bluuebunny/crossref_metadata_2025 huggingface dataset:
A serological and molecular survey of hepatitis B in children 15 years after inception of the national hepatitis B vaccination program in eastern China
Authors: Dong Ying , Liu She‐Lan , Zhai Xiang‐Jun , Zhu Feng‐Cai , Pan Hao , Yu Jia‐xi , Chen Yin‐zhong , Xie Yi‐Rui , Zhang Xiao‐Yu , Zhang Hong‐Mei , Li Lan‐Juan , Wang Hua , Ruan Bing
Published: July 2009

The emergence of mutations in the hepatitis B virus (HBV) S gene has threatened the long‐term success of vaccination programs since the worldwide introduction of effective vaccines against hepatitis B. This study was conducted on 5,407 children (0–8 years old) in eastern China in 2007. We analyzed the prevalence of HBsAg, anti‐HBs, and “a”‐determinant mutations in the HBV S gene by microparticle enzyme immunoassays, PCR, and DNASTAR software. The total HBsAg prevalence was 1.52% (82/5,407) in the children and increased with age. In contrast, the positive rate (65.42%, 2,374/3,629) and the titers of anti‐HBs decreased with age. The predominant infection was HBV of genotype C and serotype adr (45/51; 88% of cases). Mutations of I126T, amino acid 137 (nt553T deletion mutation), G145A, G145R, and F158S were found in the children; the mutations of amino acid 137 and F158S have not been reported previously. The total prevalence of mutant strains was 14% (7/51). To investigate whether the infection resulted from maternal transmission, we compared the S gene sequences in 16 mother–child pairs. Fourteen mother–child pairs exhibited the same HBV genotype, with 99.5–100% sequence homology in the S gene, while two pairs exhibited different genotypes. This study suggested that the hepatitis B vaccination strategies in eastern China have been successful. Although the emergence of “a”‐determinant mutations in the HBV S gene have resulted in HBV infection in immunized children, this does not pose a threat to the vaccination strategies. The HBV‐infected children had contracted the infection via vertical transmission. J. Med. Virol. 81:1517–1524, 2009. © 2009 Wiley‐Liss, Inc.
Three cases of paralytic poliomyelitis associated with type 3 vaccine poliovirus strains in Bulgaria
Authors: Korsun Neli , Kojouharova Mira , Vladimirova Nadezhda , Fiore Lucia , Litvinenko Ivan , Buttinelli Gabriele , Fiore Stefano , Voynova‐Georgieva Violeta , Mladenova Zornitsa , Georgieva Daniela
Published: July 2009

Oral poliovirus vaccine (OPV) can cause, in extremely rare cases vaccine‐associated paralytic poliomyelitis in recipients, or contacts of vaccinees. Three cases of vaccine‐associated paralytic poliomyelitis (two contacts and one recipient) occurred in the Bourgas region of Bulgaria in the spring of 2006. The first two cases, notified as acute flaccid paralysis, were 55 days old unvaccinated twin brothers, having been in contact with vaccinees. The third case concerned a 4‐month‐old infant who had received the first OPV dose 37 days prior to the onset of illness. Complete clinical, epidemiological, virological, serological and molecular investigations of the children with paralysis and their contacts were undertaken. In all the three cases type 3 polioviruses were isolated from fecal samples and characterized as Sabin‐like poliovirus strains. Type 3 polioviruses isolated from the twin brothers demonstrated by sequence analysis U‐to‐C back mutation at nt 472 of the 5′ UTR, known to correlate with neurovirulence, and mutation in the VP1 region. Type 3 poliovirus isolated from the third child demonstrated in the 3D sequenced region a recombination with Sabin type 1 poliovirus. In the latter region, three silent mutations and one, resulting in amino acid substitution, were also observed. The clinical, epidemiological and virological data and the neurological sequelae observed 60 days following the onset of paralysis, confirmed the diagnosis of vaccine‐associated paralytic poliomyelitis in all the three patients. J. Med. Virol. 81:1661–1667, 2009. © 2009 Wiley‐Liss, Inc.
Surveillance and oseltamivir resistance of human influenza a virus in Turkey during the 2007–2008 season
Authors: Ciblak Meral Akcay , Hasoksuz Mustafa , Escuret Vanessa , Valette Martine , Gul Fadime , Yilmaz Huseyin , Turan Nuri , Bozkaya Emel , Badur Selim
Published: July 2009

Monitoring the activity of influenza viruses is important for establishing the circulating types and for detection of the emergence of novel sub‐types and antiviral resistant strains. This is the first report from Turkey on the surveillance and oseltamivir resistance of influenza viruses in 2007–2008. Five hundred twenty‐four nasal swabs were tested from different geographical regions in Turkey during November 2007–April 2008. One hundred sixty‐three (31%) samples were positive for influenza viruses of which 111 (68%) were influenza A, 52 (31%) influenza B using an immuno‐capture ELISA. Forty isolates were selected at random from influenza A positive samples and grown in MDCK cell cultures. The supernatant of the cell cultures was used for RNA extraction followed by RT‐PCR to detect the sub‐types. Sub‐typing revealed all samples as A/H1N1. The N1 gene segment of 30 A/H1N1 samples was sequenced in part, from the 201st to 365th residue, which included the critical region for oseltamivir resistance. Then resulting sequences were analyzed with oseltamivir sensitive and resistant strains obtained from National Center for Biotechnology Information (NCBI) GenBank by CLC Main Workbench Software. H275Y (H274Y according to N2 numbering) mutation, which is known to confer resistance to oseltamivir, was detected in 6 out of 30 (20%) H1N1 isolates from four cities (Istanbul, Bursa, Ankara, and Izmir). The D354G mutation was observed in all oseltamivir resistant H1N1 isolates but not in the oseltamivir sensitive isolates. Assay of neuraminidase activity revealed that these isolates were resistant to oseltamivir, but sensitive to zanamivir. J. Med. Virol. 81:1645–1651, 2009. © 2009 Wiley‐Liss, Inc.
Prevalence of the K65R resistance reverse transcriptase mutation in different HIV‐1 subtypes in Israel
Authors: Turner Dan , Shahar Eduardo , Katchman Eugene , Kedem Eynat , Matus Natasha , Katzir Michal , Hassoun Gamal , Pollack Shimon , Kessner Rivka , Wainberg Mark A. , Avidor Boaz
Published: July 2009

The K65R mutation in HIV‐1 reverse transcriptase (RT) can be selected by the RT inhibitors tenofovir (TDF), abacavir (ABC), and didanosine (DDI). Recently, in vitro studies have shown that K65R is selected in tissue culture more rapidly with subtype C than subtype B viruses. The prevalence of K65R in viruses sequenced at the Tel‐Aviv AIDS Center was evaluated. This study analyzed retrospectively sequences from 1999 to 2007 in patients treated with TDF, ABC, and/or DDI and compared rates of mutational prevalence between subtypes. Fisher's exact test was used to determine statistical significance. Forty‐four sequences from patients treated with the three above‐cited drugs were analyzed. Subtypes A (n = 1), CRF01_AE (n = 4), CRF02_AG (n = 2), B (n = 21), C (n = 11), D (n = 1), F (n = 3), and G (n = 1) were represented. Seven non‐B viruses had the K65R mutation, which was only found in one subtype B virus. Of these seven samples four were subtype C, one was subtype CRF01_AE, and two were subtype CRF02_AG. None of the eight viruses with K65R harbored thymidine analogue mutations. In this study, non‐subtype B viruses possessed the K65R mutation at higher incidence than subtype B viruses. Subtype C viruses may be especially prone to develop this mutation. Larger studies are needed to confirm these data. Efforts should be intensified to understand better differences in drug resistance between various HIV subtypes. J. Med. Virol. 81:1509–1512, 2009. © 2009 Wiley‐Liss, Inc.
Serologic and genotypic analysis of a series of herpes simplex virus type 1 isolates from two patients with genital herpes
Authors: Umene Kenichi , Kawana Takashi , Fukumaki Yasuyuki
Published: July 2009

Herpes simplex virus type 1 (HSV‐1) has been reported increasingly as a cause of genital herpes, although HSV‐1 is usually associated with oro‐labial herpes. In the present study, serum specimens and materials for viral isolation were obtained serially from two patients with recrudescent HSV‐1 genital infections to study serology and molecular epidemiology. Recurrent episodes, during which HSV‐1 was isolated, were followed by an increase in the level of anti‐HSV‐1 antibody, suggesting a booster effect from re‐exposure to viral antigens and the possible usefulness of the variation in the level of anti‐HSV‐1 antibody to diagnose recurrence. While genotypes of HSV‐1 isolates obtained from one patient were different from those from the other patient, genotypes of sequential HSV‐1 isolates obtained from the same patient were the same, implying that the recrudescent genital lesions of the two patients could be attributed to endogenous recurrence of a latent virus. Sera from one patient neutralized HSV‐1 isolates obtained from the other patient as well as HSV‐1 isolates obtained from the same patient. An HSV‐1 isolate obtained during a later episode in one patient was neutralized by sera taken before/during the later episode of the same patient, as effectively as an HSV‐1 isolate obtained during an earlier episode in the same patient; thus, in these two cases, HSV‐1 was assumed to have multiplied during recurrence despite the presence of an anti‐HSV‐1 antibody that could neutralize experimentally HSV‐1. J. Med. Virol. 81:1605–1612, 2009. © 2009 Wiley‐Liss, Inc.
Molecular and epidemiological features of GIIb norovirus outbreaks in Victoria, Australia, 2002–2005
Authors: Bruggink L.D. , Marshall J.A.
Published: July 2009

The epidemiology of GIIb norovirus outbreaks and the characteristics of GIIb open reading frame (ORF) 2 recombinant forms are poorly understood and this study examined these questions using norovirus‐associated gastroenteritis outbreaks in Victoria, Australia, during 2002–2005. Twenty‐one GIIb outbreaks were detected and were the second most common ORF 1 norovirus outbreak genotype (5%) after GII.4 (90%). Both GIIb and GII.4 outbreaks peaked in warmer months of the year but their periodicity was different. ORF 2 sequencing analysis was carried out in the two regions previously designated C and D. RT‐PCR region D primers were less sensitive than region C primers. No evidence of recombination between regions C and D was found. ORF 2 genotypes for the 21 GIIb outbreaks were: GII.1 (10 outbreaks), GII.3 (10 outbreaks) and, apparently for the first time, GII.13 (1 outbreak). GIIb outbreaks could occur in a broad range of settings and there was no correlation between ORF 2 genotype and setting except that all 5 outbreaks involving mainly young children were associated with GIIb/GII.3. J. Med. Virol. 81:1652–1660, 2009. © 2009 Wiley‐Liss, Inc.
Investigations of the usefulness of average models for calculations characteristics of buck and boost converters at the steady state
Authors: Górecki Krzysztof , Zarębski Janusz
Published: July 2009

This paper deals with the problem of the analysis of boost and buck converters at the steady state with the use of the method of average models. The usefulness of this method is examined by comparing the boost and buck converters characteristics at the steady‐state obtained both with the transient analysis with physical models of semiconductor devices and the examined method as well. The accuracy of the method of the average models is investigated with respect to the values of the circuit load resistance, the pulse‐duty factor and the frequency of the signal controlling the power switch. Copyright © 2009 John Wiley & Sons, Ltd.
Atmospheric pressure ion sources
Authors: Covey Thomas R. , Thomson Bruce A. , Schneider Bradley B.
Published: July 2009

This review of atmospheric pressure ion sources discusses major developments that have occurred since 1991. Advances in the instrumentation and understanding of the key physical principles are the primary focus. Developments with electrospray and atmospheric pressure chemical ionization and variations encompassing adaptations for surface analysis, ambient air analysis, high throughput, and modification of the ionization mechanism are covered. An important and limiting consequence of atmospheric pressure chemical ionization, chemical noise, is discussed as is techniques being employed to ameliorate the problem. Ion transfer and transport from atmospheric pressure into deep vacuum is an area undergoing constant improvement and refinement so is given considerable consideration in this review. © 2009 Wiley Periodicals, Inc., Mass Spec Rev 28:870–897, 2009
Involvement of p53 in oroxylin A‐induced apoptosis in cancer cells
Authors: Mu Rong , Qi Qi , Gu Hongyan , Wang Jia , Yang Yong , Rong Jingjing , Liu Wei , Lu Na , You Qidong , Guo Qinglong
Published: July 2009

Oroxylin A, a naturally occurring monoflavonoid extracted from Scutellariae radix, exhibits anticancer activity and induces apoptosis in human hepatocellular carcinoma HepG2 cells according to our previous data. In this study, we investigate whether p53 is involved in oroxylin A‐triggered viability inhibition and apoptosis induction in cancer cells. In a panel of different cancer cell lines, more potent inhibitory effects of oroxylin A were observed in wtp53 cells than those in mtp53 or p53‐null cells. Moreover, p53‐siRNA‐transfected HepG2 cells showed lower levels of apoptosis induced by oroxylin A than control‐siRNA‐transfected cells. Likewise, after oroxylin A treatment, p53‐null K‐562 cells displayed promoted apoptosis rate when transfected with wtp53 plasmid. Western blot and real‐time RT‐PCR assay revealed that oroxylin A markedly upregulated p53 protein expression in HepG2 and p53‐overexpressing K‐562 cells, but had no influence on p53 mRNA synthesis. Furthermore, after co‐treatment with cycloheximide, oroxylin A still exerted a little effect on p53 expression. The negative regulator of p53, MDM2 protein was detected, and downregulated expression was observed. In the presence of MG132, an inhibitor of proteasome‐mediated proteolysis, no change in p53 expression was obtained. Additionally, the antioxidant N‐acetyl‐L‐cysteine could obviously abrogate p53 stabilization triggered by oroxylin A. Therefore, it is summarized that oroxylin A stabilized p53 expression and induced apoptosis at the posttranslational level via downregulating MDM2 expression and interfering MDM2‐modulated proteasome‐related p53 degradation. This indicated that oroxylin A could be served as a potential, novel agent candidate for cancer therapy. © 2009 Wiley‐Liss, Inc.
Yet another ten stories on antiviral drug discovery (part D): Paradigms, paradoxes, and paraductions
Authors: De Clercq Erik
Published: July 2009

This review article presents the fourth part (part D) in the series of stories on antiviral drug discovery. The stories told in part D focus on: (i) the cyclotriazadisulfonamide compounds; (ii) the {5‐[(4‐bromophenylmethyl]‐2‐phenyl‐5H‐imidazo[4,5‐c]pyridine} compounds; (iii) (1H,3H‐thiazolo[3,4‐a]benzimidazole) derivatives; (iv) T‐705 (6‐fluoro‐3‐hydroxy‐2‐pyrazinecarboxamide) and (v) its structurally closely related analogue pyrazine 2‐carboxamide (pyrazinamide); (vi) new strategies for the treatment of hemorrhagic fever virus infections, including, as the most imminent, (vii) dengue fever, (viii) the veterinary use of acyclic nucleoside phosphonates; (ix) the potential (off‐label) use of cidofovir in the treatment of papillomatosis, particularly RRP (recurrent respiratory papillomatosis); and (x) finally, the prophylactic use of tenofovir to prevent HIV infections. © 2009 Wiley Periodicals, Inc. Med Res Rev, 30, No. 4, 667–707, 2010
Identification of ataxia‐associated mtDNA mutations (m.4052T>C and m.9035T>C) and evaluation of their pathogenicity in transmitochondrial cybrids
Authors: Sikorska Marianna , Sandhu Jagdeep K. , Simon David K. , Pathiraja Vimukthi , Sodja Caroline , Li Yan , Ribecco‐Lutkiewicz Maria , Lanthier Patricia , Borowy‐Borowski Henryk , Upton Adrian , Raha Sandeep , Pulst Stefan M. , Tarnopolsky Mark A.
Published: July 2009

The potential pathogenicity of two homoplasmic mtDNA point mutations, 9035T>C and 4452T>C, found in a family afflicted with maternally transmitted cognitive developmental delay, learning disability, and progressive ataxia was evaluated using transmitochondrial cybrids. We confirmed that the 4452T>C transition in tRNAMet represented a polymorphism; however, 9035T>C conversion in the ATP6 gene was responsible for a defective F0‐ATPase. Accordingly, mutant cybrids had a reduced oligomycin‐sensitive ATP hydrolyzing activity. They had less than half of the steady‐state content of ATP and nearly an 8‐fold higher basal level of reactive oxygen species (ROS). Mutant cybrids were unable to cope with additional insults, i.e., glucose deprivation or tertiary‐butyl hydroperoxide, and they succumbed to either apoptotic or necrotic cell death. Both of these outcomes were prevented by the antioxidants CoQ10 and vitamin E, suggesting that the abnormally high levels of ROS were the triggers of cell death. In conclusion, the principal metabolic defects, i.e., energy deficiency and ROS burden, resulted from the 9035T>C mutation and could be responsible for the development of clinical symptoms in this family. Furthermore, antioxidant therapy might prove helpful in the management of this disease. Muscle Nerve, 2009
Aspects of the use of orthogonal basis functions in the element‐free Galerkin method
Authors: Zhuang Xiaoying , Augarde Charles
Published: July 2009

The element‐free Galerkin (EFG) method is probably the most widely used meshless method at present. In the EFG method, shape functions are derived from a moving least‐squares approximation using a polynomial basis, a calculation involving the inversion of a small matrix. A new implementation of the EFG method was published soon after the original where an alternative approach using an orthogonal basis was proposed to avoid matrix inversion in the formulation of the shape functions. In this paper we revisit this topic and show that the difficulties associated with the use of a polynomial basis remain present in the orthogonal case. We also show that certain terms in the derivative expressions are omitted in the new implementation of the EFG, which can lead to errors. Finally, we propose a new approach that avoids inversion while maintaining accuracy. Copyright © 2009 John Wiley & Sons, Ltd.
The proform of eosinophil major basic protein: a new maternal serum marker for adverse pregnancy outcome
Authors: Pihl Kasper , Larsen Torben , Rasmussen Steen , Krebs Lone , Christiansen Michael
Published: July 2009

Objective

To establish the first trimester serum levels of the proform of eosinophil major basic protein (proMBP) in pregnancies with adverse outcome. Furthermore, to determine the screening performance using proMBP alone and in combination with other first trimester markers.

Methods

A case‐control study was conducted in a primary hospital setting. The proMBP concentration was measured in cases with small‐for‐gestational age (SGA) (n = 150), spontaneous preterm delivery (n = 88), preeclampsia (n = 40), gestational hypertension (n = 10) and in controls (n = 500). Concentrations were converted to multiples of the median (MoM) in controls and groups were compared using Mann–Whitney U‐test. Logistic regression analysis was used to determine significant factors for predicting adverse pregnancy outcome. Screening performance was assessed using receiver operating characteristic curves.

Results

The proMBP median was significantly reduced in pregnancies with SGA (0.81 MoM), spontaneous preterm delivery (0.83 MoM), preeclampsia (0.88 MoM) and gestational hypertension (0.60 MoM). The best screening performance was found for preeclampsia including the covariates proMBP and nulliparity yielding an area under the curve equal to 0.737 (p < 0.0005) and a 75% detection rate for a 30% false positive rate.

Conclusion

The proMBP is a novel first trimester serum marker for adverse pregnancy outcome. Copyright © 2009 John Wiley & Sons, Ltd.
Surface modification of multiwalled carbon nanotubes with biocompatible polymers via ring opening and living anionic surface initiated polymerization. Kinetics and crystallization behavior
Authors: Priftis Dimitrios , Sakellariou Georgios , Hadjichristidis Nikos , Penott Evis K. , Lorenzo Arnaldo T. , Müller Alejandro J.
Published: July 2009

Multiwalled carbon nanotubes (MWNTs) were functionalized with 2‐hydroxyethyl benzocyclobutene (BCB‐EO) through a Diels–Alder cycloaddition reaction. The functionalized MWNTs were utilized for the surface initiated ring opening (ROP) catalyzed and anionic polymerization of ε‐caprolactone (ε‐CL) and ethylene oxide (EO), respectively. The kinetics of the ROP of ε‐CL was monitored through thermogravimetric analysis (TGA) which revealed that the polymerization proceeds very fast as compared to that of EO and that both polymerizations could be controlled with time. 1H NMR, Raman and FTIR spectroscopy, TGA, DSC, and transmission electron microscopy (TEM) were employed for the characterization of these polymer/CNT hybrids. DSC results showed that a remarkable nucleation effect is produced by MWNTs that reduced the supercooling needed for crystallization of both PεCL and PEO. Furthermore, the isothermal crystallization kinetics of the grafted PεCL and PEO was substantially accelerated compared to the neat polymers. The strong impact on the nucleation and crystallization kinetics is attributed to the covalent MWNT‐polymer bonding. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 4379–4390, 2009
Synthesis and characterization of nylon 18 18 and nylon 18 adamantane
Authors: Bennett Carl , Kaya Ethem , Sikes Allison M. , Jarrett William L. , Mathias Lon J.
Published: July 2009

Nylon 18 18 and nylon 18 1,3‐adamantanedicarboxylic acid (ADA) have been synthesized via melt polycondensation and characterized by thermal and spectroscopic techniques. Good film forming behavior combined with film toughness and flexibility indicate reasonable molecular weights for both. The higher aliphatic content of nylon 18 18 leads to increased resistance to common organic solvents over commercial nylons. Crystallization of nylon 18 18 combines hydrogen bonding of the amide units with a more significant contribution from van der Waals forces than possible for lower aliphatic content nylons due to the greater aliphatic chain lengths. Solid state 15N CP/MAS NMR indicates a mostly amorphous polymer, with crystalline regions comprised of the thermodynamically stable α‐form generally adopted by even–even nylons. Nylon 18 ADA as‐produced is completely amorphous as determined by differential scanning calorimetry. However, solution cast samples of nylon 18 ADA shows some ordered structures that can grow into more stable crystals with annealing. These crystals, once melted, do not recrystallize possibly due to chain rearrangement inhibited by bulky adamantly‐groups. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 4409–4419, 2009
AB2‐type amphiphilic block copolymers composed of poly(ethylene glycol) and poly(N‐isopropylacrylamide) via single‐electron transfer living radical polymerization: Synthesis and characterization
Authors: Tang Xinde , Liang Xiaochao , Yang Qian , Fan Xinghe , Shen Zhihao , Zhou Qifeng
Published: July 2009

Novel AB2‐type amphiphilic block copolymers of poly(ethylene glycol) and poly(N‐isopropylacrylamide), PEG‐b‐(PNIPAM)2, were successfully synthesized through single‐electron transfer living radical polymerization (SET‐LRP). A difunctional macroinitiator was prepared by esterification of 2,2‐dichloroacetyl chloride with poly(ethylene glycol) monomethyl ether (PEG). The copolymers were obtained via the SET‐LRP of N‐isopropylacrylamide (NIPAM) with CuCl/tris(2‐(dimethylamino)ethyl)amine (Me6TREN) as catalytic system and DMF/H2O (v/v = 3:1) mixture as solvent. The resulting copolymers were characterized by gel permeation chromatography and 1H NMR. These block copolymers show controllable molecular weights and narrow molecular weight distributions (PDI < 1.15). Their phase transition temperatures and the corresponding enthalpy changes in aqueous solution were measured by differential scanning calorimetry. As a result, the phase transition temperature of PEG44‐b‐(PNIPAM55)2 is similar to that in the case of PEG44‐b‐PNIPAM110; however, the corresponding enthalpy change is much lower, indicating the significant influence of the macromolecular architecture on the phase transition. This is the first study into the effect of macromolecular architecture on the phase transition using AB2‐type amphiphilic block copolymer composed of PEG and PNIPAM. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 4420–4427, 2009
Preparation and characterization of cellulose and konjac glucomannan blend film from ionic liquid
Authors: Yu Zhaoju , Jiang Yuanqin , Zou Weiwei , Duan Jiangjiang , Xiong Xiaopeng
Published: July 2009

Blend films from cellulose and konjac glucomannan (KGM) in room temperature ionic liquid 1‐allyl‐3‐methylimidazolium chloride were satisfactorily prepared by coagulating with water. The composition of the blend films was gravimetrically analyzed, and the compatibility of the two natural polymers was characterized by Fourier transform infrared spectroscopy and wide‐angle X‐ray diffraction. The results indicate good compatibility and strong interactions between cellulose and KGM, resulting in almost no loss of the water‐soluble KGM from the blend films even after the water coagulating and washing. However, microstructure analyses portrayed phase separations in the blend films, namely, egg‐like new phase particles were embedded in a continuous matrix base (MB). Phase diagram analysis and differential scanning calorimetry of the phase inversion coagulation process suggest that relative low molecular mass part of both cellulose and KGM formed the continuous MB, whereas the egg‐like new phase particles were super patterns of relative high molecular mass of both polymers, which played an important role in strengthening the blend material. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 1686–1694, 2009
Molecular mobility of poly(methyl methacrylate) glass during uniaxial tensile creep deformation
Authors: Lee Hau‐Nan , Paeng Keewook , Swallen Stephen F. , Ediger M. D. , Stamm Rebecca A. , Medvedev Grigori A. , Caruthers James M.
Published: July 2009

An optical photobleaching method has been used to measure the segmental dynamics of a poly(methyl methacrylate) (PMMA) glass during uniaxial creep deformation at temperatures between Tg − 9 K and Tg − 20 K. Up to 1000‐fold increases in mobility are observed during deformation, supporting the view that enhanced segmental mobility allows flow in polymer glasses. Although the Eyring model describes this mobility enhancement well at low stress, it fails to capture the dramatic mobility enhancement after flow onset, where in addition the shape of the relaxation time distribution narrows significantly. Regions of lower mobility accelerate their dynamics more in response to an external stress than do regions of high mobility. Thus, local environments in the sample become more dynamically homogeneous during flow. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 1713–1727, 2009
Identification, analysis, and prediction of protein ubiquitination sites
Authors: Radivojac Predrag , Vacic Vladimir , Haynes Chad , Cocklin Ross R. , Mohan Amrita , Heyen Joshua W. , Goebl Mark G. , Iakoucheva Lilia M.
Published: July 2009

Ubiquitination plays an important role in many cellular processes and is implicated in many diseases. Experimental identification of ubiquitination sites is challenging due to rapid turnover of ubiquitinated proteins and the large size of the ubiquitin modifier. We identified 141 new ubiquitination sites using a combination of liquid chromatography, mass spectrometry, and mutant yeast strains. Investigation of the sequence biases and structural preferences around known ubiquitination sites indicated that their properties were similar to those of intrinsically disordered protein regions. Using a combined set of new and previously known ubiquitination sites, we developed a random forest predictor of ubiquitination sites, UbPred. The class‐balanced accuracy of UbPred reached 72%, with the area under the ROC curve at 80%. The application of UbPred showed that high confidence Rsp5 ubiquitin ligase substrates and proteins with very short half‐lives were significantly enriched in the number of predicted ubiquitination sites. Proteome‐wide prediction of ubiquitination sites in Saccharomyces cerevisiae indicated that highly ubiquitinated substrates were prevalent among transcription/enzyme regulators and proteins involved in cell cycle control. In the human proteome, cytoskeletal, cell cycle, regulatory, and cancer‐associated proteins display higher extent of ubiquitination than proteins from other functional categories. We show that gain and loss of predicted ubiquitination sites may likely represent a molecular mechanism behind a number of disease‐associatedmutations. UbPred is available at http://www.ubpred.org. Proteins 2010. © 2009 Wiley‐Liss, Inc.
Dissecting the molecular mechanism of drosophila odorant receptors through activity modeling and comparative analysis
Authors: Guo Sheng , Kim Junhyong
Published: July 2009

To gain insight into the molecular mechanism of odorant receptors (ORs) in Drosophila species, we developed a Quantitative Structure Activity Relationship (QSAR) model that predicts experimentally measured electrophysiological activities between 24 D. melanogaster ORs and 108 odorants. Although the model is limited by the tested odorants,analyzing the model allowed dissection of specific topological and chemical properties necessary for an odorant to elicit excitatory or inhibitory receptor response. Linear odorants with five to eight nonhydrogen atoms at the main chain and hydrogen‐bond acceptor and/or hydrogen‐bond donor at its ends were found to stimulate strong excitatory response. A comparative sequence analysis of 90 ORs in 15 orthologous groups identified 15 putative specificity‐determining residues (SDRs) and 15 globally conserved residues that we postulate as functionally key residues. Mapping to a model of secondary structure resulted in 14 out of 30 key residues locating to the transmembrane (TM) domains. Twelve residues, including six SDRs and six conserved residues, are located at the extracellular halves of the TM domains. Combining the evidence from the QSAR modeling and the comparative sequence analysis, we hypothesize that the Drosophila ORs accept odorants into a binding pocket located on the extracellular halves of its TM domains. The QSAR modeling suggests that the binding pocket is around 15 Å in depth and about 6 Å in width. Twelve mainly polar or charged key residues, both SDRs and conserved, are located inthis pocket and postulated to distinguish docked odorants via primarily geometry fitting and hydrogen‐bond interaction. Proteins 2010. © 2009 Wiley‐Liss, Inc.
The time course of drug effects
Authors: Al‐Sallami Hesham S. , Pavan Kumar Venkata V. , Landersdorfer Cornelia B. , Bulitta Jurgen B. , Duffull Stephen B.
Published: July 2009

This review aims to introduce the concepts and principles underpinning the time course of drug effects. Models describing the time course of drug concentrations (pharmacokinetic models) and the ensuing concentration‐effect (pharmacodynamics models) as well as the linked time‐effect (pharmacokinetic‐pharmacodynamic models) are introduced. Different types of drug time‐effects models are discussed with examples which aim to explain the time course of onset, duration, and maximal effect that occurs from any given dosing schedule. These drug effects are also described in relation to disease progression models. Copyright © 2009 John Wiley & Sons, Ltd.
Characterization for water vapour barrier and heat sealability properties of heat‐treated paperboard/polylactide structure
Authors: Lahtinen Kimmo , Kotkamo Sami , Koskinen Tapio , Auvinen Sanna , Kuusipalo Jurkka
Published: July 2009

The moisture barrier and heat sealability properties of polylactide (PLA) extrusion‐coated paperboard were investigated. The first part of the study focused on the influences of coating weight and surroundings temperature and relative humidity on the water vapour transmission rate (WVTR) of the structure. The outcome arising from this part was a simple and practical equation that allows calculating the WVTR as a function of PLA coating weight under specific thermo‐hygrometric conditions. The second part of the study investigated the effect of heat treatments between 100 and 150°C on the WVTR and heat sealability of a 20 g/m2 PLA‐coated paperboard. According to the results, the lowest WVTR values achieved were about 2.5 times lower than the WVTR of the untreated structure. Presumably, the PLA coating experienced two types of reordering mechanisms: crystalline growth and packing of the amorphous structure. The greatest barrier improvement was achieved when both of these mechanisms were accumulated effectively. This was observed from the samples after a 40 min treatment at 130°C. Ultimately, the crystalline growth was experienced by PLA at 100–130°C temperatures. The packing of the amorphous section, which was also accumulated at higher temperatures, was suggested to be the decisive factor influencing WVTR. According to the heat sealing results, the heat treatments causing crystalline growth resulted in considerably increased sealing temperatures and reduced applicability of the material in high‐speed packaging applications. The treatments at 140–150°C caused only a slight increase in the sealing temperature and maintained the sealing performance of PLA. Copyright © 2009 John Wiley & Sons, Ltd.
Quantum chemical metabolism‐based simulation of carcinogenic potency of benzene derivatives
Authors: D'Yachkov Pavel N. , Kharchevnikova Nina V. , Zholdakova Zoya I. , Fjodorova Nathalia , Novich Mariana , Vrachko Marian
Published: July 2009

Using an oxenoid model, we investigated dependences of carcinogenic potency of the benzenes C6H5‐X on a nature of substituents X. According to the model, a P450 enzyme breaks a dioxygen molecule and generates the oxens, which readily react with substrates. We suggest that a stability of the intermediate OC6H6‐X with tetrahedrally coordinated C atom relative to the molecule C6H5‐X determines a rate of substrate biotransformation. Using MO LCAO MNDO approach, we calculated the total energies of molecules C6H6‐X and arene oxides OC6H6‐X. A difference ΔEminof these values determines activation energy of oxidation reaction. The compounds with the low ΔEminvalues are noncarcinogenic. Benzene derivatives with high ΔEminvalues belong to carcinogenic compounds series. The carcinogenicity of amino‐ and nitro‐substituted benzenes is also determined by N‐oxidation of amino and reduction of the nitro group. As the phenylhydroxylamines XC6H4NHOH and nitrenium ions XC6OH4NH+are the common metabolites of the nitro‐ and amino‐substituted benzenes and nitrenium ions XC6H4NH+are the ultimate carcinogens, we use the differences ΔEN=E(XC6H4NH+) −E(XC6H4NHOH) as the second parameter characterizing the carcinogenic activity of amino‐ and nitro‐substituted benzenes. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2010
Evaluation and reliability of the organic certification system: perceptions by farmers in Latin America
Authors: Albersmeier Friederike , Schulze Holger , Spiller Achim
Published: July 2009

In recent years, organic agriculture has developed rapidly, and organic certification systems are now used worldwide. However, if these standards are unable to meet their promises, their reliability will be called into question and trust in organic products will fade. As major suppliers of organic food to the European market, it is crucial for Latin American farmers to show their customers that the standards they have implemented are actually delivering what they promise. Considering the manifold resources that are being poured into these systems, it seems reasonable to critically review their reliability. A central indicator for the reliability of the system is the overall evaluation of organic certification. Therefore, it is the objective to analyse the relationship of both constructs. Findings show that most farmers are satisfied with the organic certification system and believe in its reliability; however, they fear the costs of bureaucracy and documentation. Copyright © 2009 John Wiley & Sons, Ltd and ERP Environment.
On the use of a similarity function for test case selection in the context of model‐based testing
Authors: Cartaxo Emanuela G. , Machado Patrícia D. L. , Neto Francisco G. Oliveira
Published: July 2009

Test case selection in model‐based testing is discussed focusing on the use of a similarity function. Automatically generated test suites usually have redundant test cases. The reason is that test generation algorithms are usually based on structural coverage criteria that are applied exhaustively. These criteria may not be helpful to detect redundant test cases as well as the suites are usually impractical due to the huge number of test cases that can be generated. Both problems are addressed by applying a similarity function. The idea is to keep in the suite the less similar test cases according to a goal that is defined in terms of the intended size of the test suite. The strategy presented is compared with random selection by considering transition‐based and fault‐based coverage. The results show that, in most of the cases, similarity‐based selection can be more effective than random selection when applied to automatically generated test suites. Copyright © 2009 John Wiley & Sons, Ltd.
Physical properties of MnCl2 fillers incorporated into a PVDF/PVC blend and their complexes
Authors: Abdelrazek E.M. , Elashmawi I.S. , Soliman M.A. , Aly A.
Published: July 2009

Films of a PVDF/PVC blend filled with different concentrations of MnCl2 were prepared by using a casting technique. The prepared films were investigated by different methods. X‐ray diffraction scans revealed the amorphous nature of the blend for low concentrations and a crystalline nature for higher ones. Results obtained by FTIR led to conclusions about the specific interactions in the polymer matrices and hence about the complexation. The morphological structure of the prepared samples was studied by SEM, which confirmed the results of XRD and DC electrical conductivity measurements. The ESR spectra of the samples exhibited resonance signals only after the introduction of Mn2+ ions into the blend. The DC conductivity was measured in the temperature range of 300–435 K in order to analyze the mechanism of the conduction. The conductivity–temperature plots were found to follow an Arrhenius relationship. J. VINYL ADDIT. TECHNOL., 2009. © 2009 Society of Plastics Engineers
Fabrication and characterization of in situ synthesized nano‐CaCo3‐reinforced polypropylene composite materials
Authors: Cui Yi‐Hua , Jin Xin , Shen Feng , Han Chen , Wang Jiabao
Published: July 2009

To improve the impact toughness of polypropylene (PP), nano‐CaCO3 was prepared by an in situ synthesis. The surface of the nano‐CaCO3 was modified by KH‐550 silane coupling agent and NDZ‐401 titanium acid ester coupling agent. Nano‐CaCO3/PP composite materials were fabricated through a melt‐blending method and characterized, and their mechanical properties were analyzed. The impact toughness and the tensile strength of the PP were improved significantly by the incorporation of nano‐CaCO3. When the weight fraction of nano‐CaCO3 was 2%, the maximum impact toughness and tensile strength of the PP nanocomposites were 293% and 259%, respectively, of the values for neat PP. Observation of the impact fracture surface of the nanocomposites indicated that the dispersion of nano‐CaCO3 modified by NDZ‐401 coupling agent was more homogeneous than that of nano‐CaCO3 modified by the KH‐550 silane coupling agent. J. VINYL ADDIT. TECHNOL., 2009. © 2009 Society of Plastics Engineers
Modeling of the migration of glycerol monoester plasticizers in highly plasticized poly(vinyl chloride)
Authors: Lundsgaard Rasmus , Kontogeorgis Georgios M. , Kristiansen Jørgen K. , Jensen Torkil F.
Published: July 2009

Different migration models were evaluated on the basis of data from migration experiments carried out by Danisco in 2005. The migration experiments were set up to investigate the behavior of the three plasticizers GRINDSTED®SOFT‐N‐SAFE (SNS), GRINDSTED®ACETEM 95 CO (Acetem), and epoxidized soybean oil (ESBO) with regard to their migration from three different types of poly(vinyl chloride) into isooctane at 20, 40, and 60°C. Diffusion coefficients derived from the experimental migration data were evaluated against diffusion coefficients estimated from a model based solely on the migration data for ESBO. The diffusion coefficient estimation model proved to be very good in estimating the diffusion coefficients at 20°C but overestimated them at 40°C and 60°C. By using a migration model originally derived by Kontominas [Kondyli et al., Polymer, 34, 2592 (1993)] and the estimated diffusion coefficients, it was possible to obtain a more satisfactory representation of the experimental migration data at 40°C than that obtained with the commonly used migration model of Crank [Crank, Mathematics of diffusion, (1956)] based on the experimental diffusion coefficients. J. VINYL ADDIT. TECHNOL., 2009. © 2009 Society of Plastics Engineers
A panel method free‐wake code for aeroelastic rotor predictions
Authors: Roura M. , Cuerva A. , Sanz‐Andrés A. , Barrero‐Gil A.
Published: July 2009

A panel method free‐wake model to analyse the rotor flapping is presented. The aerodynamic model consists of a panel method, which takes into account the three‐dimensional rotor geometry, and a free‐wake model, to determine the wake shape. The main features of the model are the wake division into a near‐wake sheet and a far wake represented by a single tip vortex, and the modification of the panel method formulation to take into account this particular wake description. The blades are considered rigid with a flap degree of freedom. The problem solution is approached using a relaxation method, which enforces periodic boundary conditions. Finally, several code validations against helicopter and wind turbine experimental data are performed, showing good agreement. Copyright © 2009 John Wiley & Sons, Ltd.
Hydrothermal Synthesis, Crystal Structures, and Thermal Stabilities of Two New Zinc Phosphonates with a Layered and a 3D Framework Structures
Authors: Lu Xin , Li Jing , Sun Zhen‐Gang , Dong Da‐Peng , Hua Rui‐Nian , Zhang Na , Liu Lei , Tong Fei , Wang Wei‐Nan
Published: July 2009

By using ethylenediamine as a structure‐directing agent, two new zinc phosphonates [enH2]0.5Zn[(L)(H2O)]·H2O (1) and [enH2]0.5Zn5[(HL)(L)3(H2O)2]·3H2O (2) (H3L = H2O3PCH(OH)CO2H, en = ethylenediamine), have been synthesised by hydrothermal reaction and structurally characterised by single crystal X‐ray diffraction as well as with infrared spectroscopy, elemental analysis and thermogravimetric analysis. The structure of compound 1 comprises ZnO6 octahedra and CPO3 tetrahedra connected by [O3PCH(OH)CO2]3– to form a 2D layered structure with one‐dimensional channel system along the a axis, and the protonated ethylenediamine cations are being located between two adjacent layers. In compound 2, the connections of alternately arranged ZnO6, ZnO5 polyhedra, and CPO3 tetrahedra result in a 3D framework structure with channels containing the [NH3(CH2)2NH3]2+ cations.
On the distinction between creation and conservation: a partial defence of continuous creation
Authors: MILLER TIMOTHY D.
Published: July 2009

The traditional view of divine conservation holds that it is simply a continuation of the initial act of creation. In this essay, I defend the continuous-creation tradition against William Lane Craig's criticism that continuous creation fundamentally misconstrues the intuitive distinction between creation and conservation. According to Craig, creation is the unique causal activity of bringing new patient entities into existence, while conservation involves acting upon already existing patient entities to cause their continued existence. I defend continuous creation by challenging Craig's intuitive distinction and by showing that the alternative account of creation and conservation he bases upon it is fraught with serious internal difficulties.
Property and Hunger
Authors: Sen Amartya
Published: July 2009

In an interesting letter to Anna George, the daughter of Henry George, Bernard Shaw wrote: “Your father found me a literary dilettante and militant rationalist in religion, and a barren rascal at that. By turning my mind to economics he made a man of me” (George, 1979, p. xiii). I am not able to determine what making a man of Bernard Shaw would exactly consist of, but it is clear that the kind of moral and social problems with which Shaw was deeply concerned could not be sensibly pursued without examining their economic aspects. For example, the claims of property rights, which some would defend and some (including Shaw) would dispute, are not just matters of basic moral belief that could not possibly be influenced one way or the other by any empirical arguments. They call for sensitive moral analysis responsive to empirical realities, including economic ones.
Utility-Enhancing Consumption Constraints
Authors: Levy David
Published: July 2009

The Greek poets and philosophers, united in a belief that men and women perceive the world around them very poorly, for this reason describe much of human behavior as fumbling for happiness in the dark. By contrast, perception failure is anathema to the modern tradition, as even the most innocent sort plays havoc with modern preference axioms.
In Defense of Explanatory Ecumenism
Authors: Jackson Frank , Pettit Philip
Published: July 2009

Many of the things that we try to explain, in both our common sense and our scientific engagement with the world, are capable of being explained more or less finely: that is, with greater or lesser attention to the detail of the producing mechanism. A natural assumption, pervasive if not always explicit, is that other things being equal, the more finegrained an explanation, the better. Thus, Jon Elster, who also thinks there are instrumental reasons for wanting a more fine-grained explanation, assumes that in any case the mere fact of getting nearer the detail of production makes such an explanation intrinsically superior: “a more detailed explanation is also an end in itself” (Elster 1985, p. 5). Michael Taylor (1988, p. 96) agrees: “A good explanation should be, amongst other things, as fine-grained as possible.”