bluuebunny/crossref_metadata_2025 huggingface dataset:
Changing medical doctor productivity and its affecting factors in rural China
Authors: Martineau Tim , Gong Youlong , Tang Shenglan
Published: May 2004

Using the data collected from the health facility‐based survey, part of the national health service survey conducted in 1993 and 1998, this paper tries to examine changes in labour productivity among the county‐level hospitals and township health centres in rural China, and to analyse factors affecting the changes. The results presented in the paper show that the average number of outpatient visits per doctor per day and the average number of inpatient days per doctor per day declined significantly over the period from 1986 to 1997. The main factors resulting in the reduction of productivity are associated with the increase of inappropriate staff recruitment in these health facilities, the significant decline of rural population covered by health insurance, particularly rural cooperative medical schemes (CMS), and the rapid rise of health care costs. The latter two factors also have brought about a reduction in the use of these health facilities by the rural population. The paper suggests that the government should tighten up the entrance of health and non‐health staff into the rural health sector and develop effective measures aimed to avoid providing pervasive financial incentives to the over‐provision of services and over‐use of drugs. In addition, other measures that help to increase the demand for health services, such as the establishment of rural health insurance, should be considered seriously. Copyright © 2004 John Wiley & Sons, Ltd.
Expanding self‐help group participation in culturally diverse urban areas: Media approaches to leveraging referent power
Authors: Humphreys Keith , Macus Sue , Stewart Eric , Oliva Elizabeth
Published: May 2004

Accumulating research attests to the benefits of self‐help groups for people who have various chronic health problems. Expansion of self‐help group participation may enable a broader portion of society to experience these health benefits. The Media and Education for Self‐Help (MESH) Project was an effort to increase interest in health‐related self‐help groups among middle‐ and lower‐income people in two California urban areas with minority–majority populations. A diverse coalition of self‐help group leaders designed English‐ and Spanish‐language radio public service announcements and posters that were disseminated in Oakland and Los Angeles. The outcome measures in each urban area were self‐help‐group‐related telephone inquiries to local information and referral agencies (English and Spanish language) and the number of individuals attending self‐help groups at agencies hosting many groups. Telephone caller data were also gathered in a nonintervention control urban area (Sacramento). Los Angeles experienced an overall increase in telephone calls about self‐help groups during the MESH intervention, whereas the control urban area had no change in the number of telephone calls over the same period. The initial sharp increase in self‐help‐group‐related telephone calls was not sustained in Oakland, however. The number of Spanish‐language calls about self‐help groups increased 821% in Los Angeles and 149% in Oakland in the period from the 6 months that preceded the project through the first 6 months of the MESH Project. In the MESH Project urban areas, the number of visits to self‐help groups was significantly higher in intervention months than in the same calendar months of the preceding year, particularly in Oakland, where the increase exceeded 300 visits to self‐help groups per month. These intriguing findings are discussed in terms of their health policy and program evaluation implications. © 2004 Wiley Periodicals, Inc. J Comm Psychol 32: 413–424, 2004.
A qualitative examination of the implementation of a community–academic coalition
Authors: Boydell Katherine M. , Volpe Tiziana
Published: May 2004

Many recent grant initiatives have mandated coalition building as a key component of their health promotion efforts. Health service leaders are increasingly representing their organizations on coalitions and need to better understand the complexities involved in their creation and management. In this paper we focus on the implementation of a community–academic alliance using an ethnographic approach involving participant observation and in‐depth interviews. Analysis of the data revealed five essential dimensions to be considered in the development of successful community–academic alliances: membership, structure, leadership, communication, and funding. Within each of these areas, facilitators and barriers to successful coalition building were identified. While these areas are not new, obtaining the perspective of coalition members directly adds to our understanding of the member experience in the process of implementing such initiatives. This example of a community–academic collaboration presents one model of how to minimize the distance between research and service and move toward a partnership between these two worlds. © 2004 Wiley Periodicals, Inc. J Comm Psychol 32: 357–374, 2004.
Supported socialization for people with psychiatric disabilities: Lessons from a randomized controlled trial
Authors: Davidson Larry , Shahar Golan , Stayner David A. , Chinman Matthew J. , Rakfeldt Jaak , Tebes Jacob Kraemer
Published: May 2004

Two hundred and sixty people with psychiatric disabilities who were socially isolated and withdrawn were randomly assigned to one of three conditions to facilitate their engagement in social and recreational activities: They were (a) not matched with a volunteer partner (N= 70), (b) matched with a volunteer partner who had a personal history of psychiatric disability (N= 95), or (c) matched with a volunteer partner with no history of psychiatric disability (N= 95). Participants and volunteers received a $28 stipend each month to cover the expenses of their activities. Comprehensive assessments of symptoms, functional impairment, self‐esteem, and satisfaction were made at baseline, after 4 months, and after 9 months. While all participants appeared to improve in terms of symptom reduction and increases in functioning and self‐esteem, differences between conditions were found only when participants' degree of contact with their partner was considered. While participants assigned to the nonconsumer volunteer partner condition improved in terms of their social functioning and self‐esteem when meeting with their partners, those who were assigned to consumer partners only improved when they did not. Findings highlight the important role of participants' expectations and perceptions in designing and evaluating psychosocial interventions for people with psychiatric disabilities. © 2004 Wiley Periodicals, Inc. J Comm Psychol 32: 453–477, 2004.
Expression of phospholipase C beta family isoenzymes in C2C12 myoblasts during terminal differentiation
Authors: Faenza Irene , Bavelloni Alberto , Fiume Roberta , Santi Patrizia , Martelli Alberto M. , Maria Billi Anna , Rita Lo Vasco Vincenza , Manzoli Lucia , Cocco Lucio
Published: May 2004

In the present work, we have analyzed the expression and subcellular localization of all the members of inositide‐specific phospholipase C (PLCβ) family in muscle differentiation, given that nuclear PLCβ1 has been shown to be related to the differentiative process. Cell cultures of C2C12 myoblasts were induced to differentiate towards the phenotype of myotubes, which are also indicated as differentiated C2C12 cells. By means of immunochemical and immunocytochemical analysis, the expression and subcellular localization of PLCβ1, β2, β3, β4 have been assessed. As further characterization, we investigated the localization of PLCβ isoenzymes in C2C12 cells by fusing their cDNA to enhanced green fluorescent protein (GFP). In myoblast culture, PLCβ4 was the most expressed isoform in the cytoplasm, whereas PLCβ1 and β3 exhibited a lesser expression in this cell compartment. In nuclei of differentiated myotube culture, PLCβ1 isoform was expressed at the highest extent. A marked decrease of PLCβ4 expression in the cytoplasm of differentiated C2C12 cells was detected as compared to myoblasts. No relevant differences were evidenced as regards the expression of PLCβ3 at both cytoplasmatic and nuclear level, whilst PLCβ2 expression was almost undetactable. Therefore, we propose that the different subcellular expression of these PLC isoforms, namely the increase of nuclear PLCβ1 and the decrease of cytoplasmatic PLCβ4, during the establishment of myotube differentiation, is related to a spatial‐temporal signaling event, involved in myogenic differentiation. Once again the subcellular localization appears to be a key step for the diverse signaling activity of PLCβs. © 2004 Wiley‐Liss, Inc.
A low dose of daidzein acts as an ERβ‐selective agonist in trabecular osteoblasts of young female piglets
Authors: de Wilde Anne , Lieberherr Michele , Colin Colette , Pointillart Alain
Published: May 2004

The role of estrogens and estrogen‐like molecules, including isoflavones, in regulating bone cell activities is essential in understanding the etiology and treatment of post‐menopausal osteoporosis. Although estrogen replacement (HRT) has been the main therapy used to prevent and treat osteoporosis, there are concerns about its safety. Isoflavones have attracted attention to their potential roles in osteoporosis prevention and treatment. We have compared the effects of the isoflavone daidzein (1 nM), which has no effect on tyrosine kinases, and 17β‐estradiol (1 nM) on the development and function of cultured osteoblasts isolated from long bones of young female piglets. Daidzein increased ALP activity, osteocalcin secretion, and mineralization, while E2 increased only ALP activity. The content of ERβ and osteoprotegerin secretion by control cells gradually increased during osteoblast differentiation, whereas the ERα and RANK‐L content decreased. Daidzein enhanced only the nuclear ERβ whereas estradiol increased both ERα and ERβ. Daidzein and estradiol increased osteoprotegerin and RANK‐L secretion. Daidzein had a more pronounced effect than did estradiol. Daidzein and estradiol increased the membrane content of RANK‐L and the nuclear content of runx2/Cbfa1. Daidzein enhanced the nuclear content of progesterone and vitamin D receptors but not as much as did estradiol. All the effects of daidzein were blocked by ICI 182,780. We conclude that a low concentration of daidzein may exert its anti‐resorptive action by increasing the activity of porcine mature osteoblasts via ERβ, by regulating runx2/Cbfa1 production, and by stimulating the secretion of key proteins involved in osteoclastogenesis, such as osteoprotegerin and RANK‐ligand. © 2004 Wiley‐Liss, Inc.
Decreased expression of β1‐integrin and focal adhesion kinase in epithelial cells may initiate involution of mammary glands
Authors: McMahon Christopher D. , Farr Vicki C. , Singh Kuljeet , Wheeler Thomas T. , Davis Stephen R.
Published: May 2004

The mechanisms regulating involution of mammary glands after weaning are not clear, but engorgement with milk is a key trigger. Many cell types require to be anchored to an extracellular matrix (ECM) as a prerequisite for survival and this is achieved via intregrins binding to specific motifs and signalling their attachment, intracellularly, via focal adhesion kinase (FAK). We sought to determine firstly, if expression of β1‐integrin and FAK is reduced during the first stage of involution. Expression of β1‐integrin and FAK was significantly reduced at 6 h after sealing teats and this was accompanied with a decreased abundance of cytochrome C in mitochondria. Secondly, we sought to determine if expression of β1‐integrin and FAK was restored during the first, partially reversible stage of involution (at 24 h), but not during the second irreversible stage, which occurs after 72 h. Re‐suckling restored full expression of the 80 kDa fragment of FAK, but not of the 125 kDa protein or β1‐integrin at 24 h after weaning. Re‐suckling did not restore expression of either peptide after 72 h. Changes in expression of cytochrome C and pro‐caspase‐3 (apoptotic markers) were similar to that of the 80 kDa fragment of FAK. These data suggest that epithelial cells can restore partial contact with their basement membrane during the first, reversible stage, but not during the second irreversible stage of involution. We speculate that decreased contact between epithelial cells and their basement membrane initiates apoptosis in mammary glands at weaning. This process begins within 6 h of pup withdrawal. © 2004 Wiley‐Liss, Inc.
Calpain inhibitor 2 prevents axonal degeneration of opossum optic nerve fibers
Authors: Araújo Couto Luciana , Sampaio Narciso Marcelo , Hokoç Jan Nora , Blanco Martinez Ana Maria
Published: May 2004

The ultrastructural change that characterizes the onset of Wallerian degeneration is the disintegration of axoplasmic microtubules and neurofilaments, which are converted into an amorphous and granular material, followed by myelin breakdown. The mechanism underlying such processes is an increase in the amount of intracellular calcium, leading to activation of proteases called calpains. The aim of this study was to evaluate by quantitative ultrastructural analysis whether nerve fibers can be preserved by the use of an exogenous inhibitor of these proteases (calpain inhibitor‐2, Mu‐F‐hF‐FMK), after optic nerve crush. For that, the left optic nerves of opossums, Didelphis aurita, were crushed with the aid of a fine forceps, and half of them received a calpain inhibitor mixed with Elvax resin. Ninety‐six hours after the lesion, the animals were reanesthetized and transcardially perfused, and the optic nerves were removed, the right ones being used as normal nerves. Afterward, the optic nerves were dissected and processed for routine transmission electron microscopy and quantitative and statistical analysis. The results of this analysis showed that the group that received the calpain inhibitor presented a reduction of astrogliosis, maintaining the optic nerve structure in an organized state; a significant decrease in the number of degenerating fibers; and a significant increase in the number of fibers with preserved cytoskeleton and preservation of axonal and myelin area and integrity, reducing the enlargement and edema of the axon. In conclusion, our findings suggest that calpain inhibitor is able to provide neuroprotection of the central nervous system fibers after a crush lesion. © 2004 Wiley‐Liss, Inc.
Molecular Dynamics Simulations of Polymer Translocations
Authors: Randel Richard , Loebl Hannah C. , Matthai Clarence C.
Published: May 2004

Summary: Molecular dynamics simulation studies of the translocation of charged homopolymers of length, N, driven by an electric potential gradient through a channel have been performed. We find that the translocation time, τ, displays an inverse power dependence on the temperature of the simulation τ ∼ (T − T0)−7/4, which is in very good agreement with experimental results. In addition, the dependence of τ on the driving field strength and the velocity of translocation on the polymer length N have also been obtained. The results suggest that such minimalist models are useful in modelling biological processes and that the molecular dynamics method is a suitable approach for carrying out these simulations.

Snapshot of the polymer during the simulation.

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Snapshot of the polymer during the simulation.
Polymer Melt Intercalation in Clay Modified by Diblock Copolymers
Authors: Kudryavtsev Yaroslav V. , Govorun Elena N. , Litmanovich Arkady D. , Fischer Hartmut R.
Published: May 2004

Summary: The thermodynamic equilibrium in a melt of homopolymer C mixed with clay modified by a diblock copolymer AB is considered in theory. It is assumed that mixing is carried out in two stages. At first, the diblock copolymer penetrates into the interlayers formed by long clay sheets. Then, the clay with adsorbed diblock copolymer chains is added to the homopolymer melt. It is shown that the first process is thermodynamically favorable only if the interlayer width exceeds some threshold value that depends mostly on the difference in the adsorption energy of units A and B. A spontaneous mixing at the second stage is possible only if the enthalpic interactions between homopolymer and copolymer units are not very unfavorable. If so, the formation of an intercalated state is expected for a homopolymer of length comparable to the copolymer length, while for a long homopolymer the anticipated equilibrium state is exfoliation. The spatial distribution of A, B, and C units across the interlayer has been studied for different parameters of the system. The most readily adsorbing units A occupy almost all clay surface. However, the layer of block A is considerably swelled by both B and C units. The mutual distribution of units B and C may vary from almost homogeneous to having rather sharp boundary depending on the value of the Flory‐Huggins parameter χBC. The formation of a pure homopolymer layer at the center of the interlayer indicates about a tendency to exfoliate.

Interlayer profiles of the fractions of units A, B, and C, respectively.

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Interlayer profiles of the fractions of units A, B, and C, respectively.
Silibinin inhibits the invasion of human lung cancer cells via decreased productions of urokinase‐plasminogen activator and matrix metalloproteinase‐2
Authors: Chu Shu‐Chen , Chiou Hui‐Ling , Chen Pei‐Ni , Yang Shun‐Fa , Hsieh Yih‐Shou
Published: May 2004

Cancer metastasis, involving multiple processes and various cytophysiological changes, is a primary cause of cancer death and may complicate the clinical management, even lead to death. Silibinin is a flavonoid antioxidant and wildly used for its antihepatotoxic properties and recent studies have revealed pleiotropic anticancer and antiproliferative capabilities of silibinin. In this study, we first observed that silibinin exerted a dose‐ and time‐dependent inhibitory effect on the invasion and motility, but hardly on the adhesion, of highly metastatic A549 cells in the absence of cytotoxicity. To look at the precise involvement of silibinin in cancer metastasis, A549 cells were treated with silibinin at various concentrations, up to 100 μM, for a defined period and then subjected to gelatin zymography, casein zymography and Western blot to investigate the impacts of silibinin on metalloproteinase‐2 (MMP‐2), urokinase plasminogen activator (u‐PA), and tissue inhibitor of metalloproteinase‐2 (TIMP‐2), respectively. The results showed that a silibinin treatment may decrease the expressions of MMP‐2 and u‐PA in a concentration‐ and time‐dependent manner and enhance the expression of TIMP‐2. Further analysis with semi‐quantitative RT‐PCR showed that silibinin may regulate the expressions of MMP‐2 and u‐PA on the transcriptional level while on the translational or post‐translational level for TIMP‐2. © 2004 Wiley‐Liss, Inc.
Aeroelastic forces and dynamic response of long‐span bridges
Authors: Lazzari Massimiliano , Vitaliani Renato V. , Saetta Anna V.
Published: May 2004

In this paper a time domain approach for predicting the non‐linear dynamic response of long‐span bridges is presented. In particular the method that leads to the formulation of aeroelastic and buffeting forces in the time domain is illustrated in detail, where a recursive algorithm for the memory term's integration is properly developed. Moreover in such an approach the forces' expressions, usually formulated according to quasi‐static theory, have been substituted by expressions including the frequency‐dependent characteristics. Such expressions of aeroelastic and buffeting forces are made explicit in the time domain by means of the convolution integral that involves the impulse functions and the structural motion or the fluctuating velocities. A finite element model (FEM) has been developed within the framework of geometrically non linear analysis, by using 3‐d degenerated finite element. The proposed procedure can be used to analyze both the flutter instability phenomenon and buffeting response. Moreover, working in the geometrically non‐linearity range, it verifies the possibility of strongly flexible structures of actively resisting the wind loading. Copyright © 2004 John Wiley & Sons, Ltd.
Alkoxylation of epoxidized polyisoprene by opening of oxirane rings with alcohols
Authors: Challioui Allal , Derouet Daniel , Oulmidi Abdelkader , Brosse Jean Claude
Published: May 2004

Alkoxylation of epoxidized polyisoprene catalyzed by cerium ammonium nitrate (CAN) was achieved under very mild conditions both in melt and in solution. The cleavage of the epoxidized units with alcohols leads to the formation of alkoxyalcohol units and epoxide rearrangement units in the case of 20 and 38 % epoxidized 1,4‐polyisoprenes. For higher percentage of epoxidation (72 %), cyclization of epoxidized units is observed, which dramatically reduces the alcohol grafting percentage onto the polymer chains. The glass transition temperature increase with the percentage of alkoxylation is attributed to both alkoxy and hydroxyl groups formed after the ring opening of the epoxidized units. However, size‐exclusion chromatography analysis of the modified polymers showed a decrease in the number‐average molecular weight and an increase in the weight‐average molecular weight, which can be interpreted as the degradation and crosslinking of the polymer chains, respectively. Copyright © 2004 Society of Chemical Industry
Thermoresponsive behaviour in aqueous solution of poly(maleic acid‐alt‐vinyl acetate) grafted with poly(N‐isopropylacrylamide)
Authors: Vasile Cornelia , Bumbu Gina‐Gabriela , Mylonas Ioannis , Bokias Georgios , Staikos Georgios
Published: May 2004

The synthesis of a thermoresponsive graft copolymer consisting of a maleic acid/vinyl acetate alternating copolymer backbone (MAc‐alt‐VA) and poly(N‐isopropylacrylamide) (PNIPAM) side chains is reported. Turbidimetric measurements in dilute aqueous solutions showed that no macroscopic phase separation takes place when the temperature is raised above the lower critical solution temperature (LCST) of PNIPAM, even at pH = 2. Moreover, in semi‐dilute aqueous solutions, a pronounced thermally induced viscosity increase (thermothickening) was observed. This thermoresponsive behaviour has been attributed to the interconnection of the hydrophilic MAc‐alt‐VA graft copolymer backbones by means of the hydrophobic PNIPAM side chain aggregates formed as the temperature increases above the LCST of this polymer. Copyright © 2004 Society of Chemical Industry
Ring‐opening polymerization of D,L‐lactide by rare earth 2,6‐dimethylaryloxide
Authors: Zhang Lifang , Shen Zhiquan , Yu Cuiping , Fan Ling
Published: May 2004

Ring‐opening polymerization of D,L‐lactide (LA) has been successfully carried out by using rare earth 2,6‐dimethylaryloxide (Ln(ODMP)3) as single component catalyst or initiator for the first time. The effects of different rare earth elements, solvents, monomers and catalyst concentration as well as polymerization temperature and time on the polymerization were investigated. The results show that La(ODMP)3 exhibits higher activity to prepare poly(D,L‐lactide) (PLA) with a viscosity molecular weight of 4.5 × 104 g mol−1 and the conversion of 97 % at 100 °C in 45 min. The catalytic activity of Ln(ODMP)3 has following sequence: La > Nd > Sm > Gd > Er > Y. A kinetic study has indicated that the polymerization is first order with respect to both monomer and catalyst concentration. The apparent activation energy of the polymerization of LA with La(ODMP)3 is 69.6 kJ mol−1. The analyses of polymer ends indicate that the LA polymerization proceeds according to ‘coordination–insertion’ mechanism with selective cleavage of the acyl–oxygen bond of the monomer. Copyright © 2004 Society of Chemical Industry
Stabilization of water/n‐hexane emulsions by amphiphilic copolymers based on vinyl ethers and their polycomplexes with poly(acrylic acid)
Authors: Mun Grigoriy A. , Khutoryanskiy Vitaliy V. , Nurkeeva Zauresh S. , Urkimbaeva Perizat I. , Zhunuspaev Daulet
Published: May 2004

Amphiphilic random copolymers based on vinyl ether of ethylene glycol and vinyl butyl ether as well as their polycomplexes with poly(acrylic acid) were studied as polymeric reagents for the stabilization of water/n‐hexane emulsions. The emulsion stability strongly depended on the content of vinyl butyl ether in the copolymers as well as their concentration in solution. The more hydrophobic copolymers stabilized emulsions more efficiently. An increase in the temperature and the addition of inorganic salts reduced the emulsion lifetime. The formation of interpolymer complexes between the copolymers and poly(acrylic acid) significantly influenced the stability of the emulsions. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 2625–2632, 2004
Nitrogen isotopomer site preference of N2O produced by Nitrosomonas europaea and Methylococcus capsulatus Bath
Authors: Sutka R. L. , Ostrom N. E. , Ostrom P. H. , Gandhi H. , Breznak J. A.
Published: May 2004

The original article to which this Erratum refers was published in Rapid Communications in Mass Spectrometry 17 (7) 2003, 738–745.
Semi‐global stabilization of linear systems subject to non‐right invertible constraints
Authors: Saberi Ali , Stoorvogel Anton A. , Shi Guoyong , Sannuti Peddapullaiah
Published: May 2004

Much progress has been made for the stabilization of linear systems subject to constraints. This paper summarizes the results established along the line of constraints modeled by a constrained output. Stabilization results established earlier for right invertible constraints are reviewed. New results for non‐right invertible constraints are developed in this paper. Solvability conditions for the non‐right invertible constraints have completely different characteristics than those for right invertible constraints. Copyright © 2004 John Wiley & Sons, Ltd.
Rate and magnitude‐bounded actuators: scheduled output feedback design
Authors: Jabbari Faryar , Köse İ. Emre
Published: May 2004

We study controller synthesis for systems subject to actuator magnitude and rate saturation constraints, where each actuator has a dynamic model of order at least one. The solvability conditions are expressed as finite‐dimensional linear matrix inequalities. Disturbance attenuation in terms of the energy‐to‐peak gain from the disturbance to the controlled output is considered, though other performance measures are also possible. The results apply to the more general case of systems under actuator and state constraints. Copyright © 2004 John Wiley & Sons, Ltd.
Tailoring a New Sizing Agent via Structural Modification of Pregelled Starch Molecules Part 1: Carboxymethylation and Grafting
Authors: Mostafa Khaled M. , Morsy Mahmoud S.
Published: May 2004

Pregelled starch (PS) was subjected to acid hydrolysis using phosphoric acid to prepare pregelled starches having different molecular sizes. The degraded pregelled starches were carboxymethylated at different reaction times. The carboxymethyl derivatives were grafted with either methacrylamide (MAam) or methacrylonitrile (MAN) as vinyl monomers using ceric ammonium nitrate (CAN) as initiator. Suitability of the new graft derivatives of pregelled starch as sizing agent of cotton yarns was studied. It is shown by the data that the extent of carboxymethylation, expressed as carboxyl content, increases by increasing the extent of hydrolysis and reaction time. Furthermore, the graft yield, expressed as mmol MAam or MAN monomer/100 g graft copolymer (grafted carboxymethylated pregelled starch or grafted carboxymethylated hydrolyzed pregelled starch) increases with increasing extent of carboxymethylation and degree of hydrolysis and follows the order: MAam > MAN. In addition cotton yarns sized with grafted carboxymethylated hydrolyzed pregelled starch – irrespective of the grafting monomer used – have better mechanical properties (tensile strength, elongation at break, and abrasion resistance) than hydrolyzed pregelled starches, carboxymethylated pregelled starch and carboxymethylated hydrolyzed pregelled starches.
Indigestible Starch of P. lunatus Obtained by Pyroconversion: Changes in Physicochemical Properties
Authors: Orozco‐Martínez Tonatiuh , Betancur‐Ancona David
Published: May 2004

Lima bean (Phaseolus lunatus) starch was modified using pyroconversion to produce non‐digestible starch and the functional properties of the pyrodextrinized starches were evaluated. Reaction conditions included: starch/2.2 M HCl ratio (80:1 and 160:1, w/v); temperature (90°C and 110°C) and reaction time (1 and 3 h). “In vitro” indigestible starch and color difference (ΔE) were determined and used as response variables. The optimum product was recovered from native starch treated with a 160:1 starch/HCl ratio, at 90°C for 1 h, which produced modified starches containing 49.5% indigestible starch and ΔE of 18.86. Starch pyrodextrinization decreased the amount of enzymatically available starch through formation of atypical glycosidic bonds that are not digested by the amylases and maltooligosaccharidases in the small intestine of humans. Compared to the P. lunatus native starch, the pyrodextrinized starch exhibited increased paste and gel clarity (52.7%T), solubility (88.7%), and swelling power (26 g water/g starch), a higher gelatinization temperature range (72.5–89.8°C) and lower viscosity. This process can be considered a promising treatment for production of resistant starch (RS) from P. lunatus.
Newton for ladies: gentility, gender and radical culture
Authors: MAZZOTTI MASSIMO
Published: May 2004

Francesco Algarotti's Newtonianism for Ladies (1737), a series of lively dialogues on optics, was a landmark in the popularization of Newtonian philosophy. In this essay I shall explore Algarotti's sociocultural world, his aims and ambitions, and the meaning he attached to his own work. In particular I shall focus on Algarotti's self-promotional strategies, his deployment of gendered images and his use of popular philosophy within the broader cultural and experimental campaign for the success of Newtonianism. Finally, I shall suggest a radical reading of the dialogues, reconstructing the process that brought them to their religious condemnation. What did Newtonianism mean to Algarotti? In opposition to mainstream apologetic interpretations, he seems to have framed the new experimental methodology in a sensationalistic epistemology derived mainly from Locke, pointing at a series of subversive religious and political implications. Due to the intervention of religious authorities Algarotti's radical Newtonianism became gradually less visible in subsequent editions and translations. It is only through the study of the first – clandestine – edition of the dialogues that one can begin reconstructing the meaning of Algarotti's experiments (real and fictional) and his cultural battle for a regenerated Europe.
VA practice patterns and practice guidelines for treating posttraumatic stress disorder
Authors: Rosen Craig S. , Chow Helen C. , Finney John F. , Greenbaum Mark A. , Moos Rudolf H. , Sheikh Javaid I. , Yesavage Jerome A.
Published: May 2004

Little is known about how recent ISTSS practice guidelines (E. B. Foa, T. M. Keane, & M. J. Friedman, 2000) compare with prevailing PTSD treatment practices for veterans. Prior to guideline dissemination, clinicians in 6 VA medical centers were surveyed in 1999 (n = 321) and in 2001 (n = 271) regarding their use of various assessment and treatment procedures. Practices most consistent with guideline recommendations included psychoeducation, coping skills training, attention to trust issues, depression and substance use screening, and prescribing of SSRIs, anticonvulsants, and trazodone. PTSD and trauma assessment, anger management, and sleep hygiene practices were provided less consistently. Exposure therapy was rarely used. Additional research is needed on training, clinical resources, and organizational factors that may influence VA implementation of guideline recommendations.
Seasonal and solar cycle dynamics of the auroral kilometric radiation source region
Authors: Green James L. , Boardsen Scott , Garcia Leonard , Fung Shing F. , Reinisch B. W.
Published: May 2004

Several year's worth of observations from the plasma wave instruments on both Magnetopause‐to‐Aurora Global Exploration (IMAGE) and Polar spacecraft are used to study the seasonal and solar cycle variations in the spectrum of auroral kilometric radiation (AKR). Only AKR observations when the spacecraft were in the Northern Hemisphere emission cones were used. The results from the seasonal analysis show significant changes in the AKR spectrum as a function of dipole tilt. The average AKR spectral peak for positive dipole tilt is ∼150 kHz but is ∼300 kHz during times of negative dipole tilt. In addition, the average emission spectrum for positive tilt is up to two orders of magnitude weaker over the 200–500 kHz frequency range when compared with the average emission spectrum for negative tilt. Assuming the cyclotron maser mechanism for AKR, these results imply that the AKR source region (the auroral density cavity) moves to higher altitudes during the summer and to lower altitudes during the winter. Using data from the DE‐1 plasma wave instrument, the magnetic local time of average AKR source region is also investigated with dipole tilt. From these observations it is found that for negative dipole tilt a broad AKR source region exists, ranging from ∼18 to ∼24 MLT, with peak emission coming from ∼20 MLT. In comparison, under positive dipole tilt the source region narrows (∼20 to ∼24 MLT) with peak emission at ∼22 MLT. Taking into account the above seasonal effect, a comparison of the average spectra from IMAGE and Polar plasma wave data also demonstrates a solar cycle effect. The average AKR spectrum at solar maximum has the same structure with dipole tilt as at solar minimum but is typically lower (by as much as 1–2 orders of magnitude). The observations presented support the concept that the expected increases in ionospheric densities (with positive dipole tilt for the Northern Hemisphere and solar EUV flux increases during solar maximum) play a significant role in magnetospheric‐ionospheric coupling by: (1) shortening the altitude range of the auroral plasma cavity, (2) confining the cavity to a smaller range of MLT and closer to midnight, and (3) decreasing the overall intensity of AKR by lessening the density depth of the auroral density cavity. The results of this study should be taken into account in future studies of using AKR as a substorm index and other statistical emission cone studies at both low and high frequencies.
Influence of Rossby waves on nutrient dynamics and the plankton community structure in the North Pacific subtropical gyre
Authors: Sakamoto Carole M. , Karl David M. , Jannasch Hans W. , Bidigare Robert R. , Letelier Ricardo M. , Walz Peter M. , Ryan John P. , Polito Paulo S. , Johnson Kenneth S.
Published: May 2004

Nitrate concentrations, chlorophyll a (Chl a) fluorescence, radiance, salinity, and temperature were measured on the Hawaii Air‐Sea Logging Experiment, A Long‐Term Oligotrophic Habitat Assessment (HALE ALOHA) mooring located near the Hawaii Ocean Time‐Series (HOT) Program's Station ALOHA (22°45′N; 158°W). Nitrate concentrations were determined with OsmoAnalyzers deployed at depths of 120 and 180 m. Deployments in 1997 and 1999 captured monthlong events that brought relatively cold high‐nitrate seawater up into the euphotic zone. These events were correlated with negative sea surface height (SSH) anomalies measured by the TOPEX/Poseidon satellite altimeter. These nutrient injections at the Hawaii site were predominantly associated with first baroclinic mode Rossby waves. Elevated nitrate concentrations resulted in increased Chl a concentrations, increased primary productivity, and shifts in the phytoplankton community structure, as determined by HPLC analysis of pigment concentrations. The relative increase in pigments associated with phytoplankton that can grow rapidly and exploit nitrate (e.g., haptophytes and pelagophytes) coincided with the passage of Rossby waves in 1997–1999. A long‐term combination of satellite remote sensing, moored instrumentation or remote vehicles and periodic ship‐based sampling is needed to fully characterize the spatial and temporal variability due to the passage of Rossby waves and their associated biological responses.
Generation of subsurface cyclonic eddies in the southeast Baltic Sea: Observations and numerical experiments
Authors: Zhurbas Victor , Stipa Tapani , Mälkki Pentti , Paka Vadim , Golenko Nikolai , Hense Inga , Sklyarov Vladimir
Published: May 2004

Closely spaced CTD transects performed in the summertime reveal simultaneous downward/upward bendings of temperature/salinity contours in the seasonal thermocline/permanent halocline of the Stolpe Channel and the Gulf of Gdansk, which may be interpreted as geostrophically balanced cyclonic eddies in the intermediate layer. To examine processes capable of forming the observed cyclonic eddies, a numerical simulation based on the Princeton Ocean Model (POM) has been initiated. The subsurface cyclones in the Stolpe Channel were satisfactory simulated in model runs under easterly/northerly wind conditions. Their formation was shown to result from the adjustment of the high potential vorticity (PV) outflow (from the Bornholm Basin via the Stolpe Sill) to low potential vorticity environment by vortex stretching (so‐called the PV outflow hypothesis by Spall and Price [1998]). In accordance with the real wind conditions, a cyclonic eddy observed in the intermediate layer of the Gulf of Gdansk was satisfactorily reproduced in a model run with the westerly wind shutdown, which implies westward transport throughout the Stolpe Channel and thereby excludes the PV outflow hypothesis. The subsurface cyclone simulated in the Gulf of Gdansk was traced to form in the course of relaxation of the coastal downwelling baroclinic jet.
Estimating the direct radiative forcing due to haze from the 1997 forest fires in Indonesia
Authors: Davison P. S. , Roberts D. L. , Arnold R. T. , Colvile R. N.
Published: May 2004

The El Niño event of 1997–1998 caused a severe reduction of rainfall in Indonesia that promoted the spread of forest fires, leading to a pervasive haze in the region. Here we use fire coverage data from the 1997 World Fire Atlas with a review of other available data and literature to estimate the distribution of particulate emissions from August to November 1997 and the particle size and radiative properties. Our preferred estimate of the total particulate emissions is approximately 41 Tg. The emissions have been used to drive an atmospheric model to simulate the distribution of the haze and its direct radiative effect, with and without allowing for the effects of the smoke on the atmospheric evolution. Model diagnostics of the aerosol and its radiative impact are compared with measurements and output from other models. Large decreases in the incident solar flux at the surface are obtained in the region. The simulated global mean shortwave radiative forcing at the top of the atmosphere, averaged over the 4 months, is −0.32 Wm−2. The accuracy of this calculation is discussed, and the importance of the Indonesian fires in particular and of biomass burning in general is assessed.
Confluence effects in rivers: Interactions of basin scale, network geometry, and disturbance regimes
Authors: Benda Lee , Andras Kevin , Miller Daniel , Bigelow Paul
Published: May 2004

We reviewed 14 studies documenting the effects of tributaries on river morphology at 167 confluences along 730 km of river spanning seven orders of magnitude in drainage area in western United States and Canada. In both humid and semiarid environments the probability of observing significant confluence‐related changes in channel and valley morphology due to tributary influxes of sediment (e.g., changes in gradient, particle size, and terraces, etc.) increased with the size of the tributary relative to the main stem. Effects of confluences on river morphology are conditioned by basin shape and channel network patterns, and they include the nonlinear separation of geomorphically significant confluences in river networks. Other modifying factors include local network geometry and drainage density. Confluence‐related landforms (i.e., fans, bars, terraces, etc.) are predicted to be dominated by older features in headwaters and younger features downstream, a pattern driven by the frequency and magnitude of floods and punctuated sediment supply that scale with watershed size.
A linear system model of dynamic throughfall rates beneath forest canopies
Authors: Keim Richard F. , Skaugset Arne E.
Published: May 2004

This paper describes a black box, linear system model to predict time‐varying throughfall rates using only data of time‐varying rainfall and storm total throughfall. For two forest stands in the Pacific Northwest the model predicted throughfall with mean efficiency of 0.84 when calibrated individually to 48 rainstorms and mean efficiency of 0.82 when calibrated to all storms simultaneously. The median of mean hydraulic residence times of precipitation in the canopy averaged across all storms ranged from 8 to 30 min by location within the two stands (overall median 12 min). Model predictions and performance were approximately equivalent for transfer functions based on either published equations describing storage and drip or of the form of exponential or gamma distributions. The model was insensitive to characteristics of rainstorms, so that calibrated models of water transfer through canopies were similar for storms of all sizes and intensities.
Impact of Antarctic ice shelf basal melting on sea ice and deep ocean properties
Authors: Hellmer H. H.
Published: May 2004

An approximation of Antarctica's rocky and icy coastline normally forms the southern boundary in global climate models. Such a configuration neglects extensive ice shelf areas where ocean‐ice interaction initiates a net freshwater flux to the circumpolar continental shelf equal to ∼75% of the annual mean net precipitation in coastal seas. The results of a numerical model for the Southern Ocean using two contrasting configurations with and without caverns beneath major Antarctic ice shelves are compared. They show that the freshwater flux due to deep basal melting significantly stabilizes the shelf water column in front of an ice shelf as well as downstream due to advection by the coastal current. If the freshwater from the caverns is absent, sea ice is thinner, shelf waters are warmer and saltier, and the Southern Ocean deep basins are flushed by denser waters.
Nonlinear guiding center theory of perpendicular diffusion: General properties and comparison with observation
Authors: Bieber John W. , Matthaeus W. H. , Shalchi Andreas , Qin Gang
Published: May 2004

A nonlinear guiding center (NLGC) theory for diffusion of charged particles perpendicular to the mean magnetic field was recently proposed. Here, we draw attention to a number of attractive features of this theory: (1) The theory provides a natural mechanism to connect the perpendicular mean free path with the parallel mean free path. In fact, the parallel mean free path is the only particle property required to determine uniquely the perpendicular mean free path. (2) Under a broad range of conditions, the theory predicts that the perpendicular mean free path will be of order one percent or a few percent of the parallel mean free path, in agreement with numerical simulations of particle transport. (3) For conditions representative of the inner heliosphere, the theory predicts values of the perpendicular mean free path in agreement with observational determinations from Jovian electrons and from modeling Ulysses observations of Galactic protons.
A unified approach to the tedanolides: Total synthesis of (+)-13-deoxytedanolide
Authors: Smith Amos B. , Adams Christopher M. , Barbosa Stephanie A. Lodise , Degnan Andrew P.
Published: May 2004

A unified approach for the construction of the potent marine antitumor agents (+)-tedanolide (
1
) and (+)-13-deoxytedanolide (
2
) is described. Highlights of the synthetic strategy include the development of a versatile bifunctional dithiane-vinyl iodide linchpin, the unorthodox use of the Evans–Tishchenko reaction, and a late-stage high-risk stereocontrolled introduction of the C(18,19) epoxide to achieve a total synthesis of (+)-13-deoxytedanolide (
2
).
Artificially ambiguous genetic code confers growth yield advantage
Authors: Pezo V. , Metzgar D. , Hendrickson T. L. , Waas W. F. , Hazebrouck S. , Döring V. , Marlière P. , Schimmel P. , de Crécy-Lagard V.
Published: May 2004

A primitive genetic code is thought to have encoded statistical, ambiguous proteins in which more than one amino acid was inserted at a given codon. The relative vitality of organisms bearing ambiguous proteins and the kinds of pressures that forced development of the highly specific modern genetic code are unknown. Previous work demonstrated that, in the absence of selective pressure, enforced ambiguity in cells leads to death or to sequence reversion to eliminate the ambiguous phenotype. Here, we report the creation of a nonreverting strain of bacteria that produced statistical proteins. Ablating the editing activity of isoleucyl-tRNA synthetase resulted in an ambiguous code in which, through supplementation of a limited supply of isoleucine with an alternative amino acid that was noncoding, the mutant generating statistical proteins was favored over the wild-type isogenic strain. Such organisms harboring statistical proteins could have had an enhanced adaptive capacity and could have played an important role in the early development of living systems.
Urban and Regional High Technologies: The Case of Oulu
Authors: Donnelly Tom , Hyry Martti
Published: May 2004

This paper investigates the reasons behind what has been termed the ‘Oulu Phenomenon‘ in Northern Finland. Over the past two to three decades the city of Oulu has transformed its economy from dependency on timber, paper and pulp industries into one based on High Technology, notably, telecommunications, biotechnology, electronics, multimedia and environmental technologies. In particular the paper will explore the role played by the national government via regional policy, higher education and the subsequent interaction between these, the local authorities and entrepreneurs
Evaluating the Economic Benefits from Tourism Spending through Input-Output Frameworks: Issues and Cases
Authors: Jones Calvin , Munday Max
Published: May 2004

The paper examines the economic effects of tourism spending within the framework of a regional Input-Output table augmented with a tourism satellite account. Two case studies from the Welsh economy illustrate the use of Input-Output tables to analyse the effects of tourism spending. The cases examined are the 2000 Brecon Jazz Festival, and the 1999 Rugby World Cup. In each case the effects of tourism spending are analysed in the context of varying regional economic conditions and constraints. Conclusions highlight the value of tourism satellite accounts as an aid to economic and policy planning at a time when tourism-led initiatives gain importance in regional economic development strategies.