bluuebunny/crossref_metadata_2025 huggingface dataset:
Phase Behavior of CO2 in Room‐Temperature Ionic Liquid 1‐Ethyl‐3‐Ethylimidazolium Acetate
Authors: Shiflett Mark B. , Elliott Beth A. , Lustig Steve R. , Sabesan Subramaniam , Kelkar Manish S. , Yokozeki A.
Published: April 2012

Carbon dioxide solubility (vapor–liquid equilibria: VLE) in an ionic liquid, 1‐ethyl‐3‐ethylimidazolium acetate ([eeim][Ac]) was measured using a gravimetric microbalance at four isotherms (about 283, 298, 323, and 348 K) up to about 2 MPa. An equation‐of‐state (EOS) model was used to analyze the VLE data and has predicted vapor–liquid–liquid equilibria (VLLE: or liquid–liquid separations) in CO2‐rich solutions. The VLLE prediction was confirmed experimentally using a volumetric method and likely the liquid–liquid equilibria will intersect with the solid–liquid equilibria such that no lower critical solution temperature can exist and the binary system may be classified as Type III phase behavior. Carbon dioxide solubility in the ionic‐liquid‐rich solution show extremely unusual behavior. CO2 dissolves in the ionic liquid at large concentrations (up to about 20 mole % of CO2) with almost no vapor pressure above the mixtures. This result is similar to our previous findings with 1‐butyl‐3‐methylimidazolium acetate ([bmim][Ac]) and 1‐ethyl‐3‐methylimidazolium acetate ([emim][Ac]). In all three cases the CO2 forms a molecular complex (or chemical reaction) with the ionic liquid. 13C NMR spectroscopy has identified the structure for CO2 absorbed in [eeim][Ac] to be [eeim]‐2‐carboxylate. Addition of water to the carboxylate leads to the dissolution of CO2. The thermodynamic excess properties (enthalpy, entropy, and Gibbs energy) for all three systems have been calculated using the EOS and support the complex formation of the type AB2 (where A is CO2 and B is ionic liquid). Isothermal differential scanning calorimetry has verified the heat of reaction calculations and found for CO2 absorbing in [emim][Ac], [eeim][Ac] and [bmim][Ac] to be about −38 kJ mol−1. Additional experiments have examined the effect of water on the density, viscosity and CO2 solubility in [eeim][Ac] and the CO2 solubility in mixtures of [eeim][Ac] with other acetate salts.
Collapse of Homeotropic Liquid‐Crystal Alignment by Increased Molecular Packing on Comb‐Like Polymer Surfaces
Authors: Sohn Eun‐Ho , Kang Hyo , Kim Dong‐Gyun , Song Kigook , Lee Jong‐Chan
Published: April 2012

We report an unusual alignment behavior of liquid crystals (LCs) on well‐ordered comb‐like poly(oxyethylene) surfaces. The homeotropic LC alignments that are observed on as‐coated surfaces of the polymers are transformed to the random planar type after annealing treatment, even though the molecular structure of the polymer surface becomes more ordered and the surface energy decreases. Studies of the surface properties, such as molecular structure, morphology, and wettability, reveal that such an unexpected alteration of the LC alignment originates from the density of the alkyl side chains being enhanced by localized packing.
The effects of a freeze‐thaw cycle and pre‐analytical storage temperature on the stability of insulin‐like growth factor‐I and pro‐collagen type III N‐terminal propeptide concentrations: Implications for the detection of growth hormone misuse in athletes
Authors: Guha Nishan , Erotokritou‐Mulligan Ioulietta , Bartlett Christiaan , A. Cowan David , Bassett E. Eryl , Stow Michael , Sönksen Peter H , Holt Richard IG
Published: April 2012

A method based on two serum biomarkers – insulin‐like growth factor‐I (IGF‐I) and pro‐collagen type III N‐terminal propeptide (P‐III‐NP) – has been devised to detect growth hormone (GH) misuse. The aims of this study were to determine the stability of IGF‐I and P‐III‐NP concentrations in serum stored at −20°C and to establish the effects of one freeze‐thaw cycle.

Blood was collected from 20 healthy volunteers. Serum aliquots were analyzed after storage for one day at 4°C and one day, one week, five weeks, and three months at −20°C. IGF‐I and P‐III‐NP results were combined to calculate a GH‐2000 discriminant function score for each volunteer. Inter‐assay precision was determined by analysing one quality control sample at each time‐point.

A single freeze‐thaw cycle, storage of serum at 4°C for one day and at −20°C for up to three months had no significant effect on IGF‐I or P‐III‐NP concentration. Intra‐sample variability for IGF‐I was 6.8% (Immunotech assay) and 12.9% (DSL assay). Intra‐sample variability for P‐III‐NP was 10.9% (Cisbio assay) and 13.7% (Orion assay). When IGF‐I and P‐III‐NP results were combined, intra‐sample variability of the GH‐2000 score expressed as a standard deviation varied between 0.31 and 0.50 depending on the assay combination used. Variability in IGF‐I and P‐‐III‐NP results of stored samples is largely determined by the characteristics of the assays. A single freeze‐thaw cycle, storage of serum at 4°C for one day or at −20°C for up to 3 months does not result in a significant change in GH‐2000 score. Copyright © 2012 John Wiley & Sons, Ltd.
Impact of carrier frequency offset on the capacity of MIMO‐OFDM systems
Authors: Tutgun Rasit , Aktas Emre
Published: April 2012

Carrier frequency offset (CFO) is a factor that corrupts subchannel orthogonality resulting to performance degradation in multiple‐input multiple‐output orthogonal frequency division multiplexing systems. We investigate the effect of CFO on the channel estimation and the effect of both CFO and channel estimation on the system capacity. The main result of the paper is a lower bound on the capacity for a given CFO and channel estimation error covariance. The lower bound is based on the Gaussian bound of the multiplicative noise because of channel estimation errors. Copyright © 2012 John Wiley & Sons, Ltd.
SUSTAINABLE GROUNDWATER USE IN AGRICULTURE
Authors: Madramootoo Chandra A.
Published: April 2012

With the increasing competition for fresh water, there is a growing reliance on the abstraction of groundwater for irrigated agriculture. Groundwater irrigation demand has been growing steadily over the past decades, for many reasons including the unreliability of the traditional large canal schemes, and the increasing need of farmers to manage their own irrigation applications. In addition, unpredictability in climate has forced some farmers, particularly in semi‐arid areas, to exploit groundwater, in order to combat drought. The increasing overexploitation of important aquifers around the world, as well as groundwater contamination must be of concern to water resource planners and managers. Groundwater is a finite resource, and little is being done to accurately map, assess, monitor and regulate groundwater development for agriculture. Unconstrained and unregulated groundwater development is already impacting negatively on agricultural growth in over 111 million ha of irrigated lands, and innumerable livelihoods that rely on groundwater. Any attenuation of growth will make it more difficult to feed 9 billion people by 2050. A more proactive and integrated approach to groundwater governance, management and protection, built upon sound technical, institutional, legal, socio‐economic and environmental principles is required. Copyright © 2012 John Wiley & Sons, Ltd.
LIMITATION OF AGRICULTURAL GROUNDWATER USES IN BEAUCE (FRANCE): WHAT ARE THE IMPACTS ON FARMS AND ON THE FOOD‐PROCESSING SECTOR?
Authors: Lejars C. , Fusillier J.L. , Bouarfa S. , Coutant C. , Brunel L. , Rucheton G.
Published: April 2012

Many farmers, and the large set of downstream operators who depend on their farm products, have become dependent on groundwater resources, which are declining in many parts of the world. Farmers have to reduce water consumption by growing crops with lower water requirements, or apply optimal irrigation strategies. The strategies they choose can have major consequences for downstream operators and agro‐industries.

This paper presents an analysis of the impacts on, and consequences of, high water restrictions for the subsectors. The analysis was conducted in collaboration with local stakeholders in the region of Beauce, France. Adaptations and strategies to face up to reduced water availability were analysed in economic and technical terms for both farmers and downstream operators. Participatory workshops brought together different downstream operators who could become competitors for the same resource and highlighted interactions between operators in the same subsector as well as interactions between different sectors. Copyright © 2012 John Wiley & Sons, Ltd.
EARLY HEAD START HOME VISITATION: THE ROLE OF IMPLEMENTATION IN BOLSTERING PROGRAM BENEFITS
Authors: Jones Harden Brenda , Chazan‐Cohen Rachel , Raikes Helen , Vogel Cheri
Published: April 2012

Home visitation has emerged as a key strategy for promoting child and family well‐being in the current policy context. This article examines the effectiveness of the Early Head Start (EHS) home‐based program for children and families at the end of the program and 2 years later, with a particular focus on the role of program implementation in the impacts of the EHS home‐based program on child and family outcomes. There was a pattern of broad, modest effects of EHS home visiting for both children and parents, which were strengthened if the programs were fully implemented according to federal guidelines. In particular, impacts for children in the cognitive and language domain were documented. Implications of these findings for policy and practice are discussed.
CONCEPTUALIZING SOCIAL INTEGRATION AMONG FORMERLY HOMELESS ADULTS WITH SEVERE MENTAL ILLNESS
Authors: Tsai Jack , Rosenheck Robert A.
Published: April 2012

The multiple dimensions of social integration among formerly homeless adults with severe mental illness have not been well‐studied. Previous studies have focused on clinical measures or narrow components of social integration. We used a multisite study of chronically homeless adults who were provided housing to (a) identify the main factors related to social integration, (b) examine the association between clinical symptoms and social integration, and (c) examine whether social integration is associated with life satisfaction. A factor analysis identified six components of social integration: housing, community participation, civic activities, religious faith, social support, and treatment support. Social integration was found to be largely independent of clinical symptoms and had only a weak association with life satisfaction. These findings suggest supported housing programs needed to focus on improving client outcomes in several domains of social integration regardless of symptoms and that additional efforts are needed to improve life satisfaction among clients.
Locomotor Development of Zebrafish (Danio Rerio) Under Novel Hydrodynamic Conditions
Authors: DANOS NICOLE
Published: April 2012

The kinematics, neuromuscular control, and hydrodynamic aspects of normal locomotor activity in larval zebrafish have been extensively studied. Although locomotion depends heavily on the fluid properties of water, we have little knowledge of what sensory and developmental cues zebrafish larvae receive from their interaction with the fluid medium in which they grow. In this study, I manipulate the viscosity of water in which larvae grow until 5 and 7 days postfertilization (dpf) and record the kinematics of routine turns in their growth medium. Larvae are then transferred to a new medium of different viscosity and filmed again after short and long acclimation periods. Four hypotheses are tested: (1) larval kinematics are constrained by muscle activation patterns, (2) larval kinematics are guided by kinematic objectives, (3) routine turning control is independent of early locomotor experience, and (4) response to novel fluid environment is independent of developmental stage. The results indicate that a kinematic parameter, stage 1 angle, correlates with the kinematics of stage 1 while muscle activation patterns likely constrain stage 2. Development of this behavior is not dependent on locomotor experience both at 5 and 7 dpf, although the two age groups respond differently to increased viscosity. J. Exp. Zool. 317:117–126, 2012. © 2012 Wiley Periodicals, Inc.
A refined index of model performance: a rejoinder
Authors: Legates David R. , McCabe Gregory J.
Published: April 2012

Willmott et al. [Willmott CJ, Robeson SM, Matsuura K. 2012. A refined index of model performance. International Journal of Climatology, forthcoming. DOI:10.1002/joc.2419.] recently suggest a refined index of model performance (dr) that they purport to be superior to other methods. Their refined index ranges from − 1.0 to 1.0 to resemble a correlation coefficient, but it is merely a linear rescaling of our modified coefficient of efficiency (E1) over the positive portion of the domain of dr. We disagree with Willmott et al. (2012) that dr provides a better interpretation; rather, E1 is more easily interpreted such that a value of E1 = 1.0 indicates a perfect model (no errors) while E1 = 0.0 indicates a model that is no better than the baseline comparison (usually the observed mean). Negative values of E1 (and, for that matter, dr < 0.5) indicate a substantially flawed model as they simply describe a ‘level of inefficacy’ for a model that is worse than the comparison baseline. Moreover, while dr is piecewise continuous, it is not continuous through the second and higher derivatives. We explain why the coefficient of efficiency (E or E2) and its modified form (E1) are superior and preferable to many other statistics, including dr, because of intuitive interpretability and because these indices have a fundamental meaning at zero.

We also expand on the discussion begun by Garrick et al. [Garrick M, Cunnane C, Nash JE. 1978. A criterion of efficiency for rainfall‐runoff models. Journal of Hydrology 36: 375‐381.] and continued by Legates and McCabe [Legates DR, McCabe GJ. 1999. Evaluating the use of “goodness‐of‐fit” measures in hydrologic and hydroclimatic model validation. Water Resources Research 35(1): 233‐241.] and Schaefli and Gupta [Schaefli B, Gupta HV. 2007. Do Nash values have value? Hydrological Processes 21: 2075‐2080. DOI: 10.1002/hyp.6825.]. This important discussion focuses on the appropriate baseline comparison to use, and why the observed mean often may be an inadequate choice for model evaluation and development. Copyright © 2012 Royal Meteorological Society
Clinical trials in gastric cancer and the future
Authors: Mihaljevic André L. , Friess Helmut , Schuhmacher Christoph
Published: April 2012

Following the first successful gastric resection for gastric cancer by Theodor Billroth in 1881 surgery has made tremendous progress leading to improved surgical mortality and morbidity. However, while treatment of early gastric cancer is frequently curative, 5‐year survival rates for advanced gastric cancer remain dismal despite the application of perioperative multimodal treatment concepts. In this article we will outline key clinical trials that have lead to an improvement in treatment of gastric cancer patients with specific emphasis on the last 20 years. We will then outline recent concepts and key clinical trials that are currently being conducted in the field. Finally we will outline open questions that remain to be elucidated in the future. J. Surg. Oncol. 2013;107:289–297. © 2012 Wiley Periodicals, Inc.
Rapid Synthesis of Polymer Brush Surfaces via Microwave‐Assisted Surface‐Initiated Radical Polymerization
Authors: Guo Wei , Hensarling Ryan M. , LeBlanc Arthur L. , Hoff Emily A. , Baranek Austin D. , Patton Derek L.
Published: April 2012

Microwave‐assisted surface‐initiated radical polymerization (μW‐SIP) is demonstrated for the rapid synthesis of polymer brush surfaces on two‐dimensional substrates. μW‐SIP is carried out at constant temperature and microwave power allowing comparison with conventional SIP carried out in an oil bath at the same effective solution temperature. We show μW‐SIP enables significant enhancements (up to 39‐fold increase) in brush thickness at reduced reaction times for a range of monomer types (i.e. acrylamides, acrylates, methacrylates, and styrene). The effects of reaction time, monomer concentration, and microwave power on film thickness are explored.
Creating ‘buzz’: opportunities and limitations of social media for arts institutions and their viral marketing
Authors: Hausmann Andrea
Published: April 2012

According to empirical studies, two thirds of the people worldwide who surf the Internet use Web 2.0 applications (i.e. social media such as YouTube, Facebook or Twitter). The rate of growth is especially impressive in Germany, where the reluctance to publish personal information has traditionally been greater than in other countries. Accordingly, more and more German cultural suppliers seek to explore the possibilities of Web 2.0 and social media for their marketing objectives. In times of a general information overflow, declining credibility of traditional communication tools and a continued shortage of resources in the cultural sector, the fact that these web‐based applications can facilitate viral marketing and stimulate word‐of‐mouth is of special interest to arts institutions. However, until now, arts marketing has seen hardly any research on this topic. Therefore, the objective of this paper was to analyse the opportunities and limitations of Web 2.0 and social media for the viral marketing of arts institutions, especially with regard to their impact on quality and/or behavioural uncertainty on the part of visitors. The task setting will be carried out under consideration of the economics of information approach and explorative data.

Copyright © 2012 John Wiley & Sons, Ltd.
Crisis leadership: a view from the executive suite
Authors: Jaques Tony
Published: April 2012

Crisis leadership has become a strong element of crisis management scholarship, yet much of the published research is primarily observational, based on the performance of leaders in crisis situations or prescriptions for preferred behaviour. By contrast, this paper builds on in‐depth interviews with CEOs and top executives who provide a rare and remarkably frank view from the executive suite about the current state of crisis management and in particular about the role of corporate leaders in crisis prevention and preparedness. The heavily regulated chemical industry is seen as something of a bellwether for crisis management, and the paper details the perspective from leaders themselves, namely top executives in the chemical and petrochemical industry in Australia, representing some of the world's largest multinational corporations. The paper explores the reasons perceived at the executive level for why top executives often fail to provide the necessary openness, leadership and prioritization to prevent and prepare for organizational crises. Copyright © 2012 John Wiley & Sons, Ltd.
Tandem duplication of chromosomal segments is common in ovarian and breast cancer genomes
Authors: McBride David J , Etemadmoghadam Dariush , Cooke Susanna L , Alsop Kathryn , George Joshy , Butler Adam , Cho Juok , Galappaththige Danushka , Greenman Chris , Howarth Karen D , Lau King W , Ng Charlotte K , Raine Keiran , Teague Jon , Wedge David C , Cancer Study Group Australian Ovarian , Caubit Xavier , Stratton Michael R , Brenton James D , Campbell Peter J , Futreal P Andrew , Bowtell David DL
Published: April 2012

The application of paired‐end next generation sequencing approaches has made it possible to systematically characterize rearrangements of the cancer genome to base‐pair level. Utilizing this approach, we report the first detailed analysis of ovarian cancer rearrangements, comparing high‐grade serous and clear cell cancers, and these histotypes with other solid cancers. Somatic rearrangements were systematically characterized in eight high‐grade serous and five clear cell ovarian cancer genomes and we report here the identification of > 600 somatic rearrangements. Recurrent rearrangements of the transcriptional regulator gene, TSHZ3, were found in three of eight serous cases. Comparison to breast, pancreatic and prostate cancer genomes revealed that a subset of ovarian cancers share a marked tandem duplication phenotype with triple‐negative breast cancers. The tandem duplication phenotype was not linked to BRCA1/2 mutation, suggesting that other common mechanisms or carcinogenic exposures are operative. High‐grade serous cancers arising in women with germline BRCA1 or BRCA2 mutation showed a high frequency of small chromosomal deletions. These findings indicate that BRCA1/2 germline mutation may contribute to widespread structural change and that other undefined mechanism(s), which are potentially shared with triple‐negative breast cancer, promote tandem chromosomal duplications that sculpt the ovarian cancer genome. Copyright © 2012 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Persistence of humoral immunity to tetanus and diphtheria in hematopoietic stem cell transplant recipients after post‐transplant immunization
Authors: Škovránková Jitka , Petráš Marek
Published: April 2012

Background

Persistence of humoral immunity was evaluated in 82 hematopoietic stem cell transplant recipients up to 12.5 years after post‐transplant immunization against tetanus and diphtheria.

Procedure

New immunization, initiated at least 12 months after transplantation, consisted of an average three‐dose schedule of vaccine administration on day 1, month 3, and month 12. Serological data were collected at pre‐transplant, post‐transplant, vaccination, and post‐vaccination time points.

Results

The first vaccination dose elicited a seroprotective response in most recipients, but the complete vaccine series (usually three‐dose schedule) reinforced the specific immunity in most vaccinated cases, that is, 100% and 95.8% seroprotection against tetanus and diphtheria, respectively. Geometric mean concentration post‐vaccination tetanus and diphtheria antibody levels persisted at 1.9 IU (95% CI: 1.23–2.94 IU/ml) and 0.20 IU (95% CI: 0.11–0.38 IU/ml) for 7 years, respectively. However, diphtheria antibodies were lost not significantly but much faster and more often than tetanus antibodies, though the seroprotection rates against tetanus and diphtheria remained favorable, that is, 100% (95% CI: 85.2–100%) and 87% (95% CI: 59.5–98.3%), respectively.

Conclusions

Full post‐transplant revaccination resulted in long‐term persistence of humoral immunity against tetanus and diphtheria in SCT recipients, for an average of 8.6 and 9.0 years, respectively. Pediatr Blood Cancer 2012; 59: 908–913. © 2012 Wiley Periodicals, Inc.
Sex‐specific differences in the concentration of tubular parameters in the amniotic fluid of second trimester fetuses
Authors: Tzschoppe Anja , Rauh Manfred , Goecke Tamme W. , Yazdi Britta , Hart Nicola , Siemer Jörn , Schild Ralf L. , Dötsch Jörg
Published: April 2012

Objective

Renal dysplasia and obstructive uropathy are more common in males and are associated with an increased tubular loss of electrolytes. We aimed to compare the midtrimester concentration of tubular parameters in the prenatal period between healthy male and female fetuses.

Methods

Amniotic fluid was collected at 16 weeks of gestation at the time of genetic amniocentesis. The concentration of sodium, chloride, potassium, calcium, phosphate, magnesium, α1‐microglobulin, creatinine and urea was determined in the amniotic fluid of 92 male and 108 female fetuses.

Results

The concentration of sodium, chloride and calcium was not significantly higher in male than in female fetuses. In contrast, the concentration of potassium (p = 0.01), phosphate (p = 0.04), magnesium (p = 0.04) and α1‐microglobulin (p = 0.04) was significantly increased in the amniotic fluid of male fetuses. The concentration of electrolytes correlated to the concentration of creatinine, urea and α1‐microglobulin.

Conclusion

The concentration of specific tubular parameters in the amniotic fluid was higher in male compared with female fetuses. Whether this might point to sex‐specific differences in tubular function in second trimester fetuses or reflect glomerular filtration or other interfering factors remains speculative. © 2012 John Wiley & Sons, Ltd.
The effect of fetal congenital heart disease on in utero urine production rate
Authors: Xie Jing‐Xian , Lv Guo‐Rong , Chen Qiu‐Yue , Hou Min
Published: April 2012

Objectives

To evaluate the influence of congenital heart disease (CHD) or congestive heart failure (CHF) on fetal urine production rate (UPR) and to establish normal reference intervals.

Methods

A cross‐sectional study was performed on normal fetuses (n = 314) and on fetuses with CHD (n = 49). CHD cases were divided into groups on the basis of heart function as defined by Huhta score: with CHF (n = 11) and without CHF (n = 38). Fetal bladder volume was measured by two‐dimensional as well as three‐dimensional ultrasound with the Virtual Organ Computer‐aided Analysis technique.

Results

In normal fetuses, UPR increased with gestational age from a mean value of 4.5 mL/h at 21 weeks to 66.5 mL/h at 40 weeks. There were no significant differences in UPR between CHD cases without CHF and controls (P = 0.581). However, fetuses with CHF had decreased UPR values (Controls vs. CHF, P = 0.007) compared with the controls. The interobserver and intraobserver variability for assessment of UPR was better using three‐dimensional rather than two‐dimensional US.

Conclusions

Fetal UPR can be reproducibly measured by the Virtual Organ Computer‐aided Analysis technique. It appears that heart function, rather than CHD, affects fetal UPR. Fetal UPR may therefore be an additional indicator of CHF. © 2012 John Wiley & Sons, Ltd.
Usefulness of thoracic CT to diagnose tuberculosis disease in patients younger than 4 years of age
Authors: Garrido J. Batlles , Alías Hernández I. , Bonillo Perales A. , Rubí Ruiz T. , González Jiménez Y. , González‐Ripoll Garzón M. , Moriana Maldonado J. , González de Rojas J.D. , Martínez Lirola M. , Fornovi Vives J.J.
Published: April 2012

Background

There is controversy over the need of using thoracic CT (TCT) systematically for differentiating disease from tuberculosis infection in young children. This distinction is important when making a diagnosis of TB as the treatment changes from a single drug to a multidurug regimen with reported side‐effects.

Aim

To determine the usefulness of using TCT to diagnose pulmonary tuberculosis (PTB) in patients younger than 4 years of age who have TB infection (IBI).

Materials and Methods

After the simultaneous detection of four cases of PTB in children who attended the same class, a study on the contact among workers and children was carried out. One hundred sixteen children younger than 4 years and 20 adults were included. The tuberculin skin test (TST) was performed on all of them. CHEST XR (CXR) and TCT were performed on children with positive TST and three samples of gastric acid were taken. CXR and sputum testing were performed on adults with positive TST.

Results

TST was positive in 28 children (24.1%). In 92.8% of children with positive TST and normal CXR, TCT showed features compatible with PTB. Out of the 28 children with positive TST, 27 (96.4%) were diagnosed with PTB and only one with latent TBI (4%).

Conclusions

In children younger than 4‐year old with positive TST and normal CXR, it would be advisable to perform a TCT since the findings could change the diagnosis from TBI to TB disease. Pediatr Pulmonol. 2012. 47:895–902. © 2012 Wiley Periodicals, Inc.
Ursolic Acid Inhibits Acid Sphingomyelinase in Intestinal Cells
Authors: Zhang Ping , Cheng Yajun , Duan Rui‐Dong
Published: April 2012

Ursolic acid (UA) has antiinflammatory and anticancer effects on mammalian cells. Increase in acid sphingomyelinase (SMase) is associated with several inflammatory diseases including inflammatory bowel diseases. The enzyme has become a target for drug discovery. The present study examined the roles of UA on acid SMase in intestinal cells. We found that UA specifically inhibited acid SMase activity in both human colon cancer Caco‐2 cells and rat nontransformed IEC‐6 intestinal cells in a dose‐dependent manner, with 50% inhibition occurred at 30 μM for Caco‐2 cells and less than 20 μM for IEC‐6 cells. In comparison with some chemicals known to inhibit acid SMase, UA appeared most effective. The decreased acid SMase activity was not associated with significant accumulation of cellular sphingomyelin but significant increase in phosphatidylcholine, the donor of choline for sphingomyelin synthesis. Western blot analysis showed a decreased enzyme levels in the cells after UA stimulation, but real time quantitative polymerase chain reaction (qPCR) failed to show a parallel reduction of acid SMase mRNA after UA stimulation. Finally, UA had no direct effect on acid SMase activity in cell‐free extracts. In conclusion, UA has inhibitory effects on acid SMase synthesis and the effect occurs presumably at posttranslational levels. Copyright © 2012 John Wiley & Sons, Ltd.
Antihyperlipidemic Components of Cassia auriculata Aerial Parts: Identification Through In Vitro Studies
Authors: Habtemariam Solomon
Published: April 2012

Cassia auriculata (Caesalpiniaceae) is a common Asian beverage and medicinal plant widely used in tradition medicine for diabetes, hyperlipidemia and various other disease conditions. Previous studies on crude extracts of C. auriculata have documented the scientific basis for some of its traditional medicinal uses. The present study investigates the antilipase activity of the ethanol extract of the aerial parts along with the previously isolated compounds (kaempferol‐3‐O‐rutinoside, rutin, kaempferol, quercetin and luteolin). The crude extract displayed inhibitory activity against pancreatic lipase with IC50 of 6.0 ± 1.0 µg/mL. The most active antilipase compound was kaempferol‐3‐O‐rutinoside with IC50 value (2.9 ± 0.50 μM) only about twice weaker than the standard antilipase drug, orlistat (IC50 = 1.45 ± 0.26 μM). Luteolin, quercetin and rutin were found to be weak pancreatic lipase inhibitors (IC50 over 100 μM), whereas kaempferol showed no activity up to 250 μM. The antihyperlipidemic effect of C. auriculata could be attributed to direct lipase inhibitory effect of the plant constituents. Copyright © 2012 John Wiley & Sons, Ltd.
Introducing proxy zero‐knowledge proof and utilization in anonymous credential systems
Authors: Jannati Hoda , Salmasizadeh Mahmoud , Mohajeri Javad , Moradi Amir
Published: April 2012

In pseudonym systems, users by means of pseudonyms anonymously interact with organizations to obtain credentials. The credential scheme constructed by Lysyanskaya and Camenisch is among the most complete credential systems, in which “all‐or‐nothing” sharing scheme is used to prevent users sharing their credentials. If a user cannot directly show a credential issued by an organization, she or he has to give her or his own secret key to someone else as a proxy; afterward, the proxy can show the credential on behalf of the user. Thus, according to the all‐or‐nothing property of the system, having the user's secret key, the proxy can use all credentials of the user for itself. To solve this problem, in this paper, we present proxy zero‐knowledge proof and utilize it in Lysyanskaya and Camenisch anonymous credential system. In our proposed system, instead of giving the secret key to the proxy, the user generates a proxy key based on the desired credential particularly for the proxy. Therefore, the proxy neither is the owner of the user's credential nor uses his or her other credentials. Copyright © 2012 John Wiley & Sons, Ltd.
Anti‐wear properties of amorphous a‐C:H and a‐C:N:H carbon coatings deposited on polycarbonate
Authors: Slawomir Zimowski , Rakowski Wieslaw Andrzej , Jonas Stanislawa
Published: April 2012

In this study, we investigate the tribological properties of amorphous hydrogenated (a‐C:H) and nitrogenated (a‐C:N:H) carbon coatings deposited on polycarbonate substrates (PC). The a‐C:H and a‐C:N:H coatings of 700‐nm thickness were deposited by radio frequency chemical vapour deposition method (13.56 MHz, 300 W). The chemical composition of the coatings was determined by X‐ray photoelectron spectroscopy and their structure with the use of Fourier transform infrared spectroscopy spectroscopy. A surface roughness was measured by contact method. It was found that the nitrogenated a‐C:N:H coatings have much lower surface roughness in comparison with hydrogenated a‐C:H one. All examined coatings showed very good adhesion to PC substrate in the scratch test. Tribological properties were investigated with the use of ball‐on‐disc tribometer in the contact with 100Cr6 steel ball. The pure PC exhibited higher coefficient of friction (0.38) as compared to those with the coatings. The lowest value of friction coefficient (around 0.17) was found for a‐C:H coating. The wear resistance of the amorphous carbon/substrate system is about 10 times higher than that of PC substrate. Copyright © 2012 John Wiley & Sons, Ltd.
Simultaneous detection and localization of secondary ions and electrons from single large cluster impacts
Authors: Eller M. J. , Verkhoturov S. V. , Fernandez‐Lima F. A. , DeBord J. D. , Schweikert E. A. , Della‐Negra S.
Published: April 2012

The use of large cluster primary ions (e.g. C60, Au400) in secondary ion mass spectrometry has become prevalent in recent years due to their enhanced emission of secondary ions, in particular, molecular ions (MW ≤ 1500 Da). The co‐emission of electrons with SIs was investigated per projectile impact. It has been found that SI and electrons yields increased with increasing projectile energy and size. The use of the emitted electrons from impacts of C60 for localization has been demonstrated for cholesterol deposited on a copper grid. The instrumentation, methodologies, and results from these experiments are presented. Copyright © 2012 John Wiley & Sons, Ltd.
Effect of post‐synthesis heat‐treatment on the structural and dielectric features of nano‐sized BaTiO3 powders
Authors: Min Boram , Moon S.‐M. , Cho N.‐H.
Published: April 2012

The effect of post‐synthesis heat‐treatment on the structural evolution of nano‐sized BaTiO3 powders prepared by the hydrothermal synthesis method was investigated. The tetragonal fraction of the as‐prepared powders was found to be approximately 19% and those of the powders heat‐treated at 600, 800 and 1000 °C for 1 h were 21, 56 and 90%, respectively. The relative dielectric constants also increased with increasing heat‐treatment temperature. In the case of the as‐prepared nano‐sized BaTiO3 powders and those heat‐treated at 600 °C, a considerable fraction of cubic‐like lattice was present near the surface; the lattice spacing along the a1‐axis was nearly constant, while that along the a3‐axis increased with increasing distance from the surface to the core region of the powder. On the other hand, for the powders heat‐treated at 800 and 1000 °C, even the shell region of the powders mostly consisted of the tetragonal‐like phase, which indicates that there is little size effect near the surface of the powders. Copyright © 2012 John Wiley & Sons, Ltd.
Characterization of PEG‐conjugated gold nanoparticles using a statistical analysis on time‐of‐flight SIMS images
Authors: Shon Hyun Kyong , Kim Soo Jin , Park Hyun Min , Moon Dae Won , Song Nam Woong , Lee Tae Geol
Published: April 2012

Gold nanoparticles (AuNPs) and poly(ethylene glycol) (PEG) are known to be safe, biocompatible materials. In this study, AuNPs were conjugated with PEG ligands, and the suspensions of AuNPs with and without free PEG ligands were characterized using UV‐visible spectroscopy, hydrodynamic size measurement, and time‐of‐flight SIMS (ToF‐SIMS) imaging analysis. The two AuNPs solutions were each dropped onto a hydrophilic surface (bare Si wafer) and a hydrophobic surface (a plasma‐polymerized cyclohexane‐coated Si wafer), then dried to produce self‐aggregated micropatterns, from which ToF‐SIMS images were obtained. From these ToF‐SIMS images, we calculated the Pearson product–moment correlation coefficient (PMCC) of the AuNPs and PEG intensities to quantitatively measure the coexistence of both materials in the solution. Good coexistence between AuNPs and PEG ligands was obtained only from the sample film prepared by dropping the suspension of PEG‐conjugated AuNPs without free ligands onto a hydrophobic surface. The degrees of coexistence (i.e. PMCC value) seem to correlate with the amount of free PEG ligands in suspension to affect the stability of organic conjugated nanoparticles in solution. In addition, it was found that minimal interaction between the conjugated ligands and the substrate used for the sample film preparation led to an optimum PMCC statistical analysis. Our results lead us to believe that this new approach could simplify the method by which to quantitatively study the degrees of coexistence between nanoparticles and ligands, the amount of free ligands, and the stability of ligand‐conjugated nanoparticles in suspension. Copyright © 2012 John Wiley & Sons, Ltd.
Phase analysis and thermoelectric properties of Zn1−xMxO (M= Al, Ga) samples
Authors: Jung Kwang‐Hee , Choi Soon‐Mok , Lim Chang‐Hyun , Seo Won‐Seon , Park Hyung‐Ho
Published: April 2012

Thermoelectric oxides have been regarded as promising materials for power generation especially at high temperature. Among them, ZnO systems have been reported as useful n‐type thermoelectrics because of high Seebeck coefficients and electrical conductivities at high temperature. In this study, we investigated polycrystalline ZnO systems doped with different donor ions Al3+ and Ga3+. We investigated reasons of different solution limits and secondary phases and microstructures between these two donor‐doped cases. Thermoelectric properties also showed different tendency between Al3+‐ and Ga3+‐doped ZnO systems because of their different structural properties. As a result, a maximum power factor value 9.18 × 10−4 W/mK2 at 1050 K was obtained in Zn0.98Ga0.02O composition. Copyright © 2012 John Wiley & Sons, Ltd.
Microanalysis of blue pigments from the Ptolemaic temple of Hathor (Thebes), Upper Egypt: a case study
Authors: Marey Mahmoud Hussein H.
Published: April 2012

The aim of the present work was to characterize blue pigment samples collected from the Ptolemaic temple of Hathor (Thebes), the western bank of Luxor, Upper Egypt. The characterization of the examined pigments was carried out by means of optical microscopy, scanning electron microscopy equipped with an energy dispersive X‐ray detector, micro X‐ray fluorescence spectrometry and Fourier transform infrared spectroscopy. On the basis of the chemical composition and microstructure of the samples, the blue pigments were identified as Egyptian blue (cuprorivaite, CaCuSi4O10). Moreover, the micro X‐ray fluorescence analysis revealed significant quantities of lead in the glass phase suggesting that a leaded bronze scrap was used to produce the pigment. The optical examination of the paint layers showed that the pigments were applied on a thin layer consisting of gypsum (CaSO4∙2H2O) and dolomite (CaMg(CO3)2). In addition, some pigment samples showed discoloration mainly in the form of green and black hues. The obtained results helped in improving our knowledge about some painting materials used during the Ptolemaic era of ancient Egypt. Copyright © 2012 John Wiley & Sons, Ltd.
Preparation and characterization challenges to understanding environmental and biological impacts of ceria nanoparticles
Authors: Karakoti A. S. , Munusamy P. , Hostetler K. , Kodali V. , Kuchibhatla S. , Orr G. , Pounds J. G. , Teeguarden J. G. , Thrall B. D. , Baer D. R.
Published: April 2012

Increasingly, it is recognized that understanding and predicting nanoparticle behavior are often limited by the reliability and reproducibility of the production methods as well as the extent to which they are adequately characterized. Two examples are used to demonstrate how sample preparation methods and processing history may significantly impact particle behavior: (1) an examination of cerium oxide (ceria) particles reported in the literature in relation to the biological responses observed and (2) observations showing the influence of synthesis details on the aging of ceria nanoparticles. Examining data from the literature for ceria nanoparticles suggests that thermal history is one factor that has a strong influence on biological impact. Thermal processing may alter many physicochemical properties of the particles, including density, crystal structure, and the presence of surface contamination. However, these properties may not be sufficiently recorded or reported to determine the ultimate source of an observed impact. A second example shows the types of difficulties that can be encountered in efforts to apply a well‐studied synthesis route to producing well‐defined particles for biological studies. These examples and others further highlight the importance of characterizing particles thoroughly and recording details of particle processing and history that too often are underreported. Copyright © 2012 John Wiley & Sons, Ltd.
EMUSIM: an integrated emulation and simulation environment for modeling, evaluation, and validation of performance of Cloud computing applications
Authors: Calheiros Rodrigo N. , Netto Marco A.S. , De Rose César A.F. , Buyya Rajkumar
Published: April 2012

Cloud computing allows the deployment and delivery of application services for users worldwide. Software as a Service providers with limited upfront budget can take advantage of Cloud computing and lease the required capacity in a pay‐as‐you‐go basis, which also enables flexible and dynamic resource allocation according to service demand. One key challenge potential Cloud customers have before renting resources is to know how their services will behave in a set of resources and the costs involved when growing and shrinking their resource pool. Most of the studies in this area rely on simulation‐based experiments, which consider simplified modeling of applications and computing environment. In order to better predict service's behavior on Cloud platforms, we developed an integrated architecture that is based on both simulation and emulation. The proposed architecture, named EMUSIM, automatically extracts information from application behavior via emulation and then uses this information to generate the corresponding simulation model. We performed experiments using an image processing application as a case study and found that EMUSIM was able to accurately model such application via emulation and use the model to supply information about its potential performance in a Cloud provider. We also discuss our experience using EMUSIM for deploying applications in a real public Cloud provider. EMUSIM is based on an open source software stack and therefore it can be extended for analysis behavior of several other applications. Copyright © 2012 John Wiley & Sons, Ltd.
FiRePat—Finding Regulatory Patterns between sRNAs and Genes
Authors: Mohorianu Irina , Lopez‐Gomollon Sara , Schwach Frank , Dalmay Tamas , Moulton Vincent
Published: April 2012

Small RNAs are regulatory RNA fragments which, through RNA silencing, can regulate the expression of genes. Because sRNAs are negative regulators it is generally assumed that expression profiles of sRNAs and their targets are negatively correlated. Recently, examples of positive correlation between the expression of sRNAs and their targets have been discovered. At the moment, it is not known how many sRNA‐target pairs are positively and negatively correlated, and it is also not clear in what situations (e.g., under which treatments) any of these correlations can be observed. To determine this, one of the first steps is to develop tools to carry out a genome wide characterization of covariation of expression levels of sRNAs and genes. We present FiRePat—Finding Regulatory Patterns—an unsupervised data mining tool applicable to large datasets, typically produced by high throughput sequencing of sRNAs and mRNAs or microarray experiments, that detects sRNA‐gene pairs with correlated expression levels. The method consists of three steps: first, we select differentially expressed sRNAs and genes; second, we compute the correlation between sRNA and gene series for all possible sRNA–gene pairs; and third, we cluster the sRNA or gene expression series, simultaneously inducing clusters in the other series. Potential uses of FiRePat are presented using publicly available sRNA and mRNA datasets for both plants and animals. The standard output of FiRePat, a list of correlated pairs formed with sRNAs and mRNAs, can be used to investigate the cause and consequences of the respective expression patterns. © 2012 Wiley Periodicals, Inc.

This article is categorized under:

Algorithmic Development > Biological Data Mining
Effect of Chronic Anal Fissure Components on Isosorbide Dinitrate Treatment
Authors: Arslan K. , Erenoğlu B. , Doğru O. , Kökçam S. , Turan E. , Atay A.
Published: April 2012

Background

Chronic anal fissure is diagnosed in the presence of persistent symptoms: The classic triad includes a linear mucosal tear exposing the internal sphincter fibers, hypertrophied anal papilla, and a sentinel skin tag. Thus, chronic anal fissure can be divided into three components: the fissure itself; hypertrophied anal papilla; the sentinel skin tag. Not every chronic anal fissure has all three components; some have two components, and others present with only a persistent fissure. The success rate of medical treatment for chronic anal fissure is reported as 42–86 %. In this study, we intended to observe the effect of said components on healing with isosorbide dinitrate treatment.

Methods

A total of 105 patients with chronic anal fissures were admitted and were divided into three groups. Patients in group I had a single component (only the fissure with a linear mucosal tear exposing the internal sphincter fibers); group II had two components (skin tag or hypertrophied papilla in addition to the fissure); group III had all three components (fissure, skin tag, hypertrophied papilla). Isosorbide dinitrate 0.25 % was applied three times a day.

Results

The success rates in the study groups were 93, 74, and 64 %, respectively. The success rate was significantly higher for group I than for groups II and III.

Conclusions

Chronic anal fissure components should be considered when evaluating the success rates of studies reporting the results of various medical treatments. The number of components seems to be an important factor that affects the results of isosorbide dinitrate treatment.
Low Docosahexaenoic Acid Content in Plasma Phospholipids is Associated with Increased Non‐alcoholic Fatty Liver Disease in China
Authors: Zheng Ju‐Sheng , Xu Amei , Huang Tao , Yu Xiaomei , Li Duo
Published: April 2012

A large proportion of the Chinese population is now at risk of non‐alcoholic fatty liver disease (NAFLD). We aimed to investigate the relationship between plasma phospholipids (PL) fatty acids and the risk of NAFLD. One hundred NAFLD patients and 100 healthy subjects were recruited in Hangzhou, China. Plasma PL and selected biochemical and hematological parameters were analyzed by using standard methods. Stepwise logistic regression was used to identify independent risk factors of NAFLD. Plasma PL total saturated fatty acid (SFA), C20:3n‐6, serum alanine aminotransferase, high‐density lipoprotein cholesterol, and body mass index were independent risk factors of NAFLD. The risk of NAFLD was significantly increased with higher quartiles of plasma PL total SFA (P for trend = 0.028) and C20:3n‐6 (P for trend <0.001); plasma PL docosahexaenoic acid (C22:6n‐3) was significantly lower in NAFLD patients than in controls (P = 0.032) and the OR of NAFLD in the highest quartile of C22:6n‐3 was 0.41 (95 % CI = 0.17–0.97) compared with the lowest quartile. In conclusion, plasma PL total SFA and C20:3n‐6 are positively correlated with the risk of NAFLD, while C22:6n‐3 is negatively correlated with the risk of NAFLD.