bluuebunny/crossref_metadata_2025 huggingface dataset:
Methods for implementing the stream boundary condition in DSMC computations
Authors: Lilley Charles R. , Macrossan Michael N.
Published: August 2003

In the direct simulation Monte‐Carlo (DSMC) method for simulating rarefied gas flows, the velocities of simulator particles that cross a simulation boundary and enter the simulation space are typically generated using the acceptance–rejection procedure that samples the velocities from a truncated theoretical velocity distribution that excludes low and high velocities. This paper analyses an alternative technique, where the velocities of entering particles are obtained by extending the simulation procedures to a region adjacent to the simulation space, and considering the movement of particles generated within that region during the simulation time step. The alternative method may be considered as a form of acceptance–rejection procedure, and permits the generation of all possible velocities, although the population of high velocities is depleted with respect to the theoretical distribution. Nevertheless, this is an improvement over the standard acceptance–rejection method. Previous implementations of the alternative method gave a number flux lower than the theoretical number required. Two methods for obtaining the correct number flux are presented. For upstream boundaries in high‐speed flows, the alternative method is more computationally efficient than the acceptance–rejection method. However, for downstream boundaries, the alternative method is extremely inefficient. The alternative method, with the correct theoretical number flux, should therefore be used in DSMC computations in favour of the acceptance–rejection method for upstream boundaries in high‐speed flows. Copyright © 2003 John Wiley & Sons, Ltd.
Preliminary study of L‐lysine production by Bacillus species using various agricultural by‐products
Authors: Ekwealor Ikechukwu A. , Ebele Orafu A.
Published: August 2003

The production of lysine by Bacillus megaterium SP‐14 and Bacillus circulans Tx‐22 using agricultural by‐products as carbon and nitrogen sources was assessed. Among the carbon substrates used were potato, sorghum, plantain, millet, yam, cassava, and corn starches, while the nitrogen sources include cowpea, bambara‐nut, cotton seed, groundnut, soybean, and blood meals. The effect of natural nitrogen sources (1.0% w/v) and synthetic nitrogen source (4.0% w/v (NH4)2SO4) on lysine production by the Bacillus strains showed that natural nitrogen sources gave better lysine yields.
Sensory and rheological properties of Polish commercial mayonnaise
Authors: Juszczak Lesław , Fortuna Teresa , Kośla Aneta
Published: August 2003

Sensory and rheological analyses were performed to compare seven commercial mayonnaises having various fat contents and containing, or not, thickening and stabilizing agents. It was found that mayonnaise samples differed in their sensory and rheological properties. The samples with a higher fat content scored higher in sensory analysis than the low‐fat ones. The mayonnaises studied showed non‐Newtonian, pseudoplastic flow with yield stress and thixotropy. All mayonnaises, although to a different degree, exhibited a decrease in the apparent viscosity at constant shear. The mayonnaise samples which contained thickeners and stabilizers had a greater rheological stability.
Chemical composition and antioxidant test of free and glycosidically bound volatile compounds of savory (Satureja montana L. subsp. montana) from Croatia
Authors: Radonic Ani , Milos Mladen
Published: August 2003

The evaluation of antioxidant power of glycosidically bound volatile aglycones from savory shows that these compounds possess antioxidative activity comparable to that of the essential oil, but less effective compared to the well‐known antioxidant butylated hydroxytoluene (BHT) and α‐tocopherol. Thus, since the glycosides are able to release their aglycones by enzymatic hydrolysis, they could be considered as possible precursors of antioxidant substances in savory.
Determination of water‐soluble vitamins in soft drinks and vitamin supplements using capillary electrophoresis
Authors: Schreiner Matthias , Razzazi Ebrahim , Luf Wolfgang
Published: August 2003

A method for the determination of six water‐soluble vitamins based on capillary electrophoresis (CE) operated in micellar mode was developed. Thiamine hydrochloride (vitamin B1( riboflavin (vitamin B2( pyridoxine hydrochloride (vitamin B6( pantothenic acid (vitamin B5( nicotinamide (vitamin B3( and cobalamin (Vitamin B12) could be separated in a single run. All CE parameters such as buffer composition and operation temperature were optimized in order to achieve better separation. Relative standard deviations (RSDs) of the described method ranged from 1.08 to 3.68% (intra‐day precision) and 1.26 to 3.35% (inter‐day precision). The method was then used for measuring various soft drinks and vitamin supplements directly without any step of sample cleanup. The determination of niacin was successful for all samples tested, reaching recoveries near 100%. Riboflavin and pyridoxine were quantified successfully in some but not all samples. Therefore, an evaluation on a case‐by‐case basis is mandatory. When applicable, this method provides a fast, accurate, simple, and inexpensive way to quantify selected vitamins, and is therefore well suited for routine analysis in soft drink industry.
Physicochemical, rheological, and organoleptic characteristics of wheat‐fenugreek supplemented blends
Authors: Hooda Shalini , Jood Sudesh
Published: August 2003

The effect of blending of fenugreek (raw, soaked, and germinated) flour (Trigonella faenum graecum) from 5 to 20% in wheat flour on the rheological and sensory evaluation of bread, biscuit, noodle, and macroni was studied. Farinograph water absorption, dough development time, mixing tolerance index, and dough stability increased significantly with increased amount of fenugreek flour. Incorporation of fenugreek flour in wheat flour increased the protein and fat contents of blends but decreased the gluten contents. Among the supplemented blends, blends containing germinated fenugreek flour had higher protein contents (13.83–16.30%) up to 20%. Overall acceptability scores of bread, biscuit, noodles, and macroni were found highly acceptable up to 15, 10, and 20% levels, respectively.
Sample size calculations for population‐ and family‐based case‐control association studies on marker genotypes
Authors: Pfeiffer Ruth M. , Gail Mitchell H.
Published: August 2003

Most previous sample size calculations for case‐control studies to detect genetic associations with disease assumed that the disease gene locus is known, whereas, in fact, markers are used. We calculated sample sizes for unmatched case‐control and sibling case‐control studies to detect an association between a biallelic marker and a disease governed by a putative biallelic disease locus. Required sample sizes increase with increasing discrepancy between the marker and disease allele frequencies, and with less‐than‐maximal linkage disequilibrium between the marker and disease alleles. Qualitatively similar results were found for studies of parent offspring triads based on the transmission disequilibrium test (Abel and Müller‐Myhsok, 1998, Am. J. Hum. Genet. 63:664–667; Tu and Whittemore, 1999, Am. J. Hum. Genet. 64:641–649). We also studied other factors affecting required sample size, including attributable risk for the disease allele, inheritance mechanism, disease prevalence, and for sibling case‐control designs, extragenetic familial aggregation of disease and recombination. The large sample‐size requirements represent a formidable challenge to studies of this type. Genet Epidemiol 25:136–148, 2003. Published 2003 Wiley‐Liss, Inc.
Family‐based analysis of MSX1 haplotypes for association with oral clefts
Authors: Fallin M. Daniele , Hetmanski Jacqueline B. , Park Jiwan , Scott Alan F. , Ingersoll Roxann , Fuernkranz Hans A. , McIntosh Iain , Beaty Terri H.
Published: August 2003

Oral clefts, one of the most common forms of birth defects, are considered to be of complex etiology, including both genetic and environmental causes. To date, however, no particular genetic cause has been confirmed for isolated, nonsyndromic oral clefts. Previous case‐control and family‐based association studies reported an association between an intronic CA repeat of the MSX1 gene and risk for oral clefts. In this study, we identify eight single‐nucleotide polymorphisms (SNPs) in the MSX1 gene, and present genotype results for these SNPs in a set of 206 oral cleft cases and their parents. We performed single‐marker and haplotype‐based transmission disequilibrium tests (TDTs), and tested for evidence of interaction between MSX1 haplotypes and exposure to maternal smoking in the first trimester, using a case‐only approach. The haplotype TDT analyses further implicate this gene, or region, in controlling the risk for oral clefts, particularly for cleft palate. In addition, case‐only haplotype analyses suggest an interaction between variation in the MSX1 gene and exposure to maternal smoking. This study encourages further focus on the MSX1 gene region to ultimately determine specific variants predisposing to oral clefts. Genet Epidemiol 25:168–175, 2003. © 2003 Wiley‐Liss, Inc.
New developments in the employee–organization relationship
Authors: Shore Lynn M. , Coyle‐Shapiro Jacqueline A‐M.
Published: August 2003

Greater understanding of the relationship between an employee and his/her employing organization has been the goal of organizational behaviour scholars for decades. Many questions have remained unanswered, and with this view in mind, the articles in this special issue examined the employee–organization relationship (EOR) from multiple perspectives. These articles provided considerable support for social exchange as a basis for understanding the EOR in diverse cultures, for different work arrangements and at the individual, dyadic, and organizational levels of analysis. Furthermore, several articles provided empirical evidence as to the boundary conditions of social exchange as a framework for understanding the EOR. Both conceptual and empirical articles examined distinctions and similarities among exchange related constructs. This special issue extends current thinking on the employment relationship by examining the role of culture and sense making in the formation of the EOR; the value of cognitive processes in the revision and evaluation of the EOR and; the contribution of the employer's perspective to the EOR. Future research should build on this work by focusing more attention on aspects of the context as well as individual differences that may influence EORs. Finally, the employer's perspective warrants greater attention conceptually and empirically to further our understanding of the EOR as a two‐way exchange. Copyright © 2003 John Wiley & Sons, Ltd.
Java implementation of policy‐based bandwidth management
Authors: Jha S. , Hassan M.
Published: August 2003

We describe a Java implementation of a policy based bandwidth management system using the standard policy protocols and an interface to the Linux Diffserv implementation. The useful features, such as extensibility and object orientation, of the Java implementation is illustrated by directly referring to the relevant programming codes. Through two practical experiments, we demonstrate the capability of our implementation in supporting policy‐based dynamic resource allocations in enterprise networks. Copyright © 2003 John Wiley &Sons, Ltd.
Controlling unresponsive connections in an active network architecture
Authors: Prabhavalkar Niraj , Parashar Manish
Published: August 2003

This paper presents the design, implementation and evaluation of Limiting Greedy Connections (LGC), an active mechanism for controlling unresponsive connections and minimizing the degradation in network performance caused by bandwidth‐greedy applications. The primary objectives of the LGC mechanism are to limit the impact of greedy connections on a congested node, to keep a loose upper bound on the packet queue occupancy at the intermediate nodes of the network and to minimize packet loss. The LGC mechanism is evaluated for a variety of network topologies, transmitting sources and node queue parameters, using a Java‐based active network testbed. Copyright © 2003 John Wiley &Sons, Ltd.
Estimation of a pKa for Protonated Dimethoxycarbene
Authors: Guthrie J. P. , More O'Ferrall R. A. , O'Donoghue A. C. , Waghorne W. E. , Zrinski I.
Published: August 2003

A pKa is estimated for the protonation of dimethoxycarbene based on the relationship pKa = pKR −pKH2O, where KH2O and KR are equilibrium constants for hydration of the carbene and reaction of the dimethoxymethyl carbocation with water to form dimethoxymethanol, respectively. A value of pKa = 15.5 in aqueous solution is derived based on pKR = −5.7 for the carbocation and an estimate of pKH2O = −21.2 based on a heat of formation of the carbene ΔH°f = −38.8 ± 2 kcal mol−1, calculated at the G3 level in the gas phase. This value for the pKa compares satisfactorily with pKa = 11 inferred from the dependence of experimental rate constants for reaction of the carbene with alcohols and acetic acid upon the pKa of the oxygen acid in acetonitrile, taking account of the difference in solvents for the calculated and measured values. The calculated heat of formation of dimethoxycarbene in the gas phase is compared with an experimental value of −52.6 kcal mol−1 based on photoacoustic measurements of the heat of reaction of the carbene with methanol solvent to form trimethyl orthoformate. Reanalysis of the experimental data using a heat of solution of trimethyl orthoformate in methanol measured in this work suggests that the discrepancy arises in part from a difference in the heat of reaction of the carbene with methanol in solution and in the gas phase and partly (although less certainly) from a relatively high heat of solution of the carbene in methanol. Copyright © 2003 John Wiley & Sons, Ltd.
Protective effect of fenugreek (Trigonella foenum graecum) seeds in experimental ethanol toxicity
Authors: Thirunavukkarasu V. , Anuradha C. V. , Viswanathan P.
Published: August 2003

The study investigates the effect of aqueous extract of fenugreek seeds (Trigonella foenum graecum) on lipid peroxidation and antioxidant status in experimental ethanol toxicity in rats. The ability of the seed extract to prevent iron‐induced lipid peroxidation in vitro was also investigated. Ethanol feeding for 60 days resulted in signiﬁcant increases in the activities of serum aspartate transaminase, alanine transaminase and alkaline phosphatase. The levels of serum lipid hydroperoxides and thiobarbituric acid reactive substances in liver and brain were also signiﬁcantly elevated. Signiﬁcantly lower activities of superoxide dismutase, catalase, glutathione peroxidase, glutathione S‐transferase and glutathione reductase were observed in liver and brain accompanied by depletion in glutathione, ascorbic acid and α‐tocopherol concentrations. Activity of Ca2+ ATPase in brain was signiﬁcantly lowered.

Simultaneous administration of aqueous extract of fenugreek seeds with ethanol prevented the enzymatic leakage and the rise in lipid peroxidation and enhanced the antioxidant potential. The seeds exhibited appreciable antioxidant property in vitro which was comparable with that of reduced glutathione and α‐tocopherol. Further, histopathological examination of liver and brain revealed that, aqueous extract of fenugreek seeds could offer a signiﬁcant protection against ethanol toxicity. Copyright © 2003 John Wiley & Sons, Ltd.
Four glycosides from the leaves of Abeliophyllum distichum with inhibitory effects on angiotensin converting enzyme
Authors: Oh Hyuncheol , Kang Dae‐Gill , Kwon Tae‐Oh , Jang Kyu Kwan , Chai Kyu‐Yun , Yun Young‐Gab , Chung Hun‐Taeg , Lee Ho‐Sub
Published: August 2003

The bioassay‐guided fractionation of the n‐BuOH extract of Abeliophyllum distichum afforded acteoside (1), isoacteoside (2), rutin (3), and hirsutrin (4). Compounds 1–3 moderately inhibited the angiotensin I converting enzyme activity in a dose‐dependent manner. Compounds 1–3 showed the 50% inhibitory concentration values of 228 µg/mL, 290 µg/mL, and 278 µg/mL, respectively. Copyright © 2003 John Wiley & Sons, Ltd.
Interaction of some traditional plant extracts with uterine oestrogen or progestin receptors
Authors: Benie T. , Thieulant M.‐L.
Published: August 2003

Previous work has demonstrated that stem bark extracts of Combretodendron macrocarpum (Barringtoniaceae), Cola nitida (Sterculiaceae), Afrormosia laxiﬂora and Pterocarpus erinaceus (Fabaceae) blocked the oestrus cycle of female rats through antigonadotropic activity. Moreover, a study of the plant substances responsible for these effects revealed the presence of phyto‐anti‐oestrogens in these plant extracts. In order to explain the mechanism by which these substances exert their antifertility actions, the interaction of the plant extract with oestrogen and progesterone receptors was studied. All crude extracts exerted inhibition of (3H)‐oestradiol or (3H)‐Organon binding to their respective receptors but their relative afﬁnities were much lower than those of oestradiol or progesterone. Respective efﬁciencies of plant extracts in competing for the oestrogen receptor were as follows: A. laxiﬂora > P. erinaceus > C. macrocarpum > C. nitida. The efﬁciency order of competition for the progestin receptor was different to that of oestrogen. The most potent competitor was C. macrocarpum extract, followed by P. erinaceus, C. nitida and A. laxiﬂora. Moreover, the interaction between oestradiol and plant extracts with the oestrogen receptor was determined to be competitive only for C. macrocarpum and A. laxiﬂora, whereas all compounds produced a competitive inhibition on the progestin receptor binding. These results suggest that the plant extract binding site was the same site as for the steroid. These results suggest also that crude plant extracts may interfere with natural oestrogen and/or progestagen in vivo by binding to steroid receptors. Copyright © 2003 John Wiley & Sons, Ltd.
Polyphenols of Melaleuca quinquenervia leaves – pharmacological studies of grandinin
Authors: Moharram F. A. , Marzouk M. S. , El‐Toumy S. A. A. , Ahmed A. A. E. , Aboutabl E. A.
Published: August 2003

Four polyphenolic acid derivatives and three ellagitannins were isolated from the leaves of Melaleuca quinquenervia (Clav.) S. T. Blake for the ﬁrst time. Their structures were elucidated as gallic acid (1), ellagic acid (2), 3‐O‐methylellagic acid (3), 3,4,3′‐tri‐O‐methylellagic acid (4), 2,3‐O‐hexahydroxydiphenoyl‐(α/β)‐D‐4C1‐glucopyranose (5), castalin (6) and grandinin (7) on the basis of chemical, mass spectrometric (‐ve ESI‐MS) and spectroscopic (UV, 1H‐, 13C NMR, 1H,1H‐, 1H,13C‐COSY, 1H,1H‐TOCSY and HMBC) analyses. Grandinin (the major compound) showed radical scavenging properties by its reaction with 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) radical [EC50 = 4.3 ± 0.3 µg mL−1]. It was found to be relatively nontoxic in mice [LD50 = 316 mg Kg−1 b.wt.]. It exhibited a signiﬁcant dose‐dependent (35–70 mg Kg−1) hypoglycemic effect by signiﬁc‐antly reducing blood glucose level in basal condition and after heavy glucose load in normal mice. Moreover, it reduced the elevated blood glucose level in STZ‐induced diabetic mice. In addition, grandinin reduced the elevated blood urea nitrogen and serum lipid peroxides in STZ‐induced diabetic mice. Copyright © 2003 John Wiley & Sons, Ltd.
The effect of papaverine on acute opiate withdrawal in guinea pig ileum
Authors: Capasso Anna , Loizzo Alberto
Published: August 2003

In the present work the effect of papaverine, a non speciﬁc smooth muscle relaxant, was investigated on the naloxone‐precipitated withdrawal contracture of the acute morphine‐dependent guinea‐pig ileum in vitro. Furthermore, the effect of papaverine was also considered on DAGO (highly selective µ‐agonist) and U50‐488H (highly selective k‐agonist) withdrawal to test whether the possible interaction of papaverine on opioid withdrawal involves µ‐ and/or k‐opioid receptors. Following a 4 min in vitro exposure to opioid agonist, the guinea‐pig isolated ileum exhibited a strong contracture after the addition of naloxone. Papaverine treatment (1 × 10−7 − 5 × 10−7 − 1 × 10−6 M) before or after the opioid agonists was able of both preventing and reversing the naloxone‐induced contracture after exposure to µ (morphine and DAGO) or k (U50‐488H) opiate agonists in a concentration‐dependent fascion. Both acetylcholine response and electrical stimulation were not affected by papaverine treatment whereas the ﬁnal opiate withdrawal was still reduced.

The results of the present study indicate that papaverine was able to produce signiﬁcative inﬂuence on the opiate withdrawal in vitro and papaverine was able to exert its effect both at µ and k opioid agonists. Copyright © 2003 John Wiley & Sons, Ltd.
The hepatoprotective effects of Limonium sinense against carbon tetrachloride and β‐D‐galactosamine intoxication in rats
Authors: Chaung Shang‐Shing , Lin Chun‐Ching , Lin Julian , Yu Kuo‐Ho , Hsu Yu‐Fang , Yen Ming‐Hong
Published: August 2003

In the present study, the hepatoprotective action of Limonium sinense (Plumbaginaceae) was evident after carbon tetrachloride (CCl4) and β‐D‐galactosamine (D‐GalN), respectively, challenge in rats. The plant materials were divided into two parts: (1) the roots extracted with water (WRE) and (2) the leaves extracted with methanol and fractionated with chloroform (CLE). Both WRE and CLE were extremely ﬂavonoid‐enriched extracts.

In an CCl4‐induced acute liver damage study, pretreatment with WRE at 300 mg/kg i.p. and CLE at 100 mg/kg i.p. signiﬁcantly reduced the amino‐transaminases levels of SGOT (p < 0.01) and SGPT (p < 0.01) previously increased by CCl4 intoxication. In D‐GalN‐induced acute liver damage study, administration of WRE (300 and 500 mg/kg) or CLE (100 mg/kg) p.o. also signiﬁcantly reduced the SGOT (p < 0.01) and SGPT (p < 0.01) levels previously increased by D‐GalN intoxication. Furthermore, the serum triglyceride level was increased after pretreatment with WRE or CLE previously reduced by D‐GalN intoxication. All of the liver function proﬁles were conﬁrmed to have improvement of liver lesion in histopathological obsvervation.

In an acute toxicity test on ICR mice, the LD50 of WRE was 777.6 mg/kg i.p. An in vitro study showed that CLE possessed a more potent cytotoxicity to human hepatocellular carcinoma cells (Hep3B) (EC50 = 43.1 µg/mL) than the other organic fractions, which were fractionated from methanol extracts of the leaves of L. sinense. The present results conclude that L. sinense possesses a hepatoprotective efﬁcacy, and is relatively safe in rats. Copyright © 2003 John Wiley & Sons, Ltd.
Smooth muscle contraction induced by Indigofera dendroides leaf extracts may involve calcium mobilization via potential sensitive channels
Authors: Amos S. , Binda L. , Kunle O. F. , Okafor I. , Emeje M. , Akah P. A. , Wambebe C. , Gamaniel K.
Published: August 2003

The contractile effects of the aqueous extract of the leaves of Indigofera dendroides (ID) were studied on the gastrointestinal motility in mice and isolated smooth muscle preparations obtained from rats and guinea pigs. The contractile effects of 10−6 M acetylcholine, 80 mM KCl and 1.6 mg/ml ID were measured on the rat ileal smooth muscle exposed to calcium‐free buffer or physiological solution, to determine the calcium pools mobilized by extract for activation of contraction. Acute toxicity test (LD50) was also carried out in mice. The result showed that ID (0.05–3.2 mg/ml) produced a concentration‐dependent contraction of the guinea pig and rat ileum. These responses were not blocked by mepyramine (2.49 × 10−9 M), verapamil (8.14 × 10−9 M), or pirenzepine (4.7 × 10−7 M), but were blocked completely by atropine (2.92 × 10−9 M). A signi.cant increase in propulsion of gastrointestinal motility was observed. Acetylcholine, KCl and ID produced contractions in Ca2+ free media. The phasic components of the contractile responses to Ach as well as the tonic component of K+ and ID‐induced contractions were relatively resistant to short periods of calcium‐free exposure. Ach, K+ and ID still caused contractions in the presence of verapamil. The data revealed that ID‐induced contractions were not mediated by histaminergic receptors, calcium channels, M1 muscarinic receptors. It also suggests that Ach mobilize Ca from some tightly bound or intracellular pool, whereas high K+ and ID may mobilize Ca from some superficial or loosely‐bound pool. Copyright © 2003 John Wiley & Sons, Ltd.
Antifungal activity of Mahonia aquifolium extract and its major protoberberine alkaloids
Authors: Volleková Anna , Košt'álová Daniela , Kettmann Viktor , Tóth Jaroslav
Published: August 2003

The crude extract of Mahonia aquifolium (Berberidaceae) stem bark and its components berberine, palmatine and jatrorrhizine were screened for their inhibitory activity against a variety of dermatophytes and two Candida species of human origin using the in vitro dilution agar plate method. Jatrorrhizine was found to be the most effective against all fungal species tested (MIC ranges from 62.5 to 125 µg/mL), while the crude extract, berberine, and palmatine exhibited only marginal activity (MIC 500 to ≥ 1000 µg/mL). Dermatophytes were more susceptible to jatrorrhizine than yeasts, and Scopulariopsis brevicaulis appeared the least sensitive species to all the compounds tested. The effects of the alkaloids were compared with those of .uconazole and bifonazole for which the MIC ranges were 12.5 to >100 µg/mL. Our results suggest that jatrorrhizine may serve as a leading compound for further studies to develop new antifungal agents with highly potent antifungal activity and low host toxicity. Copyright © 2003 John Wiley & Sons, Ltd.
Exploring the consistency of logP estimation for substituted coumarins
Authors: Vrakas Demetris , Tsantili‐Kakoulidou Anna , Hadjipavlou‐Litina Dimitra
Published: August 2003

The lipophilicity of a series of substituted coumarins was investigated by experimental and calculative approaches. The compounds contain substituted amidoximes, or substituted heterocycles directly attached at position 4 of the coumarinic skeleton. The reliability of the predictions produced by 8 different calculation systems was evaluated considering the absolute differences and the correlation between experimental and calculated logP values. The calculation procedure based on electrotopological state indices provided better results than the fragmental and atomic contribution systems applied. The consistency of the predictions based on the fragmental or atomic contribution systems was further explored by comparing the contribution of certain structural characteristics, defined as special π constants, in the experimental and estimated logP values. Differences between the heterocyclic and the original benzene π constants were found to affect the predictions. They might be attributed to the contribution of electronic effects as further supported by the factorization of logP in bulk and electronic terms. The same factors were found to be significant for the calculated logP values derived on the basis of the Electrotopological State Indices.
3D‐QSAR and Docking Study of the Binding Mode of Steroids to Progesterone Receptor in Active Site
Authors: Chen HaiFeng , Li Qiang , Yao Xiaojun , Fan BoTao , Yuan ShenGang , Panaye A. , Doucet J. P.
Published: August 2003

Autodock 3.0 was applied to the search for the binding mode of a set of steroids with progesterone receptor (PR). The results of docking investigation show that oxygen atom of 3‐keto forms three hydrogen bonds with the residues Gln725 and Arg766 respectively. This is consistent with the reported work of S. P. Williams et al. (Nature, 1998, 393, 392–396). Moreover, we have studied in particular the most affinitive compound, steroid with a para alkylthio substituent of benzene at position 11. We find that there is a deep cavity around this substituent and a wide cavity around the substituent on position 17. This result could help us to select substituents to improve the PR‐binding affinity of steroids. The most probable aligned conformers were selected by a docking‐guided conformation selection method, and all‐orientation and all‐placement searches were applied to optimize CoMFA and CoMSIA models. Stable and highly predictive 3D‐QSAR models were built with cross‐validated coefficients q2 0.773 and 0.699 respectively for CoMFA and CoMSIA. The predictive ability of these models was validated using a test set. The results agree with those obtained from the docking investigations.
Evaluation of Vitreous and Starchy Syrian Durum (Triticum Durum) Wheat Grains: The Effect of Amylose Content on Starch Characteristics and Flour Pasting Properties
Authors: El‐Khayat Ghassan H. , Samaan Jihad , Brennan Charles S.
Published: August 2003

The physiochemical composition of durum wheat cultivars was studied in order to investigate the influence of vitreousness on the chemical composition of starch and its thermal and pasting properties. Six durum wheat lines were chosen and grown in northern Syria. Grains of each cultivar were visually sorted according to the degree of vitreousness into fully vitreous and fully starchy fractions. Amylose/amylopectin ratio and total starch was determined using Megazyme methods, while thermal and pasting properties were determined using DSC and RVA. Starchy kernels were higher in total starch than vitreous kernels but showed a decreased amylose content. Negative linear relations were found between amylose content, and both peak viscosity and breakdown. Trends in variation of gelatinisation characteristics were observed between vitreous and starchy kernels from the same cultivar, with higher total enthalpy being associated with starchy grains compared with vitreous grains of the same line.
In vivo p53 function is indispensable for DNA damage‐induced apoptotic signaling in Drosophila
Authors: Lee Jun Hee , Lee Eunji , Park Jeehye , Kim Euysoo , Kim Jaeseob , Chung Jongkyeong
Published: August 2003

p53 is a representative tumor suppressor whose dysfunction is a major cause of human cancer syndrome. Here we isolated flies lacking Dmp53, which encodes the single Drosophila orthologue of mammalian p53 family. Dmp53 null mutants well developed into adults, only displaying mild defects in longevity and fertility. However, genomic stability and viability of Dmp53 mutants dramatically decreased upon ionizing irradiation. Moreover, mutating Dmp53 abolished irradiation‐induced apoptosis and reaper induction. These results indicate that Dmp53 is a central component of DNA damage‐dependent apoptotic signaling.
Nuclear localization of liver FBPase isoenzyme in kidney and liver
Authors: Yáñez Alejandro J. , Bertinat Romina , Concha Ilona I. , Slebe Juan C.
Published: August 2003

Nuclear localization has been observed for glycolytic enzymes but not for key gluconeogenic enzymes. We report our findings on the intracellular localization of liver FBPase in rat liver and kidney, the main organs in the endogenous glucose production. Immunofluorescence and confocal analysis revealed that FBPase was present in the cytosol and, unexpectedly, inside the nucleus of hepatocytes and proximal cells of the nephron. Additionally, FBPase was found in the plasma membrane area of adjacent hepatocytes where glycogen is synthesized and in the apical region of proximal kidney cells. This subcellular distribution in multiple compartments suggests the presence of different localization signals on FBPase for diverse metabolic functions.
Cross dating (Th/U-14C) of calcite covering prehistoric paintings in Borneo
Authors: Plagnes Valérie , Causse Christiane , Fontugne Michel , Valladas Hélène , Chazine Jean-Michel , Fage Luc-Henri
Published: August 2003

We present the first application of cross-dating (Th/U measured by thermo-ionization mass spectrometry (TIMS) and 14C measured by accelerator mass spectrometry (AMS)) of calcite covering prehistoric paintings. Th/U age estimates of cave drapery range from 9800 to 27,300 yr B.P. while conventional 14C age is estimated between 9900 and 7610 yr B.P. depending on the dead carbon correction. The age discrepancy is attributed to a disturbance of Th/U and/or 14C geochemical systems, showing the limits of the geochronological approach applied to this kind of material. For the Th/U system, the poor consistency of U data (U content, 234U/238U activity ratios) and apparent ages argue for open system conditions. For 14C system, variation of the dead carbon fraction (dcf) and a possible mixing of successive generations of calcite could account for age discrepancy. Nevertheless, one sample shows concordant ages for the two methods. Compatible ages through corrections for open system conditions are assumed for other samples. Then, the cross-dating suggests 9900 yr as the minimum age of the piece of drapery; the underlying painting must be older. This study of rock art demonstrates the presence of a Pleistocene population before 9900 yr in the southeast of Borneo, whereas previously the only population in evidence in this area was of Austronesian type from ∼5000 to 6000 yrs ago.
The effects of therapeutic vs. high‐intensity ultrasound on the rabbit growth plate
Authors: Lyon Roger , Liu Xue C. , Meier Joshua
Published: August 2003

Six of 6‐week‐old NZ rabbits underwent ultrasound treatment using a therapeutic dose (0.5 W/cm) and other six were treated with a higher dose (2.2 W/cm2) to the lateral aspect of the left knee joint for 20 min per day and a total of six weeks. The right knee joint served as a control. The goal of this study is to see if the therapeutic dose and high dose (approximately 45‐fold therapeutic dose) will have toxic effects on the physis. Histological review appeared normal growth plate in the therapeutic group. In the high dosage group three of six cases displayed flattening of the distal femoral epiphysis and wedging of the proximal tibial plateau and indistinct growth plate lines. It is of interest to note that there are opening radiolucent area in the lateral aspect on the femoral metaphysis in five of six cases, where bone resorption has taken place. Histological results showed that there are disordered arrays of the cartilaginous cells in the proliferative zone. The height of the lateral physis in the high dose group is not only greater than that in the therapeutic dose (1083.8 vs. 500.3 μm), but also greater than that in their contralateral control (530.7 μm) (P < 0.05). This short‐term study demonstrates that high dose ultrasound has profound pathologic effects in growing bone. Therapeutic doses of ultrasound do not have an adverse effect on bone growth in the short‐term follow‐up. © 2003 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved.
Extracorporeal shock wave therapy for plantar fasciitis. A double blind randomised controlled trial
Authors: Speed C. A. , Nichols D. , Wies J. , Humphreys H. , Richards C. , Burnet S. , Hazleman B. L.
Published: August 2003

Background: Extracorporeal shock wave therapy (ESWT) is an increasingly popular therapeutic approach in the management of a number of tendinopathies. Benefit has been shown in calcific tendinitis of the rotator cuff, but evidence for its use in non‐calcific disorders is limited.

Aims: To perform a double blind randomised controlled trial of moderate dose shock wave therapy in plantar fasciitis.

Methods: Adults with plantar fasciitis for at least 3 months were randomised to receive either active treatment (0.12 mJ/mm) or sham therapy, monthly for 3 months. Pain in the day, nocturnal pain and morning start‐up pain were assessed at baseline, before each treatment and 1 and 3 months after completion of therapy.

Results: Eighty‐eight subjects participated and no differences existed between the groups at baseline. At 3 months, 37% of the subjects in the ESWT group and 24% in the sham group showed a positive response (50% improvement from baseline) with respect to pain. Positive responses in night pain occurred in 41% and 31% in the ESWT and sham groups, respectively. Positive responses in start‐up pain occurred in 37% and 36% in the ESWT and sham groups, respectively. Both groups showed significant improvement over the course of the study, but no statistically significant difference existed between the groups with respect to the changes were seen in any of the outcome measures over the 6‐month period.

Conclusions: There appears to be no treatment effect of moderate dose ESWT in subjects with plantar fasciitis. Efficacy may be highly dependent upon machine types and treatment protocols. Further research is needed to develop evidence based recommendation for the use ESWT in musculoskeletal complaints. © 2003 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved.
PGE2 and IL‐6 production by fibroblasts in response to titanium wear debris particles is mediated through a Cox‐2 dependent pathway
Authors: Bukata Susan V. , Gelinas Jill , Wei Xiaochao , Rosier Randy N. , Puzas J. Edward , Zhang Xinping , Schwarz Edward M. , Song Xiao‐yu R. , Griswold Don E. , O'Keefe Regis J.
Published: August 2003

Aseptic loosening of orthopaedic implants is precipitated by wear debris‐induced osteolysis. Central to this process are the pro‐inflammatory mediators that are produced in response to wear by the fibroblastic cells, which comprise the majority of periprosthetic membranes. Since this pro‐inflammatory cascade is mediated by a plethora of factors with redundant functions, it is imperative to establish a hierarchy. Two well‐known fibroblast derived pro‐inflammatory factors that stimulate wear debris‐induced osteoclastic resorption are prostaglandin E2 (PGE2) and IL‐6. However, their relationship to each other in this process is poorly defined. Here we show immunohistochemistry of retrieval membranes indicating that COX‐2 is the principal cyclooxygenase responsible for PGE2 production in fibroblasts around failed implants. We also performed in vitro experiments with fibroblasts derived from wild‐type (WT), COX‐1 (–/–) and COX‐2 (–/–) mice, which demonstrated that COX‐2 is required for Ti wear debris‐induced PGE2 production. Interestingly, COX‐2 was also required for IL‐6 production in these assays, which could be rescued by the addition of exogenous PGE2 (10−6 M). Pharmacology studies that utilized the COX‐1 selective inhibitor SC 560, the COX‐2 selective inhibitor celecoxib, and the nonselective COX inhibitor indomethacin confirmed these results. Taken together, these results indicate that selective inhibition of prostaglandin signaling could favorably impact aseptic loosening beyond its direct effects on PGE2 synthesis, in that it inhibits downstream pro‐inflammatory/pro‐osteoclastic cytokine production. © 2003 Orthopaedic Research Society. Published by Elsevier Ltd. All rights reserved.
Lamb waves in the lower thermosphere: Observational evidence and global consequences
Authors: Forbes J. M. , Palo S. E. , Zhang X. , Portnyagin Yu. I. , Makarov N. A. , Merzlyakov E. G.
Published: August 2003

Meteor radar observations of hourly neutral meridional winds at 95 km altitude near 88°S and along the four meridians 0°, 90°E, 90°W, and 180°, were made from Amundsen‐Scott Station at South Pole from January 19, 1995, through January 26, 1996, and from November 21, 1996, through January 27, 1997. These data reveal the existence of ±5–15 m s−1 oscillations with periods between about 7.5 and 10.5 h, propagating to the west with zonal wavenumber s = 1. These oscillations are interpreted as the atmospheric manifestations of gravitational normal modes or “Lamb” waves. Barring significant Doppler‐shifting effects, the second symmetric mode with period near 8.6 hours, and the first asymmetric mode with period near 10.4 hours, appear to dominate. At middle latitudes, for limited duration time series, it would be easy to confuse these waves with terdiurnal (8 hours) and semidiurnal (12 hours) solar tides. The Global Scale Wave Model (GSWM) is used to simulate the global perturbation temperature and wind fields consistent with these observations. Wind and temperature oscillations exceeding 12 m s−1 and 12 K, and 80 m s−1 and 40 K, are predicted to occur for the 10.4‐hour and 8.6‐hour waves, respectively, above 110 km. Such perturbations may be observable by incoherent scatter radars now in existence.
Beam‐induced electron modulations observed during TSS 1R
Authors: Rubin A. G. , Burke W. J. , Gough M. P. , Machuzak J. S. , Gentile L. C. , Huang C. Y. , Hardy D. A. , Thompson D. C. , Raitt W. J.
Published: August 2003

We report on modulations of electron fluxes at megahertz frequencies measured by the Shuttle Potential and Return Electron Experiment (SPREE) during fast pulsed electron gun (FPEG) beam experiments conducted after the tether break event of the Tethered Satellite System Reflight. Six intervals of sustained modulations were identified while FPEG emitted a 100 mA beam of 1 kev electrons. During five events the beam pitch angle αB was near 90° and the modulations were near even or odd half harmonics of the electron gyrofrequency ƒce. In the sixth event with 60° ≥ αB ≥ 45°, electron modulations were near estimated values of the electron plasma frequency ƒpe and 2ƒpe. Whenever SPREE detected beam electrons modulated at a given frequency, secondary electrons were also modulated at the same frequency over a broad range of energies. Occasionally, some secondary electrons were modulated simultaneously at a second frequency. Multiple frequencies were related as ratios of low integers. In one case the beam electrons were simultaneously modulated at 0.8 MHz and 1.25 kHz. SPREE measurements suggest that the beam electrons propagate in cylindrical shells whose inner edge is marked by steep spatial gradients in fluxes at 1 keV [Hardy et al., 1995]. Inside the shell, electron distribution functions have positive slopes ∂ƒ/∂v⊥ > 0 at velocities near that of the beam. Velocity space gradients act as free‐energy sources to drive cavity modes that alter the instantaneous guiding centers of electrons causing SPREE to sample alternating parts of the beam cylinder's inner edge. Associated time‐varying electric fields also modulated the fluxes of secondary electrons reaching SPREE. Other cavity modes may be excited through nonlinear processes [Calvert, 1982], With αB far from 90°, electrons in the beam cylinder evolved toward bump‐on‐tail distributions to excite large‐amplitude Langmuir modulations at ƒpe and its harmonics [Klimas, 1983]. Low‐frequency modulations are attributed to electron interactions with ion acoustic‐like waves generated as the beam moved across magnetic field lines in the ionosphere at supersonic speeds.
Identifying nonlinear wave interactions in plasmas using two‐point measurements: A case study of Short Large Amplitude Magnetic Structures (SLAMS)
Authors: de Wit T. Dudok , Krasnosel'skikh V. V. , Dunlop M. , Lühr H.
Published: August 2003

Two fundamental quantities for characterizing nonlinear wave phenomena in plasmas are the spectral energy transfer associated with the energy redistribution between Fourier modes, and the linear growth rate. It is shown how these quantities can be estimated simultaneously from dual‐spacecraft data using Volterra series models. We consider magnetic field data gathered upstream the Earth's quasiparallel bow shock, in which Short Large Amplitude Magnetic Structures (SLAMS) supposedly play a leading role. The analysis attests the dynamic evolution of the SLAMS and reveals an energy cascade toward high‐frequency waves. These results put constraints on possible mechanisms for the shock front formation.
Effect of hot oxygen on thermospheric O I UV airglow
Authors: Hubert B. , Gérard J.‐C. , Cotton D. M. , Bisikalo D. V. , Shematovich V. I.
Published: August 2003

The role of nonthermal oxygen atoms in the vertical distribution of the O I 989 Å EUV multiplet intensity is investigated using a thermospheric radiative transfer code. The superthermal oxygen concentration and temperatures are derived from the energy distribution functions of the O(3P) atoms calculated by a Monte Carlo stochastic model, and their effect on UV radiative transfer is compared to sounding rocket observations. The calculated intensity increase associated with the perturbation of the Doppler profile by the presence of hot O(3P) atoms is shown to be insufficient to account for the set of sounding rocket EUV intensity data.
Proton ring current pitch angle distributions: Comparison of simulations with CRRES observations
Authors: Chen Margaret W. , Roeder James L. , Fennell Joseph F. , Lyons Larry R. , Lambour Richard L. , Schulz Michael
Published: August 2003

In this study we compare the proton pitch angle distributions (PADs) in the ring current region (L ∼ 3–4) obtained from Combined Release and Radiation Effects Satellite (CRRES) observations during the large magnetic storm (minimum Dst = −170 nT) on August 19, 1991, with results of phase‐space mapping simulations in which we trace the bounce‐averaged drift of protons during storm‐associated enhancements in a model of the convection electric field. We map the phase‐space density ƒ according to Liouville's theorem except for attenuation by charge exchange, which we compute for both an empirical model [Rairden et al., 1986] and a theory‐based model [Hodges, 1994] of the neutral H density distribution. We compare simulated pitch angle distributions at 48 keV, 81 keV, and 140 keV at L = 3 and L = 4 directly with the CRRES distributions at the same energies and L values before and during the storm. A steady‐state application of our transport model, using the empirical neutral H density model of Rairden et al. [1986], reproduces the absolute intensities well except for E = 140 keV at L = 3 (M = 10 MeV/G) and E = 48 keV at L = 4 (M = 13 MeV/G). The anisotropies (A ∼ 0.2–0.8) of the CRRES and modeled pre‐storm pitch angle distributions agree within factors ≲ 2. Time‐dependent application of our transport model reproduces measured recovery phase anisotropies (t = 10–12 h after storm onset; A ∼ 0.4–1.2) similarly well at the selected energies and L values, but agreement between modeled and measured absolute intensities is energy‐dependent and not consistently good. Our model underpredicts the proton intensities found by CRRES for E > 80 keV at L = 4 in early recovery phase (t = 10–12 h). Perhaps the impulsive stormtime convection electric field was stronger during the main phase than we have assumed here. Comparisons were more difficult in late recovery phase (t = 20 h) because CRRES was too far off the magnetic equator. Proton life‐times inferred from the CRRES data during the recovery phase of this storm are considerably shorter than charge‐exchange lifetimes for either model, but the empirical neutral H density model of Rairden et al. [1986] leads to smaller discrepancies with the CRRES data at all the selected energies and L values than the theory‐based neutral H density model of Hodges [1994] for parameters that most closely represent the seasonal and solar maximum conditions of the August 19, 1991, storm. It appears that charge exchange alone is not enough to explain the observed rapid decay of the ring current proton intensities during the recovery phase of this storm.