study, and it is very interesting to find that the plot of the energy scores of these compounds in DOCK versus the corresponding experimental pIC50 values exhibits a considerable linear correlation. Therefore, the inhibition mechanism that 2‐indolinone derivatives were regarded as tubulin inhibitors can be theoretically confirmed. Based on such an inhibition mechanism along with 3D‐QSAR results, some important factors improving the activities of these compounds were discussed in detail. These factors can be summarized as follows: the H atom adopted as substituent R1, the substituent R2 with higher electropositivity and smaller bulk, the substituents R4–R6 (on the phenyl ring) with higher electropositivity and larger bulk, and so on. These results can offer useful theoretical references for understanding the action mechanism, designing more potent inhibitors, and predicting their activities prior to synthesis. © 2008 Wiley Periodicals, Inc. Int J Quantum Chem, 2009
Gas‐phase pyrolysis mechanisms of 3‐anilino‐1‐propanol: Density functional theory study
Authors: Zhao Jing , Tang Ming‐Sheng , Wei Dong‐Hui , Zhao Chu‐Feng , Zhang Wen‐Jing , Wang Hong‐Ming
Published: November 2008

The gas‐phase pyrolytic decomposition mechanisms of 3‐anilino‐1‐propanol with the products of aniline, ethylene, and formaldehyde orN‐methyl aniline and aldehyde were studied by density functional theory. The geometries of the reactant, transition states, and intermediates were optimized at the B3LYP/6‐31G (d, p) level. Vibration analysis was carried out to confirm the transition state structures, and the intrinsic reaction coordinate method was performed to search the minimum energy path. Four possible reaction channels are shown, including two concerted reactions of direct pyrolytic decomposition and two indirect channels in which the reactant first becomes a ring‐like intermediate, followed by concerted pyrogenation. One of the concerted reactions in the direct pyrolytic decomposition has the lowest activation barrier among all the four channels, and so, it occurs more often than others. The results appear to be consistent with the experimental outcomes. © 2008 Wiley Periodicals, Inc. Int J Quantum Chem, 2009
Progressive changes in phytoplankton community structure in urbanized lowland river floodplains—a multivariate approach
Authors: Tabasum Tanveera , Trisal C. L.
Published: November 2008

Phytoplankton communities along the river Yamuna in Delhi stretch and its associated floodplain lakes showed considerable spatio‐temporal variations. Most of the species identified were cosmopolitan and typical of highly polluted rivers in tropical ecosystems. All the groups of phytoplankton with predominance of Cyanophyceae and some species of Chlorophyceae were distributed within the river stretch though with varying diversity and density. Relatively cleaner sites supported larger phytoplankton assemblages compared to those subjected to sewage outfalls and industrial effluents. Species elimination was observed mainly in the mid‐stretch and downstream of Okhla subjected to high loads of pollution. Co‐inertia analysis indicated significant co‐structures between water quality and species richness and density indicating water quality as the governing factor for phytoplankton distributions in the river stretch. Floodplain plays an important role in regenerating water quality thereby enhancing species richness and density. Floods play an important role in seasonal dynamics through dilution effects and promoting connectivity between river channel and floodplain lakes thereby facilitating species exchanges. Copyright © 2008 John Wiley & Sons, Ltd.
An ant colony optimization approach for reputation and quality‐of‐service‐based security in wireless sensor networks
Authors: Dhurandher Sanjay Kumar , Misra Sudip , Obaidat Mohammad S. , Gupta Nidhi
Published: November 2008

In wireless sensor networks (WSN), message security is an important concern. The protection of integrity and confidentiality of information and the protection from unauthorized access are important issues. However, due to factors such as resource limitations, absence of centralized access points, open wireless medium and small size of the sensor nodes, the implementation of security in WSN is a challenging task.

In this paper, we propose a protocol, quality‐based distance vector routing (QDV), for securing WSN using concepts based on Ant colony optimization ACO [1]. Two fundamental parameters—quality‐of‐service (QoS) and reputation [2]—are used. The high value of reputation of a node signifies that the node is trusted and is more reliable for data communication purposes. As a node shows signs of misbehavior, its reputation decreases, which, in turn, affects its quality‐of‐security QSec [2], thereby disabling the malicious nodes from gaining access to the network. By incorporating these two factors, we are able to distinguish the nodes present in the network. We, then, present a method to achieve “equilibrium” where the node is able to guarantee that its neighbors are secure. Copyright © 2008 John Wiley & Sons, Ltd.
An effective defensive node against jamming attacks in sensor networks
Authors: Mpitziopoulos Aristides , Gavalas Damianos
Published: November 2008

Jamming is defined as the act of intentionally directing electromagnetic energy towards a communication system to disrupt or prevent signal transmission. In the context of wireless sensor networks (WSNs), jamming is the type of attack which interferes with the radio frequencies used by sensor nodes and may be viewed as a special case of denial of service (DoS) attacks. Herein, we outline the possible jamming attacks a WSN may encounter. The main contribution of this paper is the outline of the design specifications of a prototype node ‘Ares’ that effectively defends jamming attacks. Our focus is on frequency hopping spread spectrum (FHSS) and direct sequence spread spectrum (DSSS), two of the most effective countermeasures against jamming. The main novel aspect of Ares is that it uses a hybrid FHSS–DSSS approach to defend jamming attacks. We suggest the use of a specific FHSS technique in 5 GHz band with 51 frequency channels wherein the channel sequence is generated using a key (which derives from a secret word), known only to the sink and the sensor nodes, as a seed. Each channel uses DSSS modulation with 16‐bit pseudo noise (PN) code. The PN code derives from the same key used for FHSS channel generation. The pre‐eminence of our method against alternative anti‐jamming techniques is demonstrated through extensive simulation tests. Copyright © 2008 John Wiley & Sons, Ltd.
Bayesian propensity score analysis for observational data
Authors: McCandless Lawrence C. , Gustafson Paul , Austin Peter C.
Published: November 2008

In the analysis of observational data, stratifying patients on the estimated propensity scores reduces confounding from measured variables. Confidence intervals for the treatment effect are typically calculated without acknowledging uncertainty in the estimated propensity scores, and intuitively this may yield inferences, which are falsely precise. In this paper, we describe a Bayesian method that models the propensity score as a latent variable. We consider observational studies with a dichotomous treatment, dichotomous outcome, and measured confounders where the log odds ratio is the measure of effect. Markov chain Monte Carlo is used for posterior simulation. We study the impact of modelling uncertainty in the propensity scores in a case study investigating the effect of statin therapy on mortality in Ontario patients discharged from hospital following acute myocardial infarction. Our analysis reveals that the Bayesian credible interval for the treatment effect is 10 per cent wider compared with a conventional propensity score analysis. Using simulations, we show that when the association between treatment and confounders is weak, then this increases uncertainty in the estimated propensity scores. Bayesian interval estimates for the treatment effect are longer on average, though there is little improvement in coverage probability. A novel feature of the proposed method is that it fits models for the treatment and outcome simultaneously rather than one at a time. The method uses the outcome variable to inform the fit of the propensity model. We explore the performance of the estimated propensity scores using cross‐validation. Copyright © 2008 John Wiley & Sons, Ltd.
Proof of concept and dose estimation with binary responses under model uncertainty
Authors: Klingenberg B.
Published: November 2008

This article suggests a unified framework for testing Proof of Concept (PoC) and estimating a target dose for the benefit of a more comprehensive, robust and powerful analysis in phase II or similar clinical trials. From a pre‐specified set of candidate models, we choose the ones that best describe the observed dose–response. To decide which models, if any, significantly pick up a dose effect, we construct the permutation distribution of the minimum P‐value over the candidate set. This allows us to find critical values and multiplicity adjusted P‐values that control the familywise error rate of declaring any spurious effect in the candidate set as significant. Model averaging is then used to estimate a target dose. Popular single or multiple contrast tests for PoC, such as the Cochran–Armitage, Dunnett or Williams tests, are only optimal for specific dose–response shapes and do not provide target dose estimates with confidence limits. A thorough evaluation and comparison of our approach to these tests reveal that its power is as good or better in detecting a dose–response under various shapes with many more additional benefits: It incorporates model uncertainty in PoC decisions and target dose estimation, yields confidence intervals for target dose estimates and extends to more complicated data structures. We illustrate our method with the analysis of a Phase II clinical trial. Copyright © 2008 John Wiley & Sons, Ltd.
Robust outbreak surveillance of epidemics in Sweden
Authors: Frisén M. , Andersson E. , Schiöler L.
Published: November 2008

Outbreak detection is of interest in connection with several diseases and syndromes. The aim is to detect the progressive increase in the incidence as soon as possible after the onset of the outbreak. A semiparametric method is applied to Swedish data on tularaemia and influenza. The method is constructed to detect a change from a constant level to a monotonically increasing incidence. If seasonal effects are present, the residuals from a model incorporating these can be used. The properties of the method are evaluated by application to Swedish data on tularaemia and influenza and by simulations. The suggested method is compared with subjective judgments as well as with other algorithms. The conclusion is that the method works well. A user‐friendly computer program is described. Copyright © 2008 John Wiley & Sons, Ltd.
Principles of complex systems for systems engineering
Authors: Sheard Sarah A , Mostashari Ali
Published: November 2008

This paper shows how three systems of types well known to systems engineers can be understood as complex systems. This is important because research in complex systems sciences is vibrant and provides critical insight, but if systems engineers do not understand the complex aspects of the systems they work with daily, they may not be able to use these research results. To date, systems engineering has been looking only at exploiting the “order” side of the order‐to‐chaos spectrum, and it is time now to understand and begin to utilize principles from the middle and from the chaos side of the spectrum. Three complex systems examples are INCOSE, the systems engineering process (such as a company's standard process), and air traffic control. INCOSE represents most volunteer organizations and social groups. Most systems engineers do not realize that the systems engineering process for a company is a network that can be studied by complex systems methods. Air traffic control may come closest to many systems engineers' definition of a system. This paper provides principles of complex systems based on a variety of sources, and shows the application of complex systems to one of the examples. © 2008 Wiley Periodicals, Inc. Syst Eng
Prognostic Factors After Resection of Pancreatic Cancer
Authors: Ueda Michio , Endo Itaru , Nakashima Masayuki , Minami Yuta , Takeda Kazuhisa , Matsuo Kenichi , Nagano Yasuhiko , Tanaka Kuniya , Ichikawa Yasushi , Togo Shinji , Kunisaki Chikara , Shimada Hiroshi
Published: November 2008

Objectives

The purpose of this study was to identify important prognostic factors related to the status of a pancreatic tumor, its treatment, and the patient’s general condition.

Methods

Between April 1992 and December 2006, 140 patients underwent a pancreatic resection for invasive ductal carcinoma. Prognostic factors were defined by univariate and multivariate analyses.

Results

The study included 103 tumors in the head of the pancreas and 37 tumors in the body or tail. The median survival time and the actuarial 5‐year survival rate for all patients were 14.5 months and 12.3%, respectively. Using the significant prognostic factors identified by univariate analysis, multivariate analysis revealed that a preoperative serum CA19‐9 concentration >100 U/ml (HR = 1.84, p = 0.0074), a tumor size >3 cm (HR = 1.74, p = 0.0235), venous involvement (HR = 2.39, p = 0.0006), a transfusion requirement of ≥1000 ml (HR = 2.23, p = 0.0006), and a serum albumin concentration on 1 postoperative month (1POM) < 3 g/dl (HR = 2.40, p = 0.0009) were significant adverse prognostic factors. The presence of hypoalbuminemia on 1POM significantly correlated with a longer surgical procedure (p = 0.0041), extended nerve plexus resection around the superior mesenteric artery (p = 0.0456), and a longer postoperative hospital stay (p = 0.0063).

Conclusion

To improve long‐term survival, preserving the patient’s general condition by performing a curative resection with a short operation time and minimal blood loss should be the most important principle in the surgical treatment of pancreatic cancer.
From Molecular Fossils of Bacterial Hopanoids to the Formation of Isoprene Units: Discovery and Elucidation of the Methylerythritol Phosphate Pathway
Authors: Rohmer Michel
Published: November 2008

Investigations on the biosynthesis of bacterial triterpenoids of the hopane series led to the unexpected discovery of an alternative mevalonate independent pathway for the formation of isoprene units. Methylerythritol phosphate, already presenting the C5 branched isoprene skeleton, is the key intermediate. This pathway was independently characterized in ginkgo embryos for the formation of diterpenoids. It is present in most bacteria and in the plastids of all organisms belonging to phototrophic phyla. The key steps of the discovery and elucidation of this metabolic route are presented in this review.
Implementation of Transition Programs can Prevent Another Lost Generation of Patients with Congenital Heart Disease
Authors: Moons Philip , Hilderson Deborah , Van Deyk Kristien
Published: November 2008

Congenital heart disease is the most frequently occurring birth defect. To date, more than 90% of the children born with a heart defect reach adulthood. Since many patients are prone to residua and sequelae, lifelong specialized care is required. However, studies indicate that about one-half to three-quarters of the patients are lost to follow-up when they have grown up. This has resulted in a virtual lost generation. Lapse of care is associated with significant morbidity. Therefore, implementation of strategies to prevent patients from failing to continue regular follow-up is critical. It is argued that transition programs that inform patients about the rationale for ongoing follow-up and that teach them how to navigate the medical system can avoid another lost generation.
The (not always sweet) uses of opportunism: Post-communist political parties in Poland
Authors: Jasiewicz Krzysztof
Published: November 2008

The author argues that political opportunism, an attitude common among communist party members before 1989, turned into both the blessing and the curse for post-communist parties in Poland. Once hopeful of secure careers in the authoritarian structures of the old regime, after the regime breakdown communists found themselves in a situation where the only chance for such a career could be associated with the party reinventing itself as a player in the field of pluralist democracy. Opportunistic attitudes of communist apparatchiks and nomenklatura members were instrumental in transforming them, individually and collectively, into effective actors in market economy and competitive politics. Yet the same attitudes doomed the post-communists once the opportunities associated with access to political power opened up widely. The same people who in the 1990s were so apt in turning the rules of democratic game into their collective advantage, in the 2000s acted with a sense of impunity and lack of any consideration for political accountability that in democracies arrives at the end of any election cycle. Plagued by corruption scandals, they lost their popular base: the economically disadvantaged groups to nationalistic populists, the urbane libertarians to liberal democrats.
Discursive Representation
Authors: DRYZEK JOHN S. , NIEMEYER SIMON
Published: November 2008

Democracy can entail the representation of discourses as well as persons or groups. We explain and advocate discursive representation; explore its justifications, advantages, and problems; and show how it can be accomplished in practice. This practice can involve the selection of discursive representatives to a formal Chamber of Discourses and more informal processes grounded in the broader public sphere. Discursive representation supports many aspects of deliberative democracy and is especially applicable to settings such as the international system lacking a well-defined demos.
Punishment, Property, and the Limits of Altruism: Locke's International Asymmetry
Authors: TUCKNESS ALEX
Published: November 2008

The standard interpretation of Locke assumes symmetry between punishment by individuals in the state of nature and punishment by states in the state of nature. The standard interpretation is incorrect because in cases where the punishment is altruistic, the state is not the functional equivalent of a person, having a more restricted power to punish. The asymmetry arises from Locke's contractualism because individuals in the state of nature might reasonably refuse to give governments the power to punish altruistically. This interpretation clarifies some ongoing puzzles about Locke's theory of property where questions about coerced sacrifices to benefit others also arise. Locke's argument is vulnerable to important objections, specifically that he equivocates on the meaning of the word “body,” that he places too much emphasis on the right of self-preservation, and that he legitimates nearly unlimited appropriation by states.
The antioxidant effects of quercetin metabolites on the prevention of high glucose-induced apoptosis of human umbilical vein endothelial cells
Authors: Chao Chia-Lun , Hou Yu-Chi , Lee Chao Pei-Dawn , Weng Ching-Sung , Ho Feng-Ming
Published: November 2008

Diabetes mellitus is an important risk factor for CVD. A previous study showed that high glucose induced the apoptosis of human umbilical vein endothelial cells (HUVEC) via the sequential activation of reactive oxygen species, Jun N-terminal kinase (JNK) and caspase-3. The apoptosis cascade could be blocked by ascorbic acid at the micromolar concentration (100 μm). In addition to ascorbic acid, quercetin, the most abundant dietary flavonol, has been recently actively studied in vascular protection effects due to its antioxidant effect at low micromolar concentrations (10–50 μm). Quercetin sulfate/glucuronide, the metabolite of quercetin in blood, however, has been rarely evaluated. In the present study, we investigated the effect of quercetin sulfate/glucuronide on the prevention of high glucose-induced apoptosis of HUVEC. HUVEC were treated with media containing high glucose (33 mm) in the presence or absence of ascorbic acid (100 μm) or quercetin sulfate/glucuronide (100 nm, 300 nm and 1 μm). For the detection of apoptosis, a cell death detection ELISA assay was used. The level of intracellular H2O2 was measured by flow cytometry. JNK and caspase-3 were evaluated by a kinase activity assay and Western blot analysis. The results showed that high glucose-induced apoptosis was inhibited by quercetin sulfate/glucuronide in a dose-dependent manner. The effect of quercetin sulfate/glucuronide on H2O2 quenching, inhibition of JNK and caspase-3 activity at the nanomolar concentration (300 nm) was similar to that of ascorbic acid at the micromolar concentration (100 μm). The findings of the present study may shed light on the pharmacological application of quercetin in CVD.
A Joint Preface
Authors: Betts Paul , Ledford Ken , Umbach Maiken
Published: November 2008

All nation-states are creations of physical topography, historical circumstance, political claims, and cultural imagination. A country's identity may be the result of its material place, legal self-understanding, and (invented) national traditions, but it is also defined by certain founding myths and historical associations born of dreams and distance. The histories of the United States, Liberia, and Israel are obvious examples, in that their territories have become mythic “landscapes of memory” in their own right for many around the world, even among those who have never been there.
The Myth of Chancellor von Schleicher's Querfront Strategy
Authors: Turner Henry Ashby
Published: November 2008

In the multitudinous accounts of Adolf Hitler's rise to power, one interpretation dominates with regard to the political strategy of his predecessor as Reich chancellor, General Kurt von Schleicher. Beginning with the pioneering books of the journalist Konrad Heiden in the 1930s and continuing through countless versions down to the most recent scholarly works, Schleicher has, with rare exceptions, been depicted as having sought to thwart Hitler by bringing behind his own cabinet a political bloc extending from a left wing split away from the Nazi Party to trade union elements of the republican Social Democratic Party. Sometimes described as a Gewerkschaftsachse, this putative goal on the part of Schleicher has now usually come to be referred to as his Querfront strategy. Long regarded by most historians as axiomatic, that version of the chancellor's intentions has seldom been subjected to critical analysis. It is, however, fundamentally erroneous and serves to obscure his actually very different aims.
Dynamics of bubbles near a rigid surface subjected to a lithotripter shock wave. Part 2. Reflected shock intensifies non-spherical cavitation collapse
Authors: CALVISI M. L. , ILORETA J. I. , SZERI A. J.
Published: November 2008

In this paper we use the boundary integral method to model the non-spherical collapse of bubbles excited by lithotripter shock waves near a rigid boundary. The waves we consider are representative of those developed by shock wave lithotripsy or shock wave therapy devices, and the rigid boundaries we consider are representative of kidney stones and reflective bony tissue. This study differs from previous studies in that we account for the reflection of the incident wave and also the asymmetry of the collapse caused by the presence of the rigid surface. The presence of the boundary causes interference between reflected and incident waves. Quantities such as kinetic energy, Kelvin impulse and centroid translation are calculated in order to illuminate the physics of the collapse process. The main finding is that the dynamics of the bubble collapse depend strongly on the distance of the bubble relative to the wall when reflection is taken into account, but much less so when reflection is omitted from the model. The reflection enhances the expansion and subsequent collapse of bubbles located near the boundary owing to constructive interference between incident and reflected waves; however, further from the boundary, the dynamics of collapse are suppressed owing to destructive interference of these two waves. This result holds regardless of the initial radius of the bubble or its initial state at the time of impact with the lithotripter shock wave. Also, the work done by the lithotripter shock wave on the bubble is shown to predict strongly the maximum bubble volume regardless of the standoff distance and the presence or absence of reflection; furthermore, allowing for non-sphericity, these predictions match almost exactly those of a previously developed spherical model.
Dynamics of bubbles near a rigid surface subjected to a lithotripter shock wave. Part 1. Consequences of interference between incident and reflected waves
Authors: ILORETA J. I. , FUNG N. M. , SZERI A. J.
Published: November 2008

In this paper we consider the dynamics of bubbles near a kidney stone subjected to a lithotripter shock wave. We address the effect of kidney stone geometry and composition on the cavitation potential near the stone in a shock wave lithotripter. The analysis is based on the previously developed work metric in which the work done on a bubble by the lithotripter shock wave (LSW) is used to determine the maximum radius the bubble achieves. Results of the reflection of the LSW from cylindrical kidney stones with proximal surfaces of varying geometry show that the presence of the stone enhances bubble growth near the stone and decreases growth further away, owing to constructive and destructive interference, respectively. These effects hold true regardless of the shape and curvature of the face, and are strongest for stones with concave faces and higher reflection coefficients. A consequence of the analysis is an elucidation of the mechanism for enhanced cavitation activity and creation of deep craters on the proximal side of a kidney stone, as have been observed in recent experiments.
Modelling of cavitation in diesel injector nozzles
Authors: GIANNADAKIS E. , GAVAISES M. , ARCOUMANIS C.
Published: November 2008

A computational fluid dynamics cavitation model based on the Eulerian–Lagrangian approach and suitable for hole-type diesel injector nozzles is presented and discussed. The model accounts for a number of primary physical processes pertinent to cavitation bubbles, which are integrated into the stochastic framework of the model. Its predictive capability has been assessed through comparison of the calculated onset and development of cavitation inside diesel nozzle holes against experimental data obtained in real-size and enlarged models of single- and multi-hole nozzles. For the real-size nozzle geometry, high-speed cavitation images obtained under realistic injection pressures are compared against model predictions, whereas for the large-scale nozzle, validation data include images from a charge-coupled device (CCD) camera, computed tomography (CT) measurements of the liquid volume fraction and laser Doppler velocimetry (LDV) measurements of the liquid mean and root mean square (r.m.s.) velocities at different cavitation numbers (CN) and two needle lifts, corresponding to different cavitation regimes inside the injection hole. Overall, and on the basis of this validation exercise, it can be argued that cavitation modelling has reached a stage of maturity, where it can usefully identify many of the cavitation structures present in internal nozzle flows and their dependence on nozzle design and flow conditions.
Experiments on standing bubbles in a vertical pipe
Authors: IOIO GENNARO DELLO , WOODS ANDREW W.
Published: November 2008

We present a series of laboratory experiments in which a steady stream of air is supplied through a small hole in the wall of a vertical pipe of rectangular cross-section down which there is a steady flux of water. For a range of liquid flow rates, the air forms a steady standing bubble whose nose is attached to the point of air supply. The steady bubble sheds a flux of much smaller air bubbles at its base, located downstream of the air injection point. The minimum liquid speed for which steady standing bubbles develop occurs at a particular Froude number of the liquid flow, Frd = U/$/sqrt{\it gd}$ = 0.38, where U is the upstream speed, g the acceleration due to gravity and d the width of the cell. These trapped bubbles are distinct from the freely rising Taylor bubble, in that the Froude number at the nose is variable. Also, on a length scale greater than that influenced by surface tension, we find that the bubble nose asymptotes to a cusp-like shape, with an angle that decreases with Frd. We show that numerical solutions of the potential flow equations replicate the bubble shape and angle of the cusp, which appear independent of the gas flux. We also find that there is a minimum gas flux for which these standing bubbles develop. As the gas flux decreases below this threshold, the standing bubbles become unstable and, instead, a much shorter oscillating bubble develops. This produces a wake which has similarities with that formed downstream of a cylinder in a confined channel, but which also carries bubbles downstream. We also find that with sufficiently small gas flux, no bubble develops. For liquid flow rates smaller than the critical value, Frd < 0.38, we find that the bubbles become unstable and detach from the injection point and rise up the tube.
Energy balances for axisymmetric gravity currents in homogeneous and linearly stratified ambients
Authors: UNGARISH MARIUS , HUPPERT HERBERT E.
Published: November 2008

We analyse the exchange of energy for an axisymmetric gravity current, released instantaneously from a lock, propagating over a horizontal boundary at high Reynolds number. The study is relevant to flow in either a wedge or a full circular geometry. Attention is focused on effects due to a linear stratification in the ambient. The investigation uses both a one-layer shallow-water model and Navier–Stokes finite-difference simulations. There is fair agreement between these two approaches for the energy changes of the dense fluid (the current). The stratification enhances the accumulation of potential energy in the ambient and reduces the energy decay (dissipation) of the two-fluid system. The total energy of the axisymmetric current decays considerably faster with distance of propagation than for the two-dimensional counterpart.