bluuebunny/crossref_metadata_2025 huggingface dataset:
Breaking Tor anonymity with game theory and data mining
Authors: Wagner Cynthia , Wagener Gerard , State Radu , Dulaunoy Alexandre , Engel Thomas
Published: July 2011

Attacking anonymous communication networks is very tempting, and many types of attacks have already been observed. In the case for Tor, a widely used anonymous overlay network is considered. Despite the deployment of several protection mechanisms, an attack originated by just one rogue exit node is proposed. The attack is composed of two elements. The first is an active tag injection scheme. The malicious exit node injects image tags into all HTTP replies, which will be cached for upcoming requests and allow different users to be distinguished. The second element is an inference attack that leverages a semi‐supervised learning algorithm to reconstruct browsing sessions. Captured traffic flows are clustered into sessions, such that one session is most probably associated to a specific user. The clustering algorithm uses HTTP headers and logical dependencies encountered in a browsing session. A prototype has been implemented and its performance evaluated on the Tor network. The article also describes several countermeasures and advanced attacks, modeled in a game theoretical framework, and their effectiveness assessed with reference to the Nash equilibrium. Copyright © 2011 John Wiley & Sons, Ltd.
Theoretical analysis of the shape evolution of crystals grown by pulling
Authors: Zhang Lunyong , Zuo Hongbo , Sun Jianfei , Wang Xiaohong , Han Jiecai , Xing Dawei
Published: July 2011

This paper proposes a geometric model for crystal growth by pulling. On the basis of the model, effects of the growth processes on the evolution of crystal shape were studied. Besides some effects already adopted in practice to control the crystal diameter, our results revealed several novel effects: a crystal grown under fixed process parameters could grow with a self‐stabilized diameter after shoulder‐expanding; decreasing the convex degree of solid liquid interface would enhance the increasing rate of crystal diameter or reduce the decreasing rate of crystal diameter. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Maternal stress induces adult reduced REM sleep and melatonin level
Authors: Feng Pingfu , Hu Yufen , Vurbic Drina , Guo Yang
Published: July 2011

We have previously reported that neonatal maternal deprivation (MD) resulted in a decrease of total sleep and an increase of orexin A in adult rats. Now, we characterized features of sleep, activity, and melatonin levels in rats neonatally treated with MD and control (MC) procedures. Adult male Sprague–Dawley rats were treated with either MD or MC procedures for 10 days starting at postnatal day 4. At 3 months of age, sleep was recorded for 48 h in one set of MD and MC rats, while another set of MD and MC rats was measured for locomotor activity (under LD = 12:12). Melatonin levels in the blood, pineal gland, and hypothalamus were measured as well as clock protein level in the hypothalamus. Compared to the MC rats, REM sleep in the MD rats was significantly reduced in the light periods but not in the dark periods. Both quiet wake and total wake in the MD rats were significantly increased during the light period compared to the MC rats. The weight of the pineal gland of the MD rats was significantly smaller than in MC rats. Melatonin levels of the MD group were significantly reduced in the pineal gland and hypothalamus compared to the MC group. No significant difference was identified between groups in the expression of the clock protein in the hypothalamus. Neonatal MD resulted in reduced REM sleep and melatonin levels, without changes of circadian cycle of locomotor activity and levels of clock protein. © 2011 Wiley Periodicals, Inc. Develop Neurobiol 72: 677–687, 2012
Normal late ventricular potentials in hospitalized patients with eating disorders
Authors: Nussinovitch Moshe , Gur Eitan , Kaminer Keren , Volovitz Benjamin , Nussinovitch Naomi , Nussinovitch Udi
Published: July 2011

Objective:

Eating disorders, in particular anorexia nervosa (AN), are associated with cardiovascular complications and risk of arrhythmias. In a recent published study, it was found that patients with eating disorders, especially those affected by bulimia nervosa (BN) and a history of AN have abnormal late ventricular potentials (LPs). LPs are electrocardiographic markers used in detecting abnormal depolarization and increased risk of arrhythmias. Given the paucity of knowledge regarding the affects of eating disorders on cardiac depolarization, our aim was to further explore LPs in patients with eating disorders.

Method:

The study group included 30 hospitalized patients with eating disorders (14 with AN, 10 with BN with no history of AN, and 6 with BN and history of AN). Signal averaged electrocardiography was conducted on all patients usingthe Frank corrected orthogonal lead system.

Results:

No patient with either eating disorder tested positive for LPs.

Discussion:

Hospitalized patients with eating disorders, medically monitored and treated for several weeks, had normal serum electrolytes, started to normalize their weight, and did not appear to be prone to arrhythmias associated with abnormal depolarization. The prognostic significance of LPs in risk stratification of patients with eating disorders should be further evaluated by large cohort studies and longer follow‐up studies. © 2011 by Wiley Periodicals, Inc. (Int J Eat Disord 2011;45:900–904)
2‐(1‐Acetyl‐2‐oxopropyl)‐5,10,15,20‐tetraphenylporphyrin and Its Transition‐Metal Complexes
Authors: He Hongshan , Dubey Mukul , Zhong Yihan , Shrestha Maheshwar , Sykes Andrew G.
Published: July 2011

The 2‐(1‐acetyl‐2‐oxopropyl)‐5,10,15,20‐tetraphenylporphyrin free base (H2TPP‐AOP) and its transition‐metal complexes (MTPP‐AOP, M = Cu2+, Zn2+) have been synthesized. Single‐crystal X‐ray diffraction analysis revealed that the 1‐acetyl‐2‐oxopropyl (AOP) group is attached to a β‐pyrrolic position through the methylene group. The mean plane of the AOP is almost perpendicular to the porphyrin ring. The zinc(II) complex crystallizes as a five‐coordinate species with one methanol/water solvate in the axial position, whereas the copper(II) complex is four‐coordinate. These compounds exhibit strong absorption in the UV and visible regions. The fluorescence lifetimes are 1.85 and 8.0 ns for the free base and zinc(II) complex, respectively. Density functional calculations indicate that these porphyrins are energetically suitable for electron injection from their lowest‐unoccupied molecular orbitals to the conduction band of the titanium dioxide semiconductor. However, the energy conversion efficiencies of the three porphyrin‐sensitized solar cells are low, that is, 0.14, 0.015 and 0.021 % for ZnTPP‐AOP, CuTPP‐AOP and H2TPP‐AOP, respectively. The poor photovoltaic performance is ascribed to the low dye‐loading of these porphyrins on the titanium dioxide surface. The neighbouring phenyl groups exert sufficient steric hindrance on the AOP to limit its binding to the TiO2 semiconductor.
Lithium Complex of an Abnormal Carbene
Authors: Jana Anukul , Azhakar Ramachandran , Tavčar Gašper , Roesky Herbert W. , Objartel Ina , Stalke Dietmar
Published: July 2011

A lithium complex of an abnormal carbene with the composition [H3BC{{N(2,6‐iPr2C6H3)}2CHCLi(THF)3}] was synthesized by the lithiation reaction of the N‐heterocyclic carbene borane adduct {IPr·BH3, IPr = [C{[N(2,6‐iPr2C6H3)]CH}2] (1)} with nBuLi. The lithiated species was proven by NMR spectroscopy and unambiguously established by single‐crystal X‐ray structural analysis.
Factors Associated with Emotional Well‐being in Primary and Secondary Caregivers of Patients with Eating Disorders
Authors: Sepúlveda Ana R. , Graell Montserrat , Berbel Enrique , Anastasiadou Dimitra , Botella Juan , Carrobles José A. , Morandé Gonzalo
Published: July 2011

The aim of this study was to examine and identify the psychological, clinical and sociodemographic factors associated with emotional well‐being by type of caregiver. A cross‐sectional study was conducted among 185 primary caregivers and 92 secondary caregivers of patients with an eating disorder using the Hospital Anxiety and Depression Scale, the Experience of Caregiving Inventory and the Eating Disorders Symptom Impact Scale. According to a multiple regression analysis, a total of four models were obtained accounting for 42%–47% of the variance in emotional well‐being. The variable that accounted for most of the variance of emotional well‐being in three of the models was the impact of nutrition. Improving aspects of the relationships with the patients reduced anxiety and depression levels in primary caregivers. Similarly, a positive personal experience reduced depression in secondary caregivers. A higher education level was associated with decreased anxiety levels in both types of caregivers. Specific family interventions including both types of caregivers may be useful for providing emotional and adaptive personal coping skills. Copyright © 2011 John Wiley & Sons, Ltd and Eating Disorders Association.
Components of Shame and Eating Disturbance Among Clinical and Non‐clinical Populations
Authors: Doran Jackie , Lewis Christopher Alan
Published: July 2011

Objective

To examine the association between components of shame (characterological, behavioural and bodily) and eating disturbance.

Method

This was a cross sectional study of 859 female and 256 male participants from the general population [non‐clinical (NCP)] and 167 female participants from an eating disordered population [clinical (CP)] completing the Experience of Shame Scale. The NCP samples also completed the Eating Attitudes Test‐26, and the CP samples completed the Eating Disorder Risk Composite of the Eating Disorder Inventory‐3. Participants were recruited via schools/colleges, eating disorder charities and the Internet.

Results

Bodily and characterological shame were independently predictive of eating disturbance in female NCP samples (both, p < .001); bodily shame was uniquely predictive of eating disturbance for the male NCP (p < .05) and female CP samples (p < .001).

Conclusion

The aetiology of eating disturbance may be different for male and female NCP samples. The male NCP and the female CP samples displayed a similar pathway to eating disturbance. It is important to acknowledge the different components of shame associated with eating disturbance in different populations. Copyright © 2011 John Wiley & Sons, Ltd and Eating Disorders Association.
An efficient discontinuous Galerkin method for aeroacoustic propagation
Authors: Della Ratta Rinaldi R. , Iob A. , Arina R.
Published: July 2011

An efficient discontinuous Galerkin formulation is applied to the solution of the linearized Euler equations and the acoustic perturbation equations for the simulation of aeroacoustic propagation in two‐dimensional and axisymmetric problems, with triangular and quadrilateral elements. To improve computational efficiency, a new strategy of variable interpolation order is proposed in addition to a quadrature‐free approach and parallel implementation. Moreover, an accurate wall boundary condition is formulated on the basis of the solution of the Riemann problem for a reflective wall. Time discretization is based on a low dissipation formulation of a fourth‐order, low storage Runge–Kutta scheme. Along the far‐field boundaries a perfectly matched layer boundary condition is used. For the far‐field computations, the integral formulation of Ffowcs Williams and Hawkings is coupled with the near‐field solver. The efficiency and accuracy of the proposed variable order formulation is assessed for realistic geometries, namely sound propagation around a high‐lift airfoil and the Munt problem. Copyright © 2011 John Wiley & Sons, Ltd.
Capillary blood flow around microglial somata determines dynamics of microglial processes in ischemic conditions
Authors: Masuda Tadashi , Croom Deborah , Hida Hideki , Kirov Sergei A.
Published: July 2011

Microglia are the resident immune cells in the brain. Under normal conditions, resting ramified microglia constantly extend and retract fine processes while performing immunological surveillance. In ischemia, microglia become activated as demonstrated by morphological changes during deramification leading to transformation from ramified to amoeboid form. In vivo two‐photon microscopy of enhanced green fluorescent protein (EGFP)‐expressing microglia in mouse neocortex was used to examine microglial dynamics during the early periods of focal and global ischemia. A penumbra‐like “area‐at‐risk” surrounded by a square‐shaped area of severely hypoperfused tissue was created by laser‐induced photothrombosis. The dynamics of microglial processes in the area‐at‐risk was strongly correlated with capillary blood flow (BF) measured within 10 μm of microglial somata. Changes in BF around distal microglial processes (>30 μm from somata) had no effect on microglial dynamics. A severe reduction of capillary BF near somata by 84% ± 6% resulted in initiation of microglial deramification, suggesting activation. A moderate decrease in BF near somata by 22% ± 5% or increase by 87% ± 10%, reflecting a redistribution of capillary BF, had no effect on microglial morphology. Complete BF loss during cardiac arrest (CA) or transient bilateral common carotid artery occlusion (BCCAO) entirely stalled all microglial processes without structural changes. Reperfusion after BCCAO induced recovery of microglial dynamics to preocclusion values. These findings suggest that during ischemia, the severe drop in BF around microglial somata coincides with morphological activation. However, this activation requires some residual BF, because complete perfusion loss (as during BCCAO and CA) did not support microglial deramification. © 2011 Wiley‐Liss, Inc.
Hepatitis C virus induces interferon-λ and interferon-stimulated genes in primary liver cultures
Authors: Marukian Svetlana , Andrus Linda , Sheahan Timothy P. , Jones Christopher T. , Charles Edgar D. , Ploss Alexander , Rice Charles M. , Dustin Lynn B.
Published: July 2011

Hepatitis C virus (HCV) replication in primary liver cells is less robust than that in hepatoma cell lines, suggesting that innate antiviral mechanisms in primary cells may limit HCV replication or spread. Here we analyzed the expression of 47 genes associated with interferon (IFN) induction and signaling following HCV infection of primary human fetal liver cell (HFLC) cultures from 18 different donors. We report that cell culture-produced HCV (HCVcc) induced expression of Type III (λ) IFNs and of IFN-stimulated genes (ISGs). Little expression of Type I IFNs was detected. Levels of IFNλ and ISG induction varied among donors and, often, between adapted and nonadapted HCV chimeric constructs. Higher levels of viral replication were associated with greater induction of ISGs and of λ IFNs. Gene induction was dependent on HCV replication, as ultraviolet light-inactivated virus was not stimulatory and an antiviral drug, 2′-C-methyladenosine, reduced induction of λ IFNs and ISGs. The level of IFNλ protein induced was sufficient to inhibit HCVcc infection of naïve cultures.

Conclusion:

Together, these results indicate that despite its reported abilities to blunt the induction of an IFN response, HCV infection is capable of inducing antiviral cytokines and pathways in primary liver cell cultures. Induction of ISGs and λ IFNs may limit the growth and spread of HCV in primary cell cultures and in the infected liver. HCV infection of HFLC may provide a useful model for the study of gene induction by HCV

in vivo

. (Hepatology 2011;)
Feasibility of conducting a randomized control trial for liver cancer screening: Is a randomized controlled trial for liver cancer screening feasible or still needed?
Authors: Poustchi Hossein , Farrell Geoffrey C. , Strasser Simone I. , Lee Alice U. , McCaughan Geoffrey W. , George Jacob
Published: July 2011

Screening for hepatocellular carcinoma (HCC) is commonly practiced and recommended in published guidelines, but evidence for its efficacy has been controversial. We tested the feasibility of conducting a randomized controlled trial (RCT) of HCC surveillance in patients with cirrhosis and followed up those offered screening to detect clinical outcomes. Participation was offered to patients with cirrhosis attending liver clinics at three university hospitals. Following discussion, patients received a decision aid (DA) that outlined the risks and benefits of surveillance. The proposed screening program comprised ultrasonography 6-monthly and serum alpha-fetoprotein every 3 months. We envisaged five groups of patients: those who agreed to randomization, those choosing nonrandomized screening, those wanting continuation of usual care, those who were undecided, and those refusing participation. Among 205 patients, 204 (99.5%) declined randomization. Of these, 181 (88%) elected for a nonrandomized screening program, 10% chose usual care (which typically included

ad hoc

screening), and two were undecided. Among 176 patients fluent in English communication skills, 160 (91%) preferred nonrandomized screening compared with 22/29 (76%) patients needing an interpreter (

P

< 0.026). Of 173 patients in nonrandomized screening followed up for a mean 13.5 ± 6.04 months, three developed HCC, two died from nonliver-related causes, and one underwent liver transplantation for liver failure. Eighteen of 21 patients in “usual care” received

ad hoc

screening. A simultaneous survey on the quality of the DA showed that the majority of participants believed that the information provided was unbiased.

Conclusion:

Although an RCT is theoretically ideal for determining the efficacy, efficiency, and cost-effectiveness of HCC screening, informed patients prefer surveillance. A randomized study of HCC screening is not feasible when informed consent is imparted. (Hepatology 2011;)
Cannabis use and sensorimotor gating in patients with schizophrenia and healthy controls
Authors: Scholes‐Balog Kirsty E. , Martin‐Iverson Mathew T.
Published: July 2011

Objective

Schizophrenia patients and healthy cannabis users show different attention‐dependant alterations in prepulse inhibition (PPI). It is of interest then to examine PPI in patients with schizophrenia who use cannabis, given the hypothesized association between cannabis use and schizophrenia.

Methods

Prepulse inhibition was measured in 34 healthy cannabis users, 32 healthy non‐using controls, 20 patients with schizophrenia who were current cannabis users, and 44 non‐using patients with schizophrenia. PPI was measured across a range of startling stimulus intensities, during two attention set conditions. Curves of best fit were fitted to the startle magnitudes, across the stimulus intensities. A number of reflex parameters were extracted from these logistic functions.

Results

Similar to healthy cannabis users, cannabis‐using patients showed altered PPI of Threshold, only when instructed to sustain attention to the auditory stimuli. Conversely, non‐using patients with schizophrenia showed reduced PP of RMAX only when instructed to ignore the auditory stimuli.

Conclusion

Cannabis use in patients with schizophrenia is associated with a similar pattern of attention‐dependant alterations in PPI to that observed in healthy cannabis users. This is different to those observed in patients with schizophrenia who do not use cannabis and may be as a result of a dysfunction of sustained attention. Copyright © 2011 John Wiley & Sons, Ltd.
Patterns, puzzles and people: implementing hydrologic synthesis
Authors: Thompson Sally E. , Harman C. J. , Schumer R. , Wilson J. S. , Basu N. B. , Brooks P. D. , Donner S. D. , Hassan M. A. , Packman A. I. , Rao P. S. C. , Troch P. A. , Sivapalan M.
Published: July 2011

There have been several calls made for hydrologic synthesis research: namely activities which unify diverse data sources across sites, scales and disciplines to uncover new connections and to promote a holistic understanding of water science. This paper draws on the NSF‐funded Hydrological Synthesis Project (HSP) run by the University of Illinois at Urbana‐Champaign to elucidate mechanisms, benefits and challenges of implementing hydrologic synthesis research from the perspectives of participants in a pilot research study. Two broadly different mechanisms of implementing synthesis were adopted in the HSP: 6‐week Summer Institutes in which Ph.D. students conducted team‐based research under the guidance of faculty mentors, and focused workshops which disseminated knowledge and shared experiences between scientists at many different career levels. The Summer Institutes were a test bed in which new ideas could be explored, assisted students in developing a wide range of skills, and were highly productive, but posed challenges for mentors and students because the ‘new’ research topics initiated during the Institutes' programmes needed to be completed in competition with students' ongoing Ph.D. research or mentor's existing research programs. The workshop‐based model circumvented this conflict and was also highly productive, but did not offer the same opportunity to experiment with new ideas as part of the synthesis research. Leadership, trust, flexibility and long gestation times were all important to bringing synthesis research to a positive resolution. Funding models that embrace the exploratory aspects of synthesis and provide adequate support to mentors and students over these long timescales would facilitate future hydrologic synthesis research. Copyright © 2011 John Wiley & Sons, Ltd.
Spectroscopic investigation of the interaction of the toxicant, 2‐naphthylamine, with bovine serum albumin
Authors: Liu Yan , Chen Mingmao , Bian Guangling , Liu Junfeng , Song Ling
Published: July 2011

The mechanism of interaction between bovine serum albumin (BSA) and 2‐naphthylamine (2‐NA) in aqueous solution was investigated by fluorescence spectroscopy, circular dichroism (CD) spectra, and UV–vis spectroscopy. It was proved from fluorescence spectra that the fluorescence quenching of BSA by 2‐NA was a result of the formation of complex between 2‐NA and BSA, and the binding constants (Ka) as well as the numbers of binding sites for 2‐NA in BSA were determined according to the modified Stern–Volmer equation. The results of synchronous fluorescence and CD spectra demonstrated 2‐NA could decrease the amount of α‐helix of BSA, leading to the loosening of protein skeleton. UV–vis spectroscopy and resonance light scattering spectra (RLS) results also suggested the conformation of BSA were changed and the BSA aggregation occured, which could induce toxic effects on the organism. © 2011 Wiley Periodicals, Inc. J Biochem Mol Toxicol 25:362–368 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/jbt.20400
Inactivation of Crotalus atrox venom hemorrhagic activity by direct current exposure using hens' egg assay
Authors: Calzia Daniela , Ravera Silvia , Aluigi Maria Grazia , Falugi Carla , Morelli Alessandro , Panfoli Isabella
Published: July 2011

The hemotoxic venoms of Viperidae and Crotalidae are responsible for most of the evenomations in the United States, West Africa, India, South‐East Asia, New Guinea, and Latin America. We previously reported that a short exposure of Crotalus atrox venom to direct electric current (dc) from a low‐voltage generator, in solution, causes consistent and irreversible inactivation of venom phospholipase A2 and metalloproteases. Here we report by in vivo assay on chicken embryos at stage 18 of development according to Hamburger and Hamilton that the hemorrhagic activity of C. atrox venom is lost after exposure to dc (from low voltage). Venom was exposed to dc ranging between 0 and 1 mA. dc values above 0.7 mA abolished hemorrhage. Such in vivo data, showing that dc neutralizes C. atrox venom hemorrhagic activity suggest that a deeper knowledge is needed to understand the relationship among dc and biological matter. © 2011 Wiley Periodicals, Inc. J Biochem Mol Toxicol 25:377–381 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/jbt.20404
Simultaneous removal of COD and NH3‐N in secondary effluent of high‐salinity industrial waste‐water by electrochemical oxidation
Authors: Huang Yao‐Kun , Li Shuang , Wang Can , Min Ji
Published: July 2011

BACKGROUND: Electrochemical oxidation has been applied successfully in industrial waste‐water treatment. The simultaneous removal of CODCr and NH3‐N, as well as the corresponding mechanisms and reaction zone, were examined in this study. The reaction kinetics and the significant factors that affect removal performance were also studied.

RESULTS: The CODCr removal efficiency without chlorides in waste‐water was only 11.8% after 120 min of treatment, which was much lower than the efficiency with chlorides, and agitation did not improve the performance. When the current density was increased from 2.5 to 10 mA cm−2, the removal efficiency was improved. The removal efficiencies of CODCr and NH3‐N were less at initial pH = 11 than at pH = 3 and 8.7 (without adjustment). The CODCr and NH3‐N removal efficiencies were decreased by about 30% and 50%, respectively, when the electrode distance was increased from 4 to 12 cm. Instantaneous current efficiency decreased with increase in current density.

CONCLUSIONS: The degradation of pollutants occurred mainly at the boundary layer between the electrode and the bulk solution. The indirect oxidation by active chlorine generated from the chlorides was proven to be the primary mechanism of electrochemical oxidation treatment. The removal of CODCr in this study followed a pseudo‐first‐order kinetic model. Copyright © 2011 Society of Chemical Industry
Trace detection of hormones and sulfonamides in viscous cosmetic products by neutral desorption extractive electrospray ionization tandem mass spectrometry
Authors: Liu Yan , Zhang Xinglei , Ouyang Yongzhong , Hu Zhong , Ma Li , Zhang Jinghua , Lin Jinming , Chen Huanwen
Published: July 2011

A sensitive method based on a geometry‐independent neutral desorption (GIND) in combination with extractive electrospray ionization mass spectrometry (EESI‐MS) has been developed for fast detection of illicit additives such as sulfonamides and hormones in highly viscous cosmetic products. The method gave a low limit of detection (LOD) (in the range of 0.001–1 ng/g), acceptable relative standard deviation (RSD = 6.8–11.4%) and reasonable recovery (87–116%) for direct measuring of nine types of hormones and sulfonamides in the cosmetic products. The average measurement time for two types of samples was less than 1 min. Trace amounts of analytes in commercial cosmetic products have been quantitatively detected, without any sample pretreatment. The experimental results showed that non‐volatile illicit additives such as sulfonamides and hormones could be sensitively liberated using the GIND device for quantitative detection from the highly viscous cosmetic products, demonstrating that GIND‐EESI‐MS is a promising tool for high throughput, sensitive and quantitative analysis of highly complex viscous samples. Copyright © 2011 John Wiley & Sons, Ltd.
Fibroblast growth factor‐2 deficiency causes defects in adult hippocampal neurogenesis, which are not rescued by exogenous fibroblast growth factor‐2
Authors: Werner Sandra , Unsicker Klaus , von Bohlen und Halbach Oliver
Published: July 2011

Neurogenesis within the adult brain is restricted to selected areas, one of which is the dentate gyrus (DG). Several growth factors have been reported to affect neurogenesis in the adult DG. However, a role of fibroblast growth factor‐2 (FGF‐2) in adult hippocampal neurogenesis has not been firmly established. We have analyzed neurogenesis in the DG using in vivo and in vitro approaches. FGF‐2–/– mice revealed no alterations in the number of proliferating cells but a significant decrease in the numbers of newly generated neurons. Moreover, FGF‐2 added to hippocampal slice cultures from FGF‐2–/– mice was unable to rescue the phenotype. Although an increase in death of neurogenic cells in the FGF‐2‐deficient DG could not be specifically demonstrated, there was a massive increase in global cell death in FGF‐2–/– hippocampal slice cultures compared with slices from wild‐type mice. Cell death could not be prevented by addition of FGF‐2. Neutralization of endogenous FGF‐2 in hippocampal slices did not interfere with neurogenesis in a short‐term paradigm. Together, our data suggest that FGF‐2 is essentially required for maturation of new neurons in adult hippocampal neurogenesis but is likely to operate synergistically in combination with other mechanisms/growth factors. © 2011 Wiley‐Liss, Inc.
Luteolin protects against reactive oxygen species‐mediated cell death induced by zinc toxicity via the PI3K–Akt–NF‐κB–ERK‐dependent pathway
Authors: Zhou Futao , Qu Lina , Lv Ke , Chen Hailong , Liu Jiankang , Liu Xinmin , Li Yinghui , Sun Xuechuan
Published: July 2011

Zinc ion elevation contributes to acute excitotoxic brain injury and correlates with the severity of dementia in chronic neurodegenerative diseases. Downstream control of zinc‐triggered signals is believed to be an efficient countermeasure. In the current study, we examined whether the flavonoid luteolin (Lu) could protect human neuroblastoma SH‐SY5Y cells against zinc toxicity. We found that Lu suppressed overproduction of reactive oxygen species and protected against apoptotic cell death induced by zinc. By using specific inhibitors, we found that zinc strongly triggered Akt and ERK1/2 activation via a PI3K–Akt–NF‐κB–ERK1/2‐dependent pathway. Furthermore, Lu completely blocked this activation. Our study strongly supports the hypothesis that Lu might protect SH‐SY5Y cells against ROS‐mediated apoptotic cell death induced by zinc in part by inhibiting the PI3K–Akt–NF‐κB–ERKs pathway. © 2011 Wiley‐Liss, Inc.
Assessment of zinc deficiency and effect of dietary carrot, amchur and onion on zinc status during repletion in zinc‐deficient rats
Authors: Gautam Smita , Platel Kalpana , Srinivasan Krishnapura
Published: July 2011

BACKGROUND: Food acidulants, β‐carotene‐rich vegetables and sulfur compound‐rich Allium spices are known to improve zinc bioaccessibility from food grains. This animal study evaluated the positive influence of these promoters of zinc bioaccessibility on zinc status during zinc repletion in Wistar rats previously rendered zinc‐deficient by feeding a zinc‐deficient semi‐synthetic diet for 4 weeks. Groups of these zinc‐deficient animals were subsequently maintained on a zinc‐containing grain‐based diet for 2 weeks. Various experimental diets consisted of the grain‐based diet supplemented with (1) carrot, (2) onion, (3) amchur, (4) carrot + amchur and (5) onion + amchur.

RESULTS: Zinc deficiency was confirmed by lower zinc concentration in tissues and bones and lower activity of zinc‐containing enzymes. Zinc concentration was 10–15% lower in serum, liver and kidney of zinc‐deficient rats. Bone weight in zinc‐deficient rats was 20% lower than that in normal rats. Activities of zinc‐containing enzymes (hepatic superoxide dismutase and alcohol dehydrogenase and serum alkaline phosphatase) were lower in the zinc‐deficient group. Animals fed diets supplemented with these promoters of zinc bioaccessibility showed better zinc status in tissues and bones compared with those repleted with the control stock diet.

CONCLUSION: This animal study supports the claim of promoters of zinc bioaccessibility for improving zinc status, which may find practical application. Copyright © 2011 Society of Chemical Industry
Relating raw rice colour and composition to cooked rice colour
Authors: Bett‐Garber Karen L , Champagne Elaine T , Thomson Jessica L , Lea Jeanne
Published: July 2011

BACKGROUND: The whiter the rice, the more it is preferred by consumers and the more value it has in the market place. The first objective of this study was to determine the interrelationships of raw colour, cooked colour, amylose content and protein content in rice. The second objective was to assess whether or not the colour of cooked rice can be predicted from raw rice colour in conjunction with amylose and protein contents.

RESULTS: Protein and amylose contents were not significantly correlated with the colour measurements for raw rice. Protein and amylose showed moderate, significant associations with L* and a* and a*, b* and C* respectively for cooked rice. Only the colour variable a* of cooked rice could be predicted using protein, amylose and raw rice colour with high enough precision to be useful, and this was only for modelling using samples cooked in the same manner (rice cooker). Cooking method (rice cooker versus excess water) affected the colour of cooked rice.

CONCLUSION: Being able to predict a* in cooked rice is likely of limited value. Only the model that used samples where postharvest handling conditions were controlled (US‐grown rice) was able to predict C*, a more useful measure, and then with only moderate ability. L*, a measure of brightness/whiteness, was not predicted well by any of the models. Copyright © 2011 Society of Chemical Industry
Strong cation exchange monoliths for HPLC by Reactive Gelation
Authors: Brand Bastian , Krättli Martin , Storti Giuseppe , Morbidelli Massimo
Published: July 2011

Polymeric monolithic stationary phases for HPLC can be produced by Reactive Gelation. Unlike the conventional method of using porogens, such novel process consists of a number of separate steps, thus enabling a better control of the quality of the final material. A suspension of polymer nanoparticles in water is produced and subsequently swollen with hydrophobic monomers. The particles are then destabilised (usually by salt addition) to make them aggregate into a large percolating structure, the so‐called monolith. Finally, the added monomer can then be polymerised to harden the structure. In this work, a polystyrene latex is used as the base material and functionalised by introduction of epoxide groups on the surface and subsequent reaction to sulphonic acid groups, yielding a ${\rm{SO}}_{\rm{3}}^{\rm{ - }}$ density of 0.7 mmol/g dry material. Morphological investigations show 54% porosity made of 300 nm large pores. Van Deemter measurements of a large protein show no practical influence of diffusion limitations on the plate number. Finally, a preliminary separation of a test protein mixture is shown, demonstrating the potential of using ion‐exchange chromatography on Reactive Gelation monoliths.
Real‐time motion and B0 correction for localized adiabatic selective refocusing (LASER) MRSI using echo planar imaging volumetric navigators
Authors: Hess Aaron T. , Andronesi Ovidiu C. , Dylan Tisdall M. , Gregory Sorensen A. , van der Kouwe André J. W. , Meintjes Ernesta M.
Published: July 2011

A method is presented to correct the effects of motion and motion‐related B0 perturbations on spectroscopic imaging in real time through the use of a volumetric navigator. It is demonstrated that, for an axial slice, lifting the chin significantly disrupts the B0 homogeneity in the zero‐order (frequency), first‐order Y (coronal) axis and second‐order ZY term. This volumetric navigator is able to measure and correct in real time both head pose and zero‐ to first‐order B0 inhomogeneities. The volumetric navigator was validated in six volunteers who deliberately lifted and then dropped their chin during the scan. These scans show that motion correction alone is not sufficient to recover the spectral quality. By applying real‐time shim adjustments, spectral quality was fully recovered to linewidths below 0.08 ppm and the signal‐to‐noise ratio to within acceptable limits in five of six subjects. In the sixth subject, 83% of the spectra within the volume of interest were recovered, compared with the worst case nonshim‐corrected scan, where none of the voxels fell within these quality bounds. It is shown that the use of a volumetric navigator comes at no additional cost to the scan time or spectral signal‐to‐noise ratio. Copyright © 2011 John Wiley & Sons, Ltd.
LMI‐based gain scheduling for bridge flutter control using eccentric rotational actuators
Authors: Körlin Rüdiger , Boonto Sudchai , Werner Herbert , Starossek Uwe
Published: July 2011

Long‐span bridge girders can show dangerous instable flutter vibrations caused by aerodynamic forces due to very strong winds. The control objective of flutter control is to enhance the structure‐dependent and control‐dependent critical wind speed of flutter onset. An active mass damper system with two eccentric rotational actuators (ERA) is presented for flutter control. By using a bridge girder model that moves in two degrees of freedom (DOFs) and is subjected to wind, the equations of motion of the controlled structure equipped with ERA are established. For determination of critical wind speed, a flutter analysis is carried out with the help of a numerical simulation scheme. Considering the plant without the aerodynamic forces and neglecting the interaction effects between the two ERA, the simplified control problem of one ERA is affine to the translational oscillator and rotational actuator (TORA) benchmark problem. LMI‐based gain scheduling technique has been used successfully for the TORA and is implemented for flutter control with ERA in this research. For an example, the performance of the controlled bridge girder is investigated. Copyright © 2011 John Wiley & Sons, Ltd.
Preparation and characterization of polyoxymethylene‐copolymer/hydroxyapatite nanocomposites for long‐term bone implants
Authors: Pielichowska Kinga , Szczygielska Agnieszka , Spasówka Ewa
Published: July 2011

In this work, new polyoxymethylene (POM)/hydroxyapatite (HAp) nanocomposites for long‐term bone implants have been obtained via extrusion and injection molding processes and characterized by differential scanning calorimetry (DSC), temperature‐modulated DSC (TMDSC), scanning electron microscopy (SEM), transmission electron microscopy (TEM), wide‐angle X‐ray diffraction (WAXD), Fourier transform infrared spectroscopy (FTIR), thermogravimetry (TG), and tensile mechanical and in vitro stability tests. Based on the DSC results, it was found that the degree of crystallinity increases for POM/0.5% HAp sample and decreases for POM/1.0% HAp and POM/2.5% HAp. SEM and TEM observations for POM/HAp nanocomposites indicated that the dispersion of HAp in the polymer matrix was uniform and the diameter of the HAp particles was less than 100 nm for most of them. Young's modulus increases with increasing HAp concentration, whereby elongation at break decreases. On the contrary, HAp concentration does not have a significant influence on the tensile strength. TG results show that for POM/0.5% HAp, POM/1.0% HAp, and POM/2.5% HAp, thermal stability slightly increases in comparison to pure POM, whereas for POM/5.0 HAp and POM/10.0% HAp, lower thermal stability was observed. In vitro data reveal that with an increase of HAp content, bioactivity of nanocomposites increases; a good in vitro chemical stability of POM and POM nanocomposites was confirmed. Copyright © 2011 John Wiley & Sons, Ltd.
Fetal cardiac evaluation at 11–14 weeks by experienced obstetricians in a low‐risk population
Authors: Volpe Paolo , Ubaldo Passamonti , Volpe Nicola , Campobasso Gianluca , Robertis Valentina De , Tempesta Annalisa , Volpe Grazia , Rembouskos Georgios
Published: July 2011

Objective

The aim of this study was to evaluate the detection rate of congenital heart diseases (CHD) in a low‐risk population by performing cardiac evaluation during the first‐trimester screening for chromosomal abnormalities. In this context, the role of four‐chamber view, tricuspid regurgitation and abnormal ductus venosus flow in the screening for cardiac anomalies in a low‐risk population was also investigated.

Method

The cardiac examination was performed by obstetricians with extensive experience in first‐ and second‐trimester ultrasound (US). Follow‐up US evaluations during the second and third trimesters were offered to all patients. In case of abnormal findings during routine assessment, fetal echocardiography was performed by a fetal cardiologist.

Results

Among the 4445 fetuses included in the study, 42 CHD were detected (39 diagnosed prenatally and 3 postnatally). In 27 cases, the fetal cardiologist confirmed the type of CHD diagnosed at US screening. In 1 case, the diagnosis was slightly different in the second trimester, and in 3 of the 26 correctly diagnosed in the first‐trimester cases, the CHD developed and progressed in severity. A significant association of major CHD and US first‐trimester markers was observed.

Conclusions

First‐trimester assessment of the fetal heart is feasible in a low‐risk population when performed by experienced obstetricians. However, although most types of CHD can be diagnosed early in pregnancy, some may become apparent later in gestation. Copyright © 2011 John Wiley & Sons, Ltd.
Synthesis and characteristics of thermoplastic elastomer based on polyamide‐6
Authors: Yi Chunwang , Peng Zhihan , Wang Huaping , Li Min , Wang Chaosheng
Published: July 2011

A new class of polyether amide thermoplastic elastomers (TPAE) was synthesized via a three‐step polymerization route. In the first step a binary carboxyl terminated polyamide‐6 (PA6) with relatively low number‐average molecular weight was prepared via a caprolactam hydrolytic ring‐opening process. 4,4′‐Diphenylmethane diisocyanate (MDI) was reacted with the PA6 to produce PA6–MDI hard segments in the second step. Chain extension of the hard segments with poly(tetramethylene glycol) was the last step to furnish a series of new TPAEs. Structural characterization, physical properties and the effects of reaction conditions on the properties of the copolymer were investigated by infrared spectroscopy, 1H nuclear magnetic resonance spectroscopy and other analytical techniques. Possible side reactions and phase separation are reported. Copyright © 2011 Society of Chemical Industry
4‐Quinolylnitrene and 2‐quinoxalinylcarbene
Authors: Addicott Chris , Lüerssen Holger , Kuzaj Martin , Kvaskoff David , Wentrup Curt
Published: July 2011

Matrix photolysis of 4‐quinolyl azide 22 affords 4‐quinolylnitrene 21, identified by electron spin resonance (ESR) and infrared (IR) spectroscopy. Minor absorptions assigned to azirene 23 (1741 cm−1) were also observed. Further photolysis affords strong absorptions at 1902 and 1909 cm−1 ascribed to the cyclic ketenimine 19 as well as weaker absorptions at 2044 cm−1 ascribed to the open‐chain ketenimine 26 and at 1982 cm−1 assigned to the open‐chain nitrile ylide 25. Both 2‐(5‐tetrazolyl)quinoxaline 14 and triazolo[1,5‐a]quinoxaline 16 give rise to an absorption at 2084 cm−1 because of formation of the diazo compound 15 on mild flash vacuum thermolysis (FVT) with Ar matrix isolation of the product. Matrix photolysis of 16 affords diazo compound 15, cyclic ketenimine 19 and open‐chain ketenimine 26. 2‐Quinoxalinylcarbene 17 was also formed in the matrix photolysis and identified by its ESR spectrum. FVT of either 22 or 15/16 afforded 4‐quinolylnitrene, identified by its Ar‐matrix ESR spectrum. A second nitrene ESR signal obtained in several FVT and photolysis experiments from both 22 and 16 is ascribed to the phenylnitrene derivative 24 formed by ring opening of 2‐quinoxalinylcarbene 17. FVT of 14, 16, and 22 affords 3‐cyanoindole 27 as the major product. Minor amounts of 2‐cyanoindole 28, 4‐aminoquinoline 29 and 4,4′‐azoquinoline 30 are also formed. Preparative photolysis of 22 in solution in the presence of dialkylamines leads to trapping of the azirene 23 to afford 5‐dialkylaminobenzo[e]‐1,4‐diazepines 35. Copyright © 2011 John Wiley & Sons, Ltd.
Silole‐containing polymers for high‐efficiency polymer solar cells
Authors: Song Jinsheng , Du Chun , Li Cuihong , Bo Zhishan
Published: July 2011

Silole‐containing conjugated polymers (P1 and P2) carrying methyl and octyl substituents, respectively, on the silicon atom were synthesized by Suzuki polycondensation. They show strong absorption in the region of 300–700 nm with a band gap of about 1.9 eV. The two silole‐containing conjugated polymers were used to fabricate polymer solar cells by blending with PC61BM and PC71BM as the active layer. The best performance of photovoltaic devices based on P1/PC71BM active layer exhibited power conversion efficiency (PCE) of 2.72%, whereas that of the photovoltaic cells fabricated with P2/PC71BM exhibited PCE of 5.08%. 1,8‐Diiodooctane was used as an additive to adjust the morphology of the active layer during the device optimization. PCE of devices based on P2/PC71BM was further improved to 6.05% when a TiOx layer was used as a hole‐blocking layer. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011
Parameters influencing the molecular weight of 3,6‐carbazole‐based D‐π‐A‐type copolymers
Authors: Fu Yuanhe , Kim Jinseck , Siva Ayyanar , Shin Won Suk , Moon Sang‐jin , Park Taiho
Published: July 2011

Condensation copolymerization reactions of carbazole 3,6‐diboronate with 4,7‐bis(5‐bromo‐2‐thienyl)‐2,1,3‐benzothiadiazole (DTBT) only produce low‐molecular‐weight donor (D)‐π‐acceptor (A) copolymers. High‐molecular‐weight copolymers for use in optoelectronic devices are necessary for achieving extended π‐conjugation and for controlling the copolymer processibility. To elucidate the cause of the persistently low molecular weight, we synthesized three 3,6‐carbazole‐based D‐A copolymers using copolymerizations of N‐9′‐heptadecanyl‐3,6‐carbazole with DTBT, N‐9′{2‐[2‐(2‐methoxy‐ethoxy)‐ethoxy]‐ethyl}‐3,‐6‐carbazole with DTBT, and N‐9′‐heptadecanyl‐3,6‐carbazole with alkyl‐substituted DTBT. We investigated several parameters for their influence on molecular copolymer weight, including the conformation of the chain during growth, the solubility of the monomers, and the dihedral angles between the donor and acceptor units. Size exclusion chromatography, UV–vis absorption spectroscopy, and computational studies revealed that the low molecular weights of 3,6‐carbazole‐based D‐A copolymers resulted from conjugation breaks and the resulting high coplanarity, which led to strong interactions between polymer chains. These interactions limited formation of high‐molecular‐weight‐copolymers during copolymerization. The strong intermolecular interactions of the 3,6‐carbazole moiety were exploited by incorporating 3,6‐carbazole units into poly[9′,9′‐dioctyl‐2,7‐flourene‐alt‐5,5‐(4′,7′‐di‐2‐thienyl‐2′,1′,3′‐benzothiadiazole)] prepared from 9′,9′‐dioctyl‐2,7‐flourene and DTBT. Interestingly, the number average molecular weight increased gradually with increasing 2,7‐fluorene monomer content but the number of conjugation breaks was a range of 6–7. The hole mobilities of the copolymers were studied for comparison purposes. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011
Bandgap engineering of indenofluorene‐based conjugated copolymers with pendant donor‐π‐acceptor chromophores for photovoltaic applications
Authors: Duan Chunhui , Cai Wanzhu , Zhong Chengmei , Li Yanhu , Wang Xiaohui , Huang Fei , Cao Yong
Published: July 2011

Three narrow‐band‐gap conjugated copolymers based on indenofluorene and triphenylamine with pendant donor‐π‐acceptor chromophores were successfully synthesized by post‐functionalization approach. All the polymers have good solubility in common solvents and excellent thermal stability. The photophysical properties, energy levels and band gaps of the polymers were well manipulated by introducing different acceptor groups onto the end of their conjugated side chains. By using different acceptor groups, the band gaps of the polymers were narrowed from 1.86 to 1.53 eV by lowering their lowest unoccupied molecular orbital levels, whereas their relatively deep highest occupied molecular orbital levels of approximately −5.35 eV were maintained. Bulk‐heterojunction solar cells with these polymers as electron donors and (6,6)‐phenyl‐C71‐butyric acid methyl ester as acceptor showed power conversion efficiencies as high as 3.1% and high open circuit voltages more than 0.88 eV. The relationships between the performance and film morphology, energy levels, charge mobilities were discussed. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011