bluuebunny/crossref_metadata_2025 huggingface dataset:
Mechanical resolution of chiral objects in achiral media: Where is the size limit?
Authors: Tencer Michal , Bielski Roman
Published: August 2010

Macroscopic chiral objects (boats and planes with turned rudders, shoes, etc.) get separated from their mirror‐image counterparts by motion in achiral media. However, chiral molecules are not enantio‐differentiated without the presence of a chiral environment, which may be due to other chiral molecules in the medium. This article explores the reasons of this micro/macro difference as well as the size borderline between the two regimes. There are two major demarcation lines, both related to the object's chaotic thermal motion. The first one is due to destruction of the necessary spatial orientation by the fast rotational diffusion. Only particles larger than 1 μm can maintain their original orientation for 1 sec or longer. For smaller particles, an additional external orienting factor, e.g., a strong electric field has to be applied. The second limitation is defined by the ratio of the hydrodynamic separation of the enantiomers (which is directly proportional to time) to their displacement due to the translational Brownian motion (which is proportional to square root of time). On the laboratory time scales (up to a year), the chiral objects have to be larger than 0.25 μm to be resolved. On evolutionary time scales, much smaller object could be resolved. For enantiomers approaching the molecular size, periods comparable to the age of the universe would be required. Chirality, 2011. © 2010 Wiley‐Liss, Inc.
A lab‐scale reaction calorimeter for olefin polymerization
Authors: Tisse Virginie F. , Sheibat‐Othman Nida , McKenna Timothy F. L.
Published: August 2010

A reaction calorimeter was built to follow slurry‐phase polymerizations of ethylene using different types of supported catalysts. It was shown that heat flow calorimetry, employing a high‐gain observer for the evaluation of the initial conditions was an extremely useful tool for the measurement of on‐line reaction rates, and a study of the influence of different parameters such as the stirring rate or solid content in real time. It was shown that if one uses solid contents under 30% (volume) then it is not necessary to account for the influence of this quantity on the overall heat transfer coefficient.

Un calorimètre de réaction a été construit pour le suivi des polymérisations des phases de suspension de l'éthylène utilisant différents types de catalyseurs adaptés. Il a été démontré que la calorimétrie du flux thermique, utilisant un observateur à gain élevé pour l'évaluation des conditions initiales s'est avérée un outil extrêmement utile pour mesurer les taux de réaction en ligne, et pour l'étude en temps réel de l'influence de différents paramètres tels que la vitesse d'agitation ou le contenu en matière solide. Il a été démontré que si l'on utilise la matière solide en dessous de 30% (en termes de volume), alors il n'est pas nécessaire de prendre en compte l'influence de cette quantité sur le coefficient global de transfert thermique. Can. J. Chem. Eng. © 2010 Canadian Society for Chemical Engineering
Mass transfer and mixing characteristics in an airlift‐driven fibrous‐bed bioreactor
Authors: Kilonzo Peter M. , Margaritis Argyrios , Bergougnou Maurice A.
Published: August 2010

An internal loop airlift‐driven fibrous bed bioreactor (ILALFBB) was designed and developed with a high degree of flexibility to handle genetically engineered and fragile shear‐sensitive cells. The mixing and oxygen mass transfer characteristics have been investigated. A cotton fibre was set in the downcomer of the ILALB to represent the fibrous packed bed and the outcome results were compared with those of the polyurethane foam (PUF) packed and unpacked ILALB systems. The effects of fibre, packing height, bed top and bottom clearances, spacing between adjacent fibre surfaces, and superficial gas velocity were investigated. The liquid phase mixing output variables included the liquid circulation velocity (ULc), circulation time (tLc), mixing time (tLm), Bodenstein number (BoL), and axial dispersion coefficient (EL), whereas the mass transfer out variable was the KLa. BoL and EL in the riser and downcomer regions of all packed systems increased with increasing in packing height, packing top clearance, and superficial gas velocity, except the overall BoL was independent of gas velocity at low gas velocities. The BoL was found highest in the riser of the large cotton and small PUF packed system with large spacing and the EL in the downcomer of PUF packed systems with smaller spacing between fibre surfaces. Increased amounts of packing in the ILALB, whether in the form of cotton or PUF decreased the ULc in the bioreactor because of the increased frictional resistance and tortuosity. The reduction in ULc was significant for large packing with smaller spacing between fibre surfaces and increased bottom clearances of the cotton packed system. High circulation times (tLc) and shorter mixing times (tLm) were achieved using small PUF packing with large top clearance. Relatively high KLa values were obtained using large packing with large top clearances and spacing between fibre surfaces. The boost in KLa was associated with increased gas holdup and/or interfacial area, due to bubble breakage by the shearing action of the fibrous‐bed. Empirical correlation proposed for EL, BoL, and KLa gave a good fit of the experimental data.
MeOH to DME in bubbling fluidized bed: Experimental and modelling
Authors: Kaarsholm Mads , Joensen Finn , Cenni Roberta , Chaouki Jamal , Patience Gregory S.
Published: August 2010

Methanol dehydration over a ZSM‐5 containing catalyst was studied in a fluidized bed reactor. At temperatures ranging from 250 to 325°C, methanol conversion varied from 30% at a contact times of 0.14 s and approached 100% of the equilibrium conversion at a contact time starting from 10 s. Sequential and parallel reactions were negligible at low temperatures while hydrocarbon formation became appreciable at 325°C. Online gas analysis by mass spectrometry provided real‐time measurements at a frequency of 4.4 Hz that allowed for fast determination of steady‐state conditions. Gas phase residence time distribution (RTD) measurements indicated that axial dispersion was essentially negligible at short contact times with a shallow bed of catalyst. With longer residence times, the flow pattern could be approximated by six continuously stirred‐tank reactors (CSTR) in series. Both the simple 1D hydrodynamic model and a detailed multi‐zone fluidized model were used to interpret the experimental data to derive a kinetic expression for the dehydration of methanol to di‐methyl ether (DME). The expression includes the reverse reaction that is most often neglected in the literature. The reaction data were best fit with the kinetics based on the 1D model. The fluidized bed is a viable reactor type for kinetic measurements of highly exothermic reactions where hotspots and radial and axial temperature gradients are problematic in fixed beds.
Determination of Cyanuric Acid in Swimming Pool Water and Milk by Differential Pulse Polarography
Authors: Yilmaz Ümmihan T. , Yazar Zehra
Published: August 2010

Cyanuric acid is a suspected gastrointestinal or liver toxicant in humans. Therefore, determination of trace cyanuric acid is very important, in this work a novel, sensitive, and reliable method was developed using differential pulse polarography. Optimum conditions for analytical determination were found to be at a pH of 9.5, Britton–Robinson at a reduction potential of −105 mV. Experimental results indicate an excellent linear correlation between the peak current and the concentration in the range of cyanuric acid from 0.5 to 27.0 µM (0.06–3.5 µg mL−1) with a correlation coefficient of 0.997. The limit of detection and limit of quantification were obtained as 0.15 and 0.5 µM (0.02–0.06 µg mL−1), respectively. The proposed method was successfully applied to the determination of cyanuric acid in pool water and in spiked milk. Cyanuric acid level in swimming pool water was found as 2.54 ± 0.47 µg mL−1 (19.7 ± 2.29 µM) in swimming pool water for N = 4 and 95% confidence interval. The recoveries were found to be sufficient. Also, the standard deviation of the data was low which shows high accuracy and precision of proposed differential pulse polarographic method. The influences of some other commonly found inorganic salts on the determination of cyanuric acid were also examined. Some interfering species were eliminated using complexing agents, e.g., EDTA.
Synthesis and Evaluation of Bombesin Analogues Conjugated to Two Different Triazolyl‐Derived Chelators for 99mTc Labeling
Authors: Brans Luc , García‐Garayoa Elisa , Schweinsberg Christian , Maes Veronique , Struthers Harriet , Schibli Roger , Tourwé Dirk
Published: August 2010

Overexpression of the gastrin‐releasing peptide receptor (GRPR) in a variety of human carcinomas has provided a means of diagnosis and treatment. Previously we reported a metabolically stable (NαHis)Ac‐βAla‐βAla‐[Cha13,Nle14]BBS(7–14) analogue with high affinity for the GRPR. We have also shown that the biodistribution pattern of this fairly lipophilic, radiolabeled peptide can be enhanced by glycation, which is easily carried out by CuI‐catalyzed cycloaddition. Herein, we further elaborate this “click approach” in the synthesis of a new series of triazole‐based chelating systems as alternatives to the (NαHis)Ac chelator for labeling with the 99mTc(CO)3 core. The bombesin analogues, containing these new chelating systems, were evaluated with regard to their synthesis and in vitro and in vivo properties, and were compared with their (NαHis)Ac counterparts. The influence of the chelator on biodistribution properties was less than that of glycation, which clearly improved the tumor‐to‐background ratios.
Effects of complementary therapies on clinical outcomes in patients being treated with radiation therapy for prostate cancer
Authors: Beard Clair , Stason William B. , Wang Qian , Manola Judith , Dean‐Clower Elizabeth , Dusek Jeffery A. , DeCristofaro Susan , Webster Ann , Doherty‐Gilman Anne M. , Rosenthal David S. , Benson Herbert
Published: August 2010

BACKGROUND.

This pilot randomized controlled trial (RCT) examined the clinical effects of 2 complementary (CAM) therapies, relaxation response therapy (RRT) and Reiki therapy, in men being treated with external beam radiotherapy (EBRx) for prostate cancer.

METHODS.

Study participants were randomly assigned to weekly RRT, Reiki therapy twice weekly, or wait‐list control. Well‐validated instruments measured anxiety (STAI), depression (CES‐D), and quality of life in cancer patients (FACT‐G) at randomization and 3 subsequent time points.

RESULTS.

Fifty‐four men were randomized, and 16 of 18 (89%) of RRT and 15 of 18 (83%) of Reiki patients completed the intervention protocol. No statistically significant difference was found between the RRT, Reiki, and control groups on total scores for the STAI, CES‐D, or FACT‐G instruments at any time point. However, at the end of the intervention, significant improvement was found on the emotional well‐being subscale of the FACT‐G quality of life scale in the RRT group compared with the Reiki and control groups (P = .01). In participants who were classified as “anxious” at baseline, statistically significant improvement occurred in the RRT group (P = .02), and a positive trend was found in the Reiki group (P = .10).

CONCLUSIONS.

This pilot study documented the feasibility of conducting a RCT of CAM therapies in men undergoing EBRx for prostate cancer. Relaxation response therapy improved emotional well being and eased anxiety in participants. Reiki therapy also had a positive effect in anxious patients. A larger study to verify and better define the benefits of these therapies in men with prostate cancer is warranted. Cancer 2011. © 2010 American Cancer Society.
Policy implications of early onset breast cancer among Mexican‐origin women
Authors: Miranda Patricia Y. , Wilkinson Anna V. , Etzel Carol J. , Zhou Renke , Jones Lovell A. , Thompson Patricia , Bondy Melissa L.
Published: August 2010

BACKGROUND:

Overall, Latinas are more likely to be diagnosed with a more advanced stage of breast cancer and are 20% more likely to die of breast cancer than non‐Hispanic white women. It is estimated that from 2003 to 2006, $82.0 billion in direct medical care expenditures, in addition to 100,000 lives annually, could be saved by eliminating health disparities experienced by Latinos and increasing the use of up to 5 preventive services in the United States. An additional 3700 lives could be saved if 90% of women aged ≥40 years were recently screened for breast cancer.

METHODS:

The authors examined the risk for breast cancer in a case‐control, population‐based sample of Mexican‐origin women in Harris County, Texas (n = 714), where the rates of breast cancer mortality for Latina women have doubled since 1990.

RESULTS:

Half of breast cancer cases (n = 119) were diagnosed in women aged <50 years. In a multivariate model, women who had a family history of breast cancer (odds ratio [OR], 4.3), who were born in Mexico and had high levels of language acculturation (OR, 2.5), and who did not have health insurance (OR, 1.6) had the highest risk for breast cancer.

CONCLUSIONS:

Because the current results indicated that Mexican‐origin women are at high‐risk for early onset, premenopausal breast cancer, the authors recommended policies that target screening, education, and treatment to prevent increased disparities in mortality. The authors concluded that the inclusion of community members and policymakers as partners in these endeavors would further safeguard against an increase in cancer health disparities and aid in formulating a policy agenda congruent with scientifically based, community‐driven policy efforts that address breast cancer screening, education, and treatment in this vulnerable population. Cancer 2011. © 2010 American Cancer Society.
Elevated expression of CXC chemokines in pediatric osteosarcoma patients
Authors: Li Yiting , Flores Ricardo , Yu Alexander , Okcu M. Fatih , Murray Jeffrey , Chintagumpala Murali , Hicks John , Lau Ching C. , Man Tsz‐Kwong
Published: August 2010

BACKGROUND:

Osteosarcoma is the most common malignant bone tumor in children. Despite the advent of chemotherapy, the survival of osteosarcoma patients has not been significantly improved recently. Chemokines are a group of signaling molecules that have been implicated in tumorigenesis and metastasis.

METHODS:

The authors used an antibody microarray to identify chemokines that were elevated in the plasma samples of osteosarcoma patients. The results were validated using enzyme‐linked immunosorbent assays on an independent set of samples. The tumor expressions of 3 chemokines were examined in 2 sets of osteosarcoma tissue arrays. The authors also evaluated the proliferative effect of the chemokines in 4 osteosarcoma cell lines.

RESULTS:

The authors found that the plasma levels of CXCL4, CXCL6, and CXCL12 in the osteosarcoma patients were significantly higher than those in the controls, and the results were validated by an independent osteosarcoma cohort (P < .05). However, CXCL4 (100%) and CXCL6 (91%) were frequently expressed in osteosarcoma, whereas CXCL12 was only expressed in 4%. Survival analysis further showed that higher circulating levels of CXCL4 and CXCL6, but not CXCL12, were associated with a poorer outcome of osteosarcoma patients. Addition of exogenous chemokines significantly promoted the growth of different osteosarcoma cells (P < .05).

CONCLUSIONS:

The results demonstrate that CXCL4 and CXCL6 are frequently expressed in osteosarcoma, and that the plasma levels of these 2 chemokines are associated with patient outcomes. Further study of these circulating chemokines may provide a promising approach for prognostication of osteosarcoma. Targeting these chemokines or their receptors may also lead to a novel therapeutic invention. Cancer 2011. © 2010 American Cancer Society.
Pegylated liposomal doxorubicin and gemcitabine in patients with advanced hepatocellular carcinoma
Authors: Lombardi Giuseppe , Zustovich Fable , Farinati Fabio , Cillo Umberto , Vitale Alessandro , Zanus Giacomo , Donach Martin , Farina Miriam , Zovato Stefania , Pastorelli Davide
Published: August 2010

BACKGROUND:

Over the years, doxorubicin and gemcitabine have been among the most widely used drugs for hepatocellular carcinoma (HCC), with relative efficacy. The authors report the results of a phase 2 study of the combination of gemcitabine plus pegylated liposomal doxorubicin.

METHODS:

Patients with advanced HCC received combination chemotherapy with gemcitabine 1000 mg/m2 on Days 1 and 8, followed by pegylated liposomal doxorubicin 30 mg/m2 on Day 1. Treatment was repeated every 4 weeks to a maximum of 8 cycles. Primary endpoint was overall response rate, and secondary endpoints were time to disease progression (TTP), overall survival (OS), and toxicity.

RESULTS:

Forty‐one patients were enrolled and were evaluable for response, toxicity, and survival. A total of 194 cycles of treatment were administered. Three (7%) patients had a complete response, and 1 of these patients underwent liver transplantation. Seven (17%) patients had a partial response and, among these patients, 1 patient underwent surgical resection. Among the 31 patients who had initial alpha‐fetoprotein levels >400 ng/mL, 20 (64.5%) had a >20% decrease after 2 cycles of treatment. The median TTP and OS were 5.8 and 22.5 months, respectively. Hematologic toxicity was the most common side effect, including neutropenia (17%) and anemia (7%).

CONCLUSIONS:

The combination of gemcitabine plus pegylated liposomal doxorubicin was active and safe in advanced HCC. Moreover, this treatment induced some complete responses and converted some untreatable HCCs into lesions eligible for resection or transplantation. Cancer 2011. © 2010 American Cancer Society.
Assessment of HER2 gene status in breast carcinomas with polysomy of chromosome 17
Authors: Vranic Semir , Teruya Bryan , Repertinger Susan , Ulmer Pamela , Hagenkord Jill , Gatalica Zoran
Published: August 2010

BACKGROUND:

The current study was performed to determine the impact of polysomy 17 on the interpretation of HER2 testing of invasive breast carcinomas using fluorescent in situ hybridization methods. Current American Society of Clinical Oncology/College of American Pathologists guidelines define HER2‐positive tumors as those with >6 HER2 genes per nucleus or those with HER2/CEP17 (chromosome 17) ratio >2.2. These guidelines are potentially contradictory in tumors with polysomy of chromosome 17.

METHODS:

Seventy‐two breast carcinoma cases with reported polysomy of chromosome 17 (≥3 CEP17 signals on average) by fluorescent in situ hybridization were identified, and the corresponding HER2 immunohistochemistry was obtained. The HER2 status of the archived samples was reviewed, and the tumors were recategorized according to the 2007 American Society of Clinical Oncology/College of American Pathologists guidelines.

RESULTS:

The average CEP17 copy number for the group was 4.5 (range, 3.0‐10.4). Thirty‐three (45.8%) cases had >6 copies of HER2 per nucleus. Twenty‐one cases (29.2%) qualified as HER2 gene amplified using the HER2/CEP17 ratio (>2.2) guideline. All these cases had >6 HER2 signals, which represented 63.6% of all cases with >6 HER2 signals. HER2 protein expression showed significant positive correlations with both HER2 gene copy number and HER2/CEP17 ratio (P < .01, rs = 0.56 and 0.64, respectively).

CONCLUSIONS:

Increased CEP17 signals detected in invasive breast carcinomas may lead to discordant interpretation of gene amplification in a significant proportion of the cases, depending on which criterion (ratio vs absolute number) is used for interpretation. However, increased gene dosage (>6 HER2 genes or HER2/CEP17 ratio >2.2), regardless of the evaluation method, is positively correlated with HER2 protein expression. Cancer 2011. © 2010 American Cancer Society.
Coronary revascularization and mortality in men with congestive heart failure or prior myocardial infarction who receive androgen deprivation
Authors: Nguyen Paul L. , Chen Ming H. , Goldhaber Samuel Z. , Martin Neil E. , Beard Clair J. , Dosoretz Daniel E. , Katin Michael J. , Ross Rudi , Salenius Sharon A. , D'Amico Anthony V
Published: August 2010

BACKGROUND:

A study was undertaken to determine the impact of prior coronary revascularization (angioplasty, stent, or coronary artery bypass graft) on the risk of all‐cause mortality after neoadjuvant hormonal therapy (HT) for prostate cancer (PC) in men with a history of coronary artery disease (CAD)‐induced congestive heart failure (CHF) or myocardial infarction (MI).

METHODS:

Among 7839 men who received radiation with or without a median of 4 months of HT for PC from 1991 to 2006, 495 (6.3%) had CAD‐induced CHF or MI and formed the study cohort. Of these men, 250 (50.5%) had been revascularized before treatment for PC. Cox regression was used to determine whether HT increased the risk of all‐cause mortality, and whether revascularization altered this risk, after adjusting for known PC prognostic factors and a propensity score for revascularization.

RESULTS:

Median follow‐up was 4.1 years. Neoadjuvant HT was associated with an increased risk of all‐cause mortality (28.9% vs 15.7% at 5 years; adjusted hazard ratio [HR], 1.73; 95% confidence interval [CI], 1.13‐2.64;P= .01). Men who received HT without revascularization had the highest risk of all‐cause mortality (33.3%; adjusted HR, 1.48; 95% CI, 1.01‐2.18;P= .047), whereas men who were revascularized and did not receive HT had the lowest risk of all‐cause mortality (9.4%; adjusted HR, 0.51; 95% CI, 0.28‐0.93;P= .028). The reference group had an intermediate risk of all‐cause mortality (23.4%) and was comprised of men in whom HT use and revascularization were either both given or both withheld.

CONCLUSIONS:

In men with a history of CAD‐induced CHF or MI, neoadjuvant HT is associated with an excess risk of mortality, which appears to be reduced but not eliminated by prior revascularization. Cancer 2011. © 2010 American Cancer Society.
Comparison of BD Surepath and ThinPrep Pap systems in the processing of mucus‐rich specimens
Authors: Kenyon Shelly , Sweeney Brenda J. , Happel James , Marchilli Gloria E. , Weinstein Barbara , Schneider Douglas
Published: August 2010

BACKGROUND:

Excessive mucus, as well as blood and inflammation, can be problematic in the processing and screening of liquid‐based cervical Pap preparations by interfering in the process of cell retrieval onto specimen filters or slides. This study compares the capacity of the BD SurePath and ThinPrep liquid‐based Papanicolaou (Pap) tests to handle mucus‐laden specimens.

METHODS:

A 100 μL volume of pooled cervical epithelial cells was added to BD SurePath and ThinPrep liquid Pap test vials. Aliquots of cervical mucus that had been collected and pooled from previously processed mucus‐rich Pap specimens were added to each series of test vials in amounts of 250 μL, 500 μL, 1000 μL, and 2000 μL. The vials were then routinely processed on their respective instruments and the test slides evaluated for cellularity of the squamous cell component.

RESULTS:

The BD SurePath test specimens showed no reduction of the squamous cell component resulting from the addition of any of the aliquots of mucus. The ThinPrep test specimens showed a marked loss of cellularity upon the addition of the first aliquot of mucus, with large areas of the filters showing nearly complete absence of squamous cells.

CONCLUSIONS:

Excessive mucus remains a potentially limiting factor in the ThinPrep Pap system. This appears to be the result of direct obstruction of the filtration membrane causing a markedly diminished retrieval of squamous epithelial cells and potentially impacting disease detection. The BD SurePath system, conversely, manages mucus by a cell enrichment process, which results in undiminished cell recovery as observed in this study's test conditions. Cancer (Cancer Cytopathol) 2010. © 2010 American Cancer Society.
Biomashups: the new world of exploratory bioinformatics?
Authors: Hogan James M. , Sumitomo Jiro , Roe Paul , Newell Felicity
Published: August 2010

Bioinformatics is dominated by online databases and sophisticated web‐accessible tools. As such, it is ideally placed to benefit from the rapid, purpose specific combination of services achievable via web mashups. The recent introduction of a number of sophisticated frameworks has greatly simplified the mashup creation process, making them accessible to scientists with limited programming expertise. In this paper we investigate the feasibility of mashups as a new approach to bioinformatic experimentation, focusing on an exploratory niche between interactive web usage and robust workflows, and attempting to identify the range of computations for which mashups may be employed. While we treat each of the major frameworks, we illustrate the ideas with a series of examples developed under the Popfly framework‡. Copyright © 2010 John Wiley & Sons, Ltd.
Archiving and accessing language resources
Authors: Wittenburg Peter
Published: August 2010

Languages are among the most complex systems that evolution has created. With an unforeseen speed many of these unique results of evolution are currently disappearing: every two weeks one of the 6500 still spoken languages is dying and many are subject to extreme changes due to globalization. Experts understood the need to document the languages and preserve the cultural and linguistic treasures embedded in them for future generations. Also linguistic theory will need to consider the variation of the linguistic systems encoded in languages to improve our understanding of how human minds process language material, thus accessibility to all types of resources is increasingly crucial. Deeper insights into human language processing and a higher degree of integration and interoperability between resources will also improve our language processing technology. The DOBES programme is focussing on the documentation and preservation of language material. The Max Planck Institute developed the Language Archiving Technology to help researchers when creating, archiving and accessing language resources. The recently started CLARIN research infrastructure has as main goals to achieve a broad visibility and an easy accessibility of language resources. Copyright © 2010 John Wiley & Sons, Ltd.
Hypercubic storage layout and transforms in arbitrary dimensions using GPUs and CUDA
Authors: Hawick K. A. , Playne D. P.
Published: August 2010

Many simulations in the physical sciences are expressed in terms of rectilinear arrays of variables. It is attractive to develop such simulations for use in 1‐, 2‐, 3‐ or arbitrary physical dimensions and also in a manner that supports exploitation of data‐parallelism on fast modern processing devices. We report on data layouts and transformation algorithms that support both conventional and data‐parallel memory layouts. We present our implementations expressed in both conventional serial C code as well as in NVIDIA's Compute Unified Device Architecture concurrent programming language for use on general purpose graphical processing units. We discuss: general memory layouts; specific optimizations possible for dimensions that are powers‐of‐two and common transformations, such as inverting, shifting and crinkling. We present performance data for some illustrative scientific applications of these layouts and transforms using several current GPU devices and discuss the code and speed scalability of this approach. Copyright © 2010 John Wiley & Sons, Ltd.
Visualizing space–time dynamics in scaling systems
Authors: Batty Michael
Published: August 2010

The signature of scaling in human systems is the well‐known power law whose key characteristic is that the size distributions of their objects display self‐similarity in space and time. In many systems such as cities, firms, and high buildings used here as examples, power laws represent an approximation to the fat or heavy tails of their rank‐size distributions, appearing stable in time with little change in their scaling over tens or even hundreds of years. However, when the detailed dynamics of how their ranks shift in time is examined, there is considerable volatility in such distributions. To explore this microvolatility, we introduce measures of rank shift over space and time and visualize size distributions using the idea of the “rank clock.” We illustrate this for populations of Italian towns between 1300 and 1861 and then compare this analysis with city‐size distributions for the world from 430 B.C.E., the United States from 1790, Great Britain (England, Scotland, Wales) from 1901, and Israel from 1950. When we extend this analysis to the distribution of US firms from 1955 and high buildings in New York City and the world from 1909, we generate a rich portfolio of space–time dynamics that adds to our understanding of how different systems can display stability and regularity at the macro level in the face of considerable volatility at the micro. © 2010 Wiley Periodicals, Inc. Complexity 16: 51–63, 2010
Time and space in neuronal networks: The effects of spatial organization on network behavior
Authors: Womble Stephen P. , Cohen Netta
Published: August 2010

Biological neural networks tend to exhibit a variety of spatial structures. Here, we study the effect of spatial embedding in a specific example motivated by cortical circuits in which inhibitory cells densely occupy a central region and are surrounded by a larger and more dispersed population of excitatory cells. To instantiate space, neuronal time delays are chosen to be proportional to the distance between neurons. We use simulations of spiking neural networks, operating close to a critical bifurcation between stationary behavior and population‐wide oscillatory behavior, whereas in a nonspatial network, shorter time delays tend to enhance stationary population dynamics; here, the imposition of space reverses the effect: the shorter the time delays, the more oscillatory the network becomes. We conclude that the specific geometries of spatial embedding and their subtle effects on the distributions of time delays in a network can have significant repercussions for network dynamics. © 2010 Wiley Periodicals, Inc. Complexity 16: 45–50, 2010
Factors associated with outcome of cognitive–behavioural therapy for complicated grief: A preliminary study
Authors: Boelen Paul A. , de Keijser Jos , van den Hout Marcel A. , van den Bout Jan
Published: August 2010

Complicated grief (CG), also called prolonged grief disorder, is a debilitating condition that can develop following a loss. There is growing evidence that cognitive–behavioural interventions are efficacious in the treatment of CG. The present preliminary study used data from 43 patients with CG who were randomly assigned to cognitive–behavioural therapy in an earlier treatment trial to explore (a) predictors of outcome of cognitive–behavioural therapy for CG and (b) the relationship between symptom improvement and changes in loss‐related negative cognitions and avoidance behaviours. Analyses showed that worse treatment outcome was associated with lower education attainment, loss of a partner/child (instead of some other relative), early treatment discontinuation, less patient motivation and more severe CG symptoms at pre‐treatment. As predicted, stronger reduction in CG severity was significantly associated with stronger reductions in negative cognitions and avoidance. Implications of these findings are discussed. Copyright © 2010 John Wiley & Sons, Ltd.

Key Practitioner Message:

• Greater effectiveness of cognitive–behavioural therapy (CGT) for complicated grief (CG) seems to be associated with higher educational level, being confronted with losses other than the loss of a partner or child, completion (and not early discontinuation) of treatment and stronger motivation.

• Longer CBT treatment may be needed for CG patients bereaved by the loss of a partner or child and mourners with more severe levels of CG.

• Seeking ways to enhance patient motivation and adherence to treatment seems important to improve the effectiveness of CBT for CG.

• Reduction in CG severity during CGT is associated with reduction in negative cognitions and avoidance behaviours.
Relationship between the Social Cognition and Object Relations Scale (SCORS) and attachment style in a clinical sample
Authors: Stein Michelle B. , Siefert Caleb J. , Stewart Rosemarie Vala , Hilsenroth Mark J.
Published: August 2010

This present study examined the relationship between the Social Cognition and Object Relations Scale (SCORS) and two measures of adult attachment: the Relationship Questionnaire (RQ) and the Experiences in Close Relationships Questionnaire‐Revised (ECR‐R). Forty‐five patients (76% female) at a university‐based outpatient treatment clinic participated in this study. We hypothesized that higher levels of attachment security would be associated with higher, more adaptive ratings on the SCORS variables. Results indicated that the SCORS Self‐Esteem (SE) variable was significantly positively related to the RQ's Secure Attachment ratings and negatively related with the ECR‐R's Anxious Attachment scale. Additionally, negative trends were noted between SE and the RQ's Fearful and Preoccupied Attachment scores. The SCORS Emotional Investments in Relationships and Affective Quality of Representations variables were associated with higher Secure scores and lower, more maladaptive Preoccupied scores on the RQ. It was also associated with greater attachment anxiety as measured by the ECR‐R. Using both clinician (SCORS) and participant‐rated measures (ECR‐R and RQ), this study provides further understanding on how object representations and attachment style relate within a clinical sample. Results are discussed in light of prior research examining relationships between object relations and adult attachments, and clinical implications are also reviewed. Copyright © 2010 John Wiley & Sons, Ltd.

Key Practitioner Message:

• Individuals with higher levels of attachment anxiety may enter therapy with more self‐image problems.

• Individuals with higher levels of attachment anxiety may enter therapy with more maladaptive expectations about relationships.

• Patients who endorse high levels of attachment anxiety (e.g., fearful and preoccupied) may be more likely to present with Axis II complaints.

• Examining a patient's attachment style and object relations using different measures of assessment (e.g., explicit and implicit) can help gain a deeper and more comprehensive understanding of a patient.
Structural, thermal and optical studies on 2‐naphthol crystals
Authors: Guru Prasad L. , Krishnakumar V. , Shanmugam G. , Nagalakshmi R.
Published: August 2010

Single crystals of 2‐naphthol was grown in slow evaporation solution growth technique. Grown crystals were characterized by various characterization techniques. Powder X‐ ray diffraction studies reveal that the grown crystal belongs to monoclinic system with noncentrosymmetric space group. Vibrational bands of the various functional groups and their significance were investigated by analyzing the vibrational spectra. Melting point and the decomposition temperature of the grown crystal was premeditated from the thermal analysis. From the UV‐VIS‐NIR spectrum the electronic excitation mechanism and the transmittance abilities of the crystal was studied. Theoretical value of first static hyperpolarizability was calculated and compared with urea. Second harmonic generation efficiency of the crystal is 0.6 times that of KDP. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Universal basis for ranking small‐signal aspects of compensation techniques for operational amplifiers
Authors: Cherry Edward M.
Published: August 2010

A multi‐pole gain‐bandwidth theorem sets an upper bound to the bandwidth that can be achieved with specified DC gain and external load capacitance, for a given selection of transistors and operating points. A product of the poles and zeros is constrained by ∏(gm/C) evaluated over the forward‐path active devices. Most practical compensation techniques degrade the actual bandwidth, by factors which the paper explores in detail; depending on the circuit topology, some compensating capacitors can add to the intrinsic device capacitances. A few techniques achieve the ideal. Copyright © 2010 John Wiley & Sons, Ltd.
Silicon Carbonitride (SiCN) Films by Remote Hydrogen Microwave Plasma CVD from Tris(dimethylamino)silane as Novel Single‐Source Precursor
Authors: Wrobel Aleksander M. , Blaszczyk‐Lezak Iwona , Uznanski Pawel , Glebocki Bartosz
Published: August 2010

SiCN films were produced by remote microwave hydrogen plasma CVD (RP‐CVD) from tris(dimethylamino)silane precursor using different substrate temperature in the range TS=30‐400°C. The effect of TS on the rate of RP‐CVD, chemical structure, surface morphology, density, and photoluminescence (PL) of resulting films is reported. The increase in TS causes the formation of silicon carbonitride network, marked densification and smoothening of film surface, as well as shift of PL peak position.
Growth of [100]‐Textured Gadolinium Nitride Films by CVD
Authors: Brewer Joseph R. , Gernhart Zane , Liu Hsin‐Yu , Cheung Chin Li
Published: August 2010

Textured gadolinium nitride (GdN) thin films grown on (100) lanthanum aluminum oxide substrates were prepared by chemical vapor deposition with gadolinium chloride and ammonia. The films were found to have a (100) planar orientation and a growth rate of 102±5nm/min. X‐ray diffraction patterns show that the (200) reflection peaks from these GdN films have full widths at half maximum of ca. 1.2°.
Multifunctional Nanocomposite Thin Films by Aerosol‐Assisted CVD
Authors: Warwick Michael E.A. , Dunnill Charles W. , Binions Russell
Published: August 2010

The aerosol‐assisted (AA)CVD reaction of titanium isopropoxide and a solution of preformed tin dioxide nanoparticles leads to the production of titanium dioxide/tin dioxide nanocomposite thin films on glass substrates. Scanning electron microscopy (SEM) studies show that film composition and morphology are linked, with larger island sizes being observed as more tin dioxide nanoparticles are incorporated into the films. Reflectance measurements performed on the nanocomposite thin films show an increase in reflection in the infrared (IR) portion of the spectrum with increased tin dioxide nanoparticle incorporation. Photocatalysis experiments indicate that the nanocomposite films are photo‐active with irradiation by 365 nm light. The nanocomposite thin films display both low‐emissivity and self‐cleaning functionalities; and as such they are multifunctional.
Investigation of Atmospheric Pressure CVD‐Produced Aluminum Coatings for the Protection of Steel from Corrosion
Authors: Gu Sipeng , Maeng Sungmin , Suh Yongseok , Levy Roland A. , Deavenport Dennis L. , Gómez Fernando J. , Newberg Samuel S. , Brooman Eric W. , Berman Elizabeth S. , Kleek John J. , Beatty John H. , Schwartz Andrew S. , Gaydos Stephen P.
Published: August 2010

This study investigates the use of atmospheric pressure (AP)CVD‐produced aluminum (Al) coatings for the protection of steel from corrosion. Coatings produced through thermal decomposition of a triisobutylaluminum (TIBAL)‐based precursor at 548 and 573 K are shown to exhibit growth rates of 0.5 and 1.1 µm min−1, respectively. Glow discharge optical emission spectroscopy (GDOES) reveals that, in the main, the coatings consist of pure Al with oxygen present as a minor constituent. Results of the structural, morphological, electrical, and mechanical characterization reveal that the APCVD Al coatings exhibit a face center cubic (fcc) structure with no preferred orientation, a non‐columnar grain structure with grain size ranging from 3 to 10 µm, and a surface roughness close to 2 µm. Such coatings are also shown to offer an electrical resistivity of 3.5 µΩ·cm, a density of 2.60 g cm−3, and an adhesive strength of 703 kg cm−2. Cross‐sectional examination of coated samples indicate that the APCVD process can yield excellent step coverage and throwing power. Hydrogen embrittlement (HE) tests reveal that Al‐coated bars with no post baking experience premature failure due to the presence of incorporated reaction product, hydrogen, in the steel substrate. Samples post‐baked at 463 K for 23 h to remove the hydrogen from the substrate are shown to withstand the load for as long as 202 h. Corrosion studies conducted using potentiodynamic polarization measurements, electrochemical impedance spectroscopy, and salt fog tests show that the corrosion resistance of the APCVD Al coatings is comparable to that of pure Al foils, and that such coatings provide acceptable sacrificial protection for steel substrates.
A simple method to sort ESC‐derived adipocytes
Authors: Schaedlich Kristina , Knelangen Julia M. , Navarrete Santos Alexander , Fischer Bernd , Navarrete Santos Anne
Published: August 2010

Because of the increasing incidence of worldwide obesity, cell culture models which enable the study of adipose tissue development are of particular importance. The murine embryonic stem cell (ESC) line CGR8 differentiates into adipocytes with a differentiation efficiency of up to 15%. A critical step for the analysis of stem cell‐derived adipogenesis is the reliable separation of adipocytes. Here we report on how to (i) gently separate the cells of embryoid bodies (EBs) and (ii) identify and sort adipocytes from the rest of the heterogeneous cell mixture. Up to the present, no adipocyte specific surface marker is known for fluorescence activated cell sorting (FACS). After separation we employed two independently existing FACS methods for adipocyte cell sorting. These methods are based on Nile red staining and granularity. For stem cell‐derived adipocytes only the combination of both methods led to a reliable, efficient, and highly reproducible FACS analysis, as shown by the presence and absence of adipocyte specific markers in positively and negatively sorted cells. © 2010 International Society for Advancement of Cytometry
Flow cytometric analysis of CD123 is useful for immunophenotyping classical Hodgkin lymphoma
Authors: Fromm Jonathan R.
Published: August 2010

Although the diagnosis of classical Hodgkin lymphoma (CHL) is traditionally made morphologically in tissue sections, it is now possible to diagnose CHL by flow cytometry (FC). In an effort to identify additional antigens on Hodgkin and Reed‐Sternberg (HRS) cells that might be useful for immunophenotyping this lymphoma by FC, we examined the expression of CD123 (α chain of the IL‐3R) on HRS cells and compared this with the expression of CD123 in other lymph node samples (372 tissue specimens, including 98 reactive and 274 neoplastic cases), using a nine‐color FC reagent combination including anti‐CD123. CD123 was found to be expressed on the majority of HRS cell populations (59% of 59 CHL lymph nodes examined), rarely on B‐cell non‐Hodgkin lymphomas (NHLs) (3 of 3 hairy cell leukemia cases, 3 of 29 chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL) cases, 1 of 55 large B‐cell lymphoma cases, but not on 95 other B‐cell NHL examined), and in none of the 16 T‐cell NHL cases examined. In reactive lymph nodes, CD123 expression was largely limited to plasmacytoid dendritic cells and rare histiocyte populations that can readily be distinguished from HRS populations. As the expression of this antigen is shown to be relatively limited in B‐ and T‐NHL and in reactive lymph node populations, assessment of CD123 expression is useful for supporting the FC diagnosis of CHL. © 2010 International Clinical Cytometry Society
Performance improvement of fixed wireless access networks by conjunction of dual polarization and time domain radio resource allocation technique
Authors: Vavoulas Alexander , Vaiopoulos Nicholas , Varoutas Dimitris A. , Chipouras Aris , Stefanou George
Published: August 2010

This paper considers the impact of dual polarization adoption on the performance for a fixed wireless access (FWA) network. The major limiting factor of the performance in these systems is co‐channel interference (CCI) originating from intracell and intercell concurrent transmissions. The proposed framework combines an appropriate time domain radio resource allocation technique with a dual polarization pattern to mitigate CCI and enhance the obtained signal to interference plus noise ratio (SINR). Simulation results present the performance of the proposed framework against various terrain categories and sector antenna characteristics. Copyright © 2010 John Wiley & Sons, Ltd.
Adam10 is essential for early embryonic cardiovascular development
Authors: Zhang Chi , Tian Lei , Chi Congwu , Wu Xiaohui , Yang Xiao , Han Min , Xu Tian , Zhuang Yuan , Deng Kejing
Published: August 2010

Notch pathway has been demonstrated to regulate cardiovascular development. One important step in Notch pathway is the cleavage of Notch receptor, during which an intracellular fragment of Notch protein is released to activate downstream genes. It is still uncertain whether Adam10, the mammalian homologue of Kuzbanian in Drosophila, is required to activate the Notch pathway during cardiovascular development. To further understand the physiological function of Adam10 in vascular and cardiac development, we generated mice lacking the Adam10 gene primarily in the endothelial compartment. We found that disruption of Adam10 in endothelial cells resulted in embryonic death after embryonic day 10.5 due to multiple cardiac and vascular defects similar to Notch1 mutants. We further showed that the expression of Notch target genes Snail and Bmp2 are impaired in Adam10‐deficient cardiac tissues. Finally, we provide experimental evidence to support that Adam10 functions in a cell autonomous manner during mammalian cardiac development. Developmental Dynamics 239:2594–2602, 2010. © 2010 Wiley‐Liss, Inc.
Synthesis and Electrochemical Study of an Original Copper(II)‐Capped Salen–Cyclodextrin Complex
Authors: Deunf Elise , Zaborova Elena , Guieu Samuel , Blériot Yves , Verpeaux Jean‐Noël , Buriez Olivier , Sollogoub Matthieu , Amatore Christian
Published: August 2010

A new metallocapped cyclodextrin (CD) was synthesized by the regioselective debenzylation, induced by diisobutylaluminium hydride (DIBAL‐H), of perbenzylated cyclodextrins. This reaction allowed for the efficient preparation of an unprecedented CD–salen type copper(II) complex. The electrochemical behavior of both the bound and unbound CD–salen compounds was investigated by cyclic voltammetry. Notably, it was shown that the presence of tert‐butyl groups at the ortho‐ and para‐positions of the salen aromatic rings stabilized the copper(II) phenoxyl radical species that was generated upon the one‐electron oxidation of the starting compound. Importantly, this stabilization remained effective when the salen‐type ligand was covalently attached to the CD. This allowed for investigations of the reactivity of the copper(II) phenoxyl radical complex towards a primary alcohol to be performed by cyclic voltammetry. This reaction can be considered as mimicking the behavior of galactose oxidase. However, under these conditions, no reactivity was observed in the presence of benzyl alcohol. This may be due to distortion, either of the initially square planar salen ligand after its grafting to the CD primary face, and/or of the CD itself. On the other hand, the electrochemical reduction of the un‐grafted copper(II) salen‐type ligand led to a transient anionic species that exhibited significant stability on the time‐scale of the slow cyclic voltammetry measurement in the absence of the CD, but was unstable in the presence of the CD. In the latter case, it was demonstrated that the anionic species was protonated by the CD. Importantly, this protonation was not fast enough to prevent catalytic activation of iodomethane by the electro‐generated copper(I)‐capped salen CD complex.