bluuebunny/crossref_metadata_2025 huggingface dataset:
Performance of several Cr and Yb analytical techniques applied to samples of different biological origin (digesta or faeces)
Authors: Vicente Fernando , Sarraseca Armando , de Vega Antonio , Guada José A
Published: August 2004

This paper compares the performance, in terms of Cr (liquid phase marker) and Yb (solid phase marker) recovery from spiked samples, of five mineralization procedures applied to faeces, whole duodenal digesta, particulate and liquid phases of duodenal digesta, whole ruminal digesta and ruminal fluid from cattle. Two Holstein–Friesian heifers, fitted with permanent ruminal and duodenal cannulae, and fed twice daily on barley straw and a concentrate (15:85), were used as sample donors. Cr and Yb were added to the samples at 5, 25, 125 and 625 µg g−1 dry matter, and analyzed by atomic absorption spectrometry. There were differences in marker recovery (p = 0.0481) depending on the mineralization procedure utilized but their performance was not affected by marker type (p = 0.6143). The interaction between type of sample and digestion procedure was statistically significant (p = 0.0290) and the results showed that homogeneous samples (whole duodenal digesta, the particulate phase of duodenal digesta and faeces) allowed the more even distribution of the marker and an easier and more complete mineralization. In contrast, heterogeneous samples (whole rumen digesta and rumen fluid) resulted in either a lesser attachment of markers to the particles and/or incomplete mineralization of the samples, which resulted in a higher variability between procedures. The interaction between type of sample and marker was also significant (p = 0.0426), with Cr recovery being more affected by type of sample than Yb. Copyright © 2004 Society of Chemical Industry
Effects of enzymes in diets with varying energy levels on growth and egg production performance of Japanese quail
Authors: Elangovan Arumbackam V , Mandal Asit B , Tyagi Pramod K , Tyagi Praveen K , Toppo Saroj , Johri Tripurari S
Published: August 2004

The present study was conducted to evaluate the effect of feed‐grade enzyme supplementation in diets with varying levels of energy on the performance of growing and laying Japanese quails. Day‐old Japanese quails, 504 in number, were subjected to six dietary treatments with six replicates at each treatment. Each replicate had 14 chicks. The dietary treatments consisted of three energy levels ie 12.15 MJ (2900 kcal), 11.30 MJ (2700 kcal) and 10.48 MJ (2500 kcal) ME kg−1 diet and two enzyme levels (0 and 0.5 g kg−1 diet). A metabolism trial was conducted at the fourth week of age. At the end of week 5, 10 quails (five of each sex) per treatment were sacrificed for carcass characteristics and 20 female quails from each of the six dietary groups were housed in individual laying cages and fed respective layer diet to study the laying performance and egg quality up to 20 weeks of age. Body weight gains of quails fed 12.15 MJ or 11.30 MJ ME kg−1 diets were significantly higher (p < 0.01) than those fed diets with 10.46 MJ ME kg−1 diet. Feed intake was significantly lower (p < 0.01) in birds that received diet with 12.15 MJ ME kg−1 than in birds that diets containing either 11.30 or 10.46 MJ ME kg−1 diet. Feed conversion ratio (p < 0.01) was best at 12.15, followed by 11.30 and 10.46 MJ ME kg−1 diet. Enzyme supplementation did not improve the growth performance, feed intake or feed conversion efficiency of quails. Enzyme addition also did not influence nitrogen retention or energy or dry matter metabolizability. The carcass characteristics did not differ because of energy or enzyme supplementation. Feed intake increased significantly (p < 0.01) as the dietary energy level decreased. The egg production and quality characteristics remained almost similar in all the dietary treatments. It was concluded that the optimum dietary energy level for quail was 12.15 MJ (2900 kcal) ME kg−1 during the growing phase and 11.30 MJ (2700 kcal) ME kg−1 during the laying phase. Addition of feed enzymes to conventional diets containing varying levels of maize, soyabean meal, fish meal and deoiled rice bran was not beneficial to improve growth, carcass traits, egg production performance or nutrient utilization. Copyright © 2004 Society of Chemical Industry
Iberian ham headspace: odorants of intermuscular fat and differences with lean
Authors: Carrapiso Ana I , García Carmen
Published: August 2004

The odorants from the intermuscular fat of Iberian ham were characterised for the first time and compared with those of the lean. A headspace extraction method and gas chromatography–olfactometry based on the detection frequency method were used. Compounds contributing to intermuscular fat odour were aldehydes (9), ketones (3), esters (2), nitrogen‐containing compounds (2), and one alcohol (1‐octen‐3‐ol). Eight odorants were identified for the first time as constituents of dry‐cured ham fat. The most potent odorants were hexanal and (Z)‐3‐hexenal, 3‐methylbutanal, 1‐octen‐3‐one and 1‐octen‐3‐ol and 2‐methylpropanal. Significant differences with odorants from the lean of the same hams were found; the largest differences appeared in sulfur‐containing compounds (specifically hydrogen sulfide, methanethiol and 2‐methyl‐3‐furanthiol), which seem not to contribute to fat odour but are some of the most potent odorants of lean. Significant and large differences were also found for other compounds such as 1‐octen‐3‐one and 1‐octen‐3‐ol, ethyl 2‐methylpropanoate, 2‐pentanone and 2,3‐butanedione. Copyright © 2004 Society of Chemical Industry
A rapid purification procedure for cathepsin L from bovine species and production of specific antibodies
Authors: Sentandreu Miguel A , Aubry Laurent , Ouali Ahmed
Published: August 2004

Two approaches have been carried out for the production of polyclonal antibodies specific of bovine cathepsin L (EC 3.4.22.15). The first one consisted in the purification of cathepsin L from bovine liver, through the development of an original protocol that can be achieved in 4 days, and further injection in rabbits. The purification scheme included the preparation of an enriched lysosomal extract, selective precipitation with ammonium sulfate and different chromatographic steps including size‐exclusion chromatography, cation‐ and anion‐exchange chromatography and the use of an affinity column for the removal of trace amounts of bovine serum albumin. The final enzyme preparation was purified 8400‐fold and consisted predominantly in the double‐chain form of cathepsin L. This was proved by the presence of a main protein band with Mr of 25 kDa, corresponding to the cathepsin L heavy chain, in SDS‐PAGE under reducing and denaturant conditions, and was further confirmed by immunoblotting. The second approach consisted in the generation of polyclonal antibodies against the peptide sequence 99PECSAANDTGFVDIPQR115, specific of the bovine cathepsin L heavy chain. Both types of antibodies were proved to specifically recognize cathepsin L. However, while antibodies raised against the whole protein recognized native cathepsin L, the antipeptide was able to recognize the enzyme in its denatured form. Both of them are adequate for the future development of immunoassays, allowing a rapid and accurate quantification of cathepsin L levels directly in crude extracts of meat and meat‐derived products. Copyright © 2004 Society of Chemical Industry
Characterisation and variation of antioxidant micronutrients in lettuce (Lactuca sativa folium)
Authors: Nicolle Catherine , Carnat Andrée , Fraisse Didier , Lamaison Jean‐Louis , Rock Edmond , Michel Hervé , Amouroux Pierre , Remesy Christian
Published: August 2004

The main phenolic compound in six studied lettuce cultivars (five green and one red) was identified as dicaffeoyl tartaric acid. Quantitative but not qualitative differences were found in the phenolic profiles among green cultivars. The red oak leaf cultivar contained twofold more dicaffeoyl tartaric acid and 10‐fold more chlorogenic acid than the green cultivars. Total phenolics ranged from 8.4 to 12.9 mg g−1 dry weight in green varieties and reached 27.8 mg g−1 dry weight in red oak leaf. Carotenoids and vitamins E and C were also quantified. Lutein was the main carotenoid found in all cultivars, together with another xanthophyll. The period of harvesting had only a marginal influence on total phenolic levels, whereas carotenoid and vitamin E levels were higher at the second period of harvesting. Vitamin C levels ranged between 6.1 and 9.9 mg per 100 g fresh weight. We investigated the total antioxidant power in lettuce. Total phenolics accounted for more than 60% of the total antioxidant capacity. Dicaffeoyl tartaric acid accounted for 55%. Copyright © 2004 Society of Chemical Industry
Textural changes during cooking of cassava (Manihot esculenta Crantz) roots
Authors: Beleia Adelaide , Yamashita Fabio , de Moraes Sandra R , da Silveira César A , Miranda Lílian A
Published: August 2004

Consumer acceptability of cassava food products depends mostly on the final texture of the cooked tissue. The age of the roots at harvest seems to be an important factor in determining the final texture. Two cassava cultivars harvested at 8, 17 and 30 months after planting were used for texture loss determination by a puncture test after cooking at constant boiling water temperature. Kinetic data were analysed using fractional conversion. The raw tissue showed decreasing or constant peak yield force values as the root aged. There was a gradual first‐order softening during cooking, with decreasing rate constant as the root aged. Copyright © 2004 Society of Chemical Industry
Highly precise pulsed selective laser sintering of metallic powders
Authors: Fischer P , Romano V , Blatter A , Weber H P
Published: August 2004

We studied the influence of the laser parameters on the
material properties of selectively laser sintered Titanium and
Platinum-alloyed powders, which are both of paramount interest in
modern technology. In this article, we show that with an
appropriate energy deposition in the metallic powder layer, the
material properties of the selectively laser sintered parts can
locally be tailored to the requirements of the finished work
piece. By adapting the laser parameters of a Q-switched Nd:YAG
laser, notably pulse duration and local intensity, the degree of
porosity, density and even the crystalline microstructure can be
controlled. Pulsed interaction allows in addition to minimize the
average power needed for consolidation of the metallic powder, and
leads to less residual thermal stresses. With laser post
processing, the surface can achieve bulk-like density.

We also
demonstrate for the first time to our knowledge the highly precise
selective laser sintering of steel micro powder with a lateral
accuracy of less than 10 micrometers by using a modelocked Nd:YAG
laser. Furthermore, we present the possibility of forming metallic
glass components by sintering amorphous metallic powders.
Computer modeling of optical properties of gold ellipsoidal
nanoparticles at laser radiation wavelengths
Authors: Pustovalov V K , Babenko V A
Published: August 2004

Processes of laser interaction with metal (gold)
nanoparticles are of great interest for laser applications in
nanotechnology, engineering, and medicine. Optical properties of
nanoparticles determine photophysical and photochemical processes
during laser treatment. Computer calculation of efficiency factors
of absorption, scattering and extinction of radiation by
ellipsoidal gold nanoparticles (two-dimensional ellipsoids of
revolution) with small semiaxes in the range 5–100 nm, for some
values of aspect ratio and angle of orientation of ellipsoid with
respect to direction of laser radiation propagation and for some
laser wavelengths is performed. The estimation of absorbed and
scattered laser radiation energy by gold ellipsoidal
nanoparticles, their maximal temperatures and comparison with
experimental data is made.
Catalyst Systems for Alkene Polymerization Based on Metallocene Complexes and Phenoxy Alumoxane with a Perfluorinated Phenyl Group
Authors: Kissin Yury V.
Published: August 2004

Summary: This paper describes the use of pentafluorophenoxy alumoxane, an oligomeric compound containing Al(OC6F5)O units, as a cocatalyst for metallocene complexes in alkene polymerization reactions. Pentafluorophenoxy alumoxane is produced by two alternative routes. The first route consists of two consecutive reactions: (a) the reaction of AlR3 with C6F5OH, and (b) the reaction of the product of the first step with water. The second route is the reaction between methylalumoxane and C6F5OH.

The synthesis of pentafluorophenoxy alumoxane oligomers.

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The synthesis of pentafluorophenoxy alumoxane oligomers.
A Novel, Facile Method for the Preparation of Uniform, Reactive Maleic Anhydride/Vinyl Acetate Copolymer Micro‐ and Nanospheres
Authors: Xing Chang‐Min , Yang Wan‐Tai
Published: August 2004

Summary: A novel, stabilizer‐free dispersion polymerization with alkyl esters as reaction media gives uniform alternating microspheres of maleic anhydride (MAn)/vinyl acetate (VAc) copolymer. The diameter of the copolymer microspheres could be precisely controlled from 80 to 750 nm by changing the monomer concentration or feed ratio. Moreover, this new type of copolymer microspheres with reactive anhydride groups on the surface has good solubility in common nontoxic solvents such as water and ethanol.

SEM image of the powder surface of copolymer microspheres formed at [MAn] = [VAc] = 1.5 M.

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SEM image of the powder surface of copolymer microspheres formed at [MAn] = [VAc] = 1.5 M.
A Self‐Assembly Approach to Temperature‐Responsive Polymer Nanocontainers
Authors: Chen Xiangrong , Ding Xiaobin , Zheng Zhaohui , Peng Yuxing
Published: August 2004

Summary: Thermosensitive polymer nanocontainers were formed by self‐assembly of diblock copolymers poly(2‐cinnamoylethyl methacrylate)‐block‐poly(N‐isopropylacrylamide) (PCEMA‐block‐PNIPAM) and subsequent photo‐crosslinking of the PCEMA shells. It was found that the diameter of the nanocontainers ranges from tens of nanometers to thousands of nanometers, depending on the self‐assembly conditions. The phase transition of the nanocontainers takes place at 32 °C; the structural changes are reversible in a heating and cooling cycle.

Schematic illustration of the structural transition behavior of the thermosensitive polymer nanocontainers.

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Schematic illustration of the structural transition behavior of the thermosensitive polymer nanocontainers.
Deep Quenching: A Special Method to Study Stress‐Induced Crystallization and Control the Lamellar Growth Direction
Authors: Xu Jun , Guo Bao‐Hua , Zhang Zeng‐Min , Wu Qiong , Chen Guo‐Qiang
Published: August 2004

Summary: Liquid‐nitrogen quenching was applied to study the enthalpy effect on the stress‐induced crystallization of microbial polyesters. Crystallization bands of poly(3‐hydroxybutyrate) exhibited the potential to reveal the stress distribution in the melt; while crystallization of poly[(3‐hydroxybutyrate)‐co‐(3‐hydroxyhexanoate)] gave shish‐kebab structures. Polarized‐light micrographs confirmed that the enhanced nucleation was attributed to the tensile stress. Furthermore, control of the quenching direction provides a method to direct the lamellar growth.

Polarized‐light micrographs of PHB film crystallized at 90 °C after quenching in liquid nitrogen from the melt. The normal of the bands, namely the lamellar growth direction, runs predominantly parallel to the stress direction.

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Polarized‐light micrographs of PHB film crystallized at 90 °C after quenching in liquid nitrogen from the melt. The normal of the bands, namely the lamellar growth direction, runs predominantly parallel to the stress direction.
Suppression of inducible nitric oxide synthase and cyclooxygenase‐2 in downregulating nuclear factor‐kappa B pathway by Garcinol
Authors: Liao Chiung‐Ho , Sang Shengmin , Liang Yu‐Chih , Ho Chi‐Tang , Lin Jen‐Kun
Published: August 2004

Garcinol is a polyisoprenylated benzophenone derivative of Garcinia indica fruit rind and other species. Recent studies have demonstrated that garcinol exhibited antioxidative effects in vitro. In this study, we found that garcinol inhibited the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase‐2 (COX‐2) in lipopolysaccharide (LPS)‐activated macrophages. Western blot analyzes and gel‐shift assays revealed that garcinol strongly blocks the activation of eukaryotic transcription factor nuclear factor‐kappa B (NF‐κB)‐induced by LPS. Moreover, transient transfection experiments showed that garcinol inhibited the NF‐κB‐dependent transcriptional activity. Based on these data, we demonstrated that inhibition of LPS‐induced NF‐κB activation occurred through suppressing the phosphorylation of IκBα and p38 mitogen‐activated kinase (MAPK). Garcinol also lowers the LPS‐induced increase of intracellular reactive oxygen species (ROS), which contributes to the activation of NF‐κB. The NF‐κB signaling pathway leads to inflammatory reaction and our results suggest that garcinol suppresses the expression of iNOS in this pathway. © 2004 Wiley‐Liss, Inc.
Waypoint analysis for command and control
Authors: Wendt David A. , Irwin Mark E. , Cressie Noel
Published: August 2004

Command and Control (C2) in a military setting can be epitomized in battles‐of‐old when commanders would seek high ground to gain superior spatial‐temporal information; from this vantage point, decisions were made and relayed to units in the field. Although the fundamentals remain, technology has changed the practice of C2; for example, enemy units may be observed remotely, with instruments of varying positional accuracy. A basic problem in C2 is the ability to track an enemy object in the battlespace and to forecast its future position; the (extended) Kalman filter provides a straightforward solution. The problem changes fundamentally if one assumes that the moving object is headed for an (unknown) location, or waypoint. This article is concerned with the new problem of estimation of such a waypoint, for which we use Bayesian statistical prediction. The computational burden is greater than an ad hoc regression‐based estimate, which we also develop, but the Bayesian approach has a big advantage in that it yields both a predictor and a measure of its variability. © 2004 Wiley Periodicals, Inc. Naval Research Logistics, 2004
Modelling heat transfer in two‐fluid interfacial flows
Authors: Mehdi‐Nejad V. , Mostaghimi J. , Chandra S.
Published: August 2004

This paper presents a method to calculate heat transfer across an interface separating immiscible fluids. A volume tracking method was used to model the simultaneous movement of mass, momentum and energy across cell boundaries. Both first‐ and second‐order methods were used to approximate temperature fields with sharp gradients that exist near the fluid–fluid interface. Temperature distributions around hot droplets surrounded by a colder fluid with uniform velocity were calculated and the magnitude of false diffusion identified. The effect of changing the thermal diffusivity of the surrounding fluid was studied. It was found that in most cases a second‐order approximation, such as the van Leer scheme, is sufficient for estimating advection temperatures. To demonstrate the capabilities of the model we modelled molten tin droplets falling in an oil bath. The development of vortices behind droplets was modelled and the effect of fluid re‐circulation and oil thermal conductivity on heat dissipation studied. Copyright © 2004 John Wiley & Sons, Ltd.
Algorithms for the analysis of 3D finite strain contact problems
Authors: Areias P. M. A. , César de Sá J. M. A. , Conceição António C. A.
Published: August 2004

From the constraint imposition aspects in 3D to friction regularization, various ideas are exposed in this paper. A variation of the Rockafellar Lagrangian is proposed which results in continuous second‐order derivatives if Lagrange multiplier estimates are greater or equal than one. This fact allows the adoption of a full second‐order (i.e. Lagrange–Newton) method avoiding sequential unconstrained minimization techniques. An algorithm for global and local contact detection is presented which is developed for dealing with large step sizes typical of implicit methods. A modified constraint definition to deal with non‐smooth situations is presented. Aspects of friction implementation, including a regularization scheme which ensures stepwise objectivity, are detailed. Finally, several illustrative examples are carried out with success. Copyright © 2004 John Wiley & Sons, Ltd.
Welfare transitions in the 1990s: The economy, welfare policy, and the EITC
Authors: Grogger Jeffrey
Published: August 2004

The rapid decline in the welfare caseload remains a subject of keen interest to both policymakers and researchers. In this paper, I use data from the Survey of Income and Program Participation spanning the period from 1986 to 1999 to analyze how the economy, welfare reform, the earned income tax credit (EITC), and other factors influence welfare entries and exits, which in turn affect the caseload. I find that the decline in the welfare caseload resulted from both increases in exits and decreases in entries. Entries were most significantly affected by the economy, the decline in the real value of welfare benefits, and the expansion of the EITC. Exits were most significantly affected by the economy and federal welfare reform. Federal reform had its greatest effects on longer‐term spells of the type generally experienced by more disadvantaged recipients. Some out‐of‐sample predictions help explain the otherwise puzzling observation that, despite substantial increases in the unemployment rate since 2000, caseloads have remained roughly constant. © 2004 by the Association for Public Policy Analysis and Management
Adolescents' formal employment and school enrollment: Effects of state welfare policies
Authors: Hao Lingxin , Astone Nan M. , Cherlin Andrew J.
Published: August 2004

Variations in state welfare policies in the reform era may affect adolescents through two mechanisms: A competing labor market hypothesis posits that stringent state welfare policies may reduce adolescent employment; and a signaling hypothesis posits that stringent welfare policies may promote enrollment. To test these hypotheses, we use a dynamic joint model of adolescents' school enrollment and formal employment, separating state welfare policies from non‐welfare state policies, state labor market conditions, and unobserved state characteristics. Longitudinal data from the NLSY97 on adolescents aged 14 to 18 and various state data sources over the period 1994–1999 support the competing labor market effect but not the signaling effect. In particular, lower‐income dropouts suffer more severely from fewer labor market opportunities when state welfare policies are more stringent, which indicates that welfare reform may compromise work opportunities for lower‐income dropouts. © 2004 by the Association for Public Policy Analysis and Management.
Can child care assistance in welfare and employment programs support the employment of low‐income families?
Authors: Gennetian Lisa A. , Crosby Danielle A. , Huston Aletha C. , Lowe Edward D.
Published: August 2004

Policymakers have long recognized child care as a key ingredient in low‐income parents' employability. We examine the effects of expansions in child care policies that were bundled with a mix of employment‐related policies and implemented as part of several random assignment studies on families' child care access and cost. Almost all of these welfare and employment programs increased employment and led to concomitant increases in the use of child care, especially paid child care. Only the programs that also expanded access or affordability of child care consistently increased the use of child care subsidies and reduced out‐of‐pocket costs to parents, allowing parents to purchase center‐based care. With one exception, such programs had small effects on employment‐related child care problems, suggesting that broader and more generous targeting of child care assistance may be important for achieving the goal of enhancing the stability of employment among low‐income families. © 2004 by the Association for Public Policy Analysis and Management.
A “third way” in welfare reform? Evidence from the United Kingdom
Authors: Hills John , Waldfogel Jane
Published: August 2004

U.S. welfare reforms, whether promoting work first or human capital development, have had in common an emphasis on employment as the key to improving the life chances of children living in single‐mother families. We describe in this article a different type of reform—a “third way” in welfare reform. The welfare reforms carried out in the United Kingdom since the “New Labour” government of Tony Blair was elected in 1997 have included promotion of paid work, but alongside two other components—an explicit commitment to reduce and eventually eliminate child poverty, and a campaign against long‐term disadvantage under the label of tackling “social exclusion.” Welfare‐to‐work reforms promoting employment for single mothers have been active but not as punitive as in the United States. At the same time, the tax credit and cash benefit system has been radically overhauled, benefiting low‐income families with children, whether or not parents are working. Early indications suggest a more rapid fall in child poverty in the United Kingdom since its reforms began than in the United States since its reforms, and a faster rise in single‐mother employment. © 2004 by the Association for Public Policy Analysis and Management.
“Just give me a number!” Practical values for the social discount rate
Authors: Moore Mark A. , Boardman Anthony E. , Vining Aidan R. , Weimer David L. , Greenberg David H.
Published: August 2004

A major reason the quality of cost‐benefit analysis (CBA) varies widely is inconsistent use of the social discount rate (SDR). This article offers guidance about the choice of the SDR. Namely, we recommend the following procedures: If the project is intragenerational (does not have effects beyond 50 years) and there is no crowding out of private investment, then discount all flows at 3.5 percent; if the project is intragenerational and there is some crowding out of investment, then weight investment flows by the shadow price of capital of 1.1 and then discount at 3.5 percent; if the project is intergenerational and there is no crowding out of investment, then use a time‐declining scale of discount rates; if the project is intergenerational and investment is crowded out, then convert investment flows during the first 50 years to consumption equivalents using a shadow price of 1.1, and then discount all of these flows at 3.5 percent, and discount all flows after the 50th year using time‐declining rates. We then compare current discounting practices of U.S. federal agencies with our estimates. Consistent use of the recommended rates would eliminate arbitrary choices of discount rates and would lead to better public sector decision‐making. © 2004 by the Association for Public Policy Analysis and Management.
Heavy alcohol use and youth suicide: Evidence from tougher drunk driving laws
Authors: Carpenter Christopher
Published: August 2004

This paper uses the widespread variation across states in the timing of adoption of tougher drunk driving laws that set very low legal blood alcohol limits for drivers under age 21—“zero tolerance” (ZT) laws—to provide new evidence on the causal effect of alcohol use on youth suicide. ZT laws reduced heavy episodic drinking by underage men, with no effect for slightly older males. I estimate the reduced form effect of ZT policy adoption on suicide deaths among 15–17‐, 18–20‐, 21–24‐, and 25–29‐year‐old males and females for the period 1981–1998. The models control for macroeconomic conditions, demographic changes, other alcohol control policies, state and year fixed effects, and smooth state trends. Results indicate statistically significant reductions in suicide among young males aged 15–17 and 18–20 associated with adoption of ZT laws on the order of 7 to 10 percent. I find no effects for slightly older males who were unaffected by the tougher drunk driving laws, and no consistent effects for females. These results provide new and compelling evidence that heavy alcohol use causes young male suicide. © 2004 by the Association for Public Policy Analysis and Management.
Are Colombian sickness funds cream skimming enrollees? An analysis with suggestions for policy improvement
Authors: Trujillo Antonio J. , McCalla Dawn C.
Published: August 2004

One of the primary objectives of Colombian social health insurance reform was to increase competition among for‐profit insurers. Unfortunately, the flat capitated formula creates an opportunity for sickness funds to maximize reimbursement gains by “cream skimming”—selecting against unhealthy individuals. This paper explores sickness fund selection behavior to evaluate the efficiency losses associated with the introduction of managed competition in Colombia. Data from a 1997 Colombian household survey are analyzed with a bivariate probit model with partial observability using instrumental variables. The model yields some evidence of sickness fund selection based on health status. Public policy options to discourage risk selection by health status are discussed. © 2004 by the Association for Public Policy Analysis and Management.
Congenital cervical neuroblastoma
Authors: Cardesa‐Salzmann Teresa M. , Mora‐Graupera Jaume , Claret Gemma , Agut Thais
Published: August 2004

Primary congenital cervical neuroblastomas are very rare. A history of upper aerodigestive compromise with Horner syndrome can be of value for the early diagnosis of this lesion. Congenital neuroblastomas usually have a favorable outcome. Like all the other clinically relevant groups of neuroblastomas, management should take into consideration the biological findings of each tumor, which predicts outcome than other clinical findings. Pediatr Blood Cancer 2004;43:785–787. © 2004 Wiley‐Liss, Inc.
Aromaticity and stability of furofurans and thienothiophenes
Authors: Aihara Jun‐ichi
Published: August 2004

The topological resonance energy (TRE) calculated for a polycyclic π‐system cannot always be used to predict the thermodynamic or kinetic stability of the π‐system. For example, furo[3,4‐c]furan (1d) and thieno[3,4‐c]thiophene (2d) are aromatic with large positive TREs and large negative nucleus independent chemical shift (NICS) values at the ring centers. However, these heterobicycles are predicted to be very high in energy with very small HOMO–LUMO energy separations. These unusual properties of the heterobicycles are closely associated with the fact that classical resonance structures cannot be drawn for them. In general, the kinetic stability of a polycyclic π‐system reflects not only the aromaticity of the π‐system but also the kinetic stability of the polyene reference. Copyright © 2004 John Wiley & Sons, Ltd.
Solvation effects on spirooxazine to merocyanine thermal reversion kinetics in acetonitrile–water binary mixtures
Authors: Gaeva Elena B. , Pimienta V. , Metelitsa A. V. , Voloshin N. A. , Minkin V. I. , Micheau J. C.
Published: August 2004

In solution, the photochromic molecule 5‐methoxyspiro[indole‐phenanthrolinoxazine] (SPO) is in equilibrium with its corresponding merocyanine open isomer. In pure acetonitrile, there is about 22.5% of the open form, whereas in acetonitrile–water binary solvents this proportion increases to more than 60% when the water molar fraction χ(H2O) is around 0.80. Irradiation in the visible range leads to a photobleached steady state in which the proportion of the merocyanine open isomer decreases significantly. When irradiation is switched off, a slow thermal reversion of the closed spirooxazine to the open merocyanine takes place until the initial equilibrium position is reached. Kinetic analysis of a whole set of relaxation curves recorded at various water contents was used to establish a model involving multiple equilibria between three merocyanines in different solvation states (solvated by acetonitrile, solvated by an acetonitrile–water complex and hydrated). Their relative proportions, which are dependent on the binary mixture composition, were determined, in addition to their corresponding visible spectra. Copyright © 2004 John Wiley & Sons, Ltd.
Resonance and field/inductive substituent effects on the gas‐phase acidities of para‐substituted phenols: a direct approach employing density functional theory
Authors: Barbour Josiah B. , Karty Joel M.
Published: August 2004

Relative gas‐phase acidities of para‐substituted phenols (1, Sub—C6H4—OH) and their ω‐substituted para‐alkylphenol analogs [2, Sub—(CH2)n—C6H4—OH] were calculated at the B3LYP/6–31+G* and AM1 levels of theory. The acidity of a substituted molecule of 2 is compared with that of the unsubstituted molecule of 2 to determine the field/inductive effect of the substituent on the acidity of 2. This field/inductive effect was extrapolated to n = 0, yielding the field/inductive effect of the substituent on the acidity of 1. The derived field/inductive effect in 1 was subtracted from the difference in acidity between 1 and phenol in order to determine the resonance effect of the substituent on the acidity of 1. Our results are compared with the field/inductive and resonance substituent parameters empirically derived from previous experimental solution studies. Copyright © 2004 John Wiley & Sons, Ltd.
Synthesis and characterization of well‐defined diblock and triblock copolymers of poly(N‐isopropylacrylamide) and poly(ethylene oxide)
Authors: Hong Chun‐Yan , You Ye‐Zi , Pan Cai‐Yuan
Published: August 2004

Well‐defined diblock and triblock copolymers composed of poly(N‐isopropylacrylamide) (PNIPAM) and poly(ethylene oxide) (PEO) were successfully synthesized through the reversible addition–fragmentation chain transfer polymerization of N‐isopropylacrylamide (NIPAM) with PEO capped with one or two dithiobenzoyl groups as a macrotransfer agent. 1H NMR, Fourier transform infrared, and gel permeation chromatography instruments were used to characterize the block copolymers obtained. The results showed that the diblock and triblock copolymers had well‐defined structures and narrow molecular weight distributions (weight‐average molecular weight/number‐average molecular weight < 1.2), and the molecular weight of the PNIPAM block in the diblock and triblock copolymers could be controlled by the initial molar ratio of NIPAM to dithiobenzoate‐terminated PEO and the NIPAM conversion. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 4873–4881, 2004
Iron halide mediated atom transfer radical polymerization of methyl methacrylate with N‐alkyl‐2‐pyridylmethanimine as the ligand
Authors: Zhang Huiqi , Schubert Ulrich S.
Published: August 2004

The controlled atom transfer radical polymerization (ATRP) of methyl methacrylate (MMA) catalyzed by iron halide/N‐(n‐hexyl)‐2‐pyridylmethanimine (NHPMI) is described. The ethyl 2‐bromoisobutyrate (EBIB)‐initiated ATRP with [MMA]0/[EBIB]0/[iron halide]0/[NHPMI]0 = 150/1/1/2 was better controlled in 2‐butanone than in p‐xylene at 90 °C. Initially added iron(III) halide improved the controllability of the reactions in terms of molecular weight control. The p‐toluenesulfonyl chloride (TsC1)‐initiated ATRP were uncontrolled with [MMA]0/[TsC1]0/[iron halide]0/[NHPMI]0 = 150/1/1/2 in 2‐butanone at 90 °C. In contrast to the EBIB‐initiated system, the initially added iron(III) halide greatly decreased the controllability of the TsC1‐initiated ATRP. The ration of iron halide to NHPMI significantly influenced the controllability of both EBIB and TsC1‐initiated ATRP systems. The ATRP with [MMA]0/[initiator]0/[iron halide]0/[NHPMI]0 = 150/1//1/2 provided polymers with PDIs ≥ 1.57, whereas those with [iron halide]0/[NHPMI]0 = 1 resulted in polymers with PDIs as low as 1.35. Moreover, polymers with PDIs of approximately 1.25 were obtained after their precipitation from acidified methanol. The high functionality of the halide end group in the obtained polymer was confirmed by both 1H NMR and a chain‐extenstion reaction. Cyclic voltammetry was utilized to explain the differing catalytic behaviors of the in situ‐formed complexes by iron halide and NHPMI with different molar ratios. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 4882–4894, 2004
Reaction control in radical polymerization of di‐n‐butyl itaconate utilizing a hydrogen‐bonding interaction
Authors: Hirano Tomohiro , Higashi Kousuke , Seno Makiko , Sato Tsuneyuki
Published: August 2004

We have reported that intramolecular chain‐transfer reaction takes place in radical polymerization of itaconates at high temperatures and/or at low monomer concentrations. In this article, radical polymerizations of di‐n‐butyl itaconate (DBI) were carried out in toluene at 60 °C in the presence of amide compounds. The 13C‐NMR spectra of the obtained poly(DBI)s indicated that the intramolecular chain‐transfer reaction was suppressed as compared with in the absence of amide compounds. The NMR analysis of DBI and N‐ethylacetamide demonstrated both 1:1 complex and 1:2 complex were formed at 60 °C through a hydrogen‐bonding interaction. The ESR analysis of radical polymerization of diisopropyl itaconate (DiPI) was conducted in addition to the NMR analysis of the obtained poly(DiPI). It was suggested that the suppression of the intramolecular chain‐transfer reaction with the hydrogen‐bonding interaction was achieved by controlling the conformation of the side chain at the penultimate monomeric unit of the propagating radical with an isotactic stereosequence. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 4895–4905, 2004
Investigation of the solid phase synthesis of tyrosine‐derived diphenol monomers with resin‐bound carbodiimide coupling reagents
Authors: Sen Gupta Anirban , Lopina Stephanie T.
Published: August 2004

Tyrosine‐derived pseudo‐polypeptides have recently been established as potential biomaterials. The bulk production of these polymers is dependant upon the convenient synthesis of tyrosine‐derived diphenolic monomers. Suitable solution phase methods for the synthesis of such monomers, with transient activated esters, have been reported previously by Kohn, J.; Langer, R. In Biomaterials Science: An Introduction to Materials in Medicine; Ratner, B. D.; Hoffman, A. S.; Schoen, F. J.; Lemons, J. E., Eds.; Academic Press: New York, 1996; pp 64–72. However, for all the methods reported by them, purification and isolation of the diphenol monomer involves rigorous extraction, column purification, or an extensive aqueous workup. These may lead to the incorporation of solvent‐based as well as inorganic impurities and also may lead to difficulties in the process scale‐up. In this article, an alternate and relatively more convenient method for the synthesis of tyrosine‐based diphenol monomers is reported. This involved the investigation of polymer resin‐bound carbodiimide in the solid‐phase synthesis of L‐tyrosine‐based diphenolic monomers. This method was found to eliminate the need for rigorous purification processes and was found to maintain reasonable yield as well as maintain purity of the final monomer product. The monomer was able to produce polymers of a reasonably high‐molecular‐weight and a narrow polydispersity. The amide bond formation by such a polymer‐tethered reagent can be described to follow a reverse‐Merrifield sense and the method is relatively convenient to scale up. The L‐tyrosine‐based diphenolic monomeric compound formed by this method was analyzed by NMR, Fourier transform infrared, and elemental microanalysis techniques for chemical structure and composition. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 4906–4915, 2004
The contact toxicity of indoxacarb and five other insecticides to Orius insidiosus (Hemiptera: Anthocoridae) and Aphidius colemani (Hymenoptera: Braconidae), beneficials used in the greenhouse industry
Authors: Bostanian Noubar J , Akalach Mohammed
Published: August 2004

The contact toxicity of indoxacarb, abamectin, endosulfan, insecticide soap, S‐kinoprene and dimethoate to Orius insidiosus (Say) and Aphidius colemani Viereck were studied in the laboratory. These beneficials are often used in the greenhouses to manage various insect pests. Indoxacarb is slow acting and therefore, to estimate lethal dosages, observations should be continued for several days until data stabilize. Seven days after treatment, the LC50 was 0.119 g AI litre−1 for O insidiosus adults and 0.019 g AI litre−1 for A colemani. At that time, the recommended field concentration was 0.479 times the LC50 for O insidiosus adults and three times the LC50 for A colemani. In contrast, indoxacarb had no adverse effect on the reproductive capacity of wasps surviving a treatment or the developing wasps in the aphid mummy. Among the other insecticides S‐kinoprene was the most innocuous while dimethoate was the most toxic to the two beneficials. The other insecticides had overlapping toxicities. Copyright © 2004 Society of Chemical Industry
Evaluation of hydrophobic and hydrophilic kaolin particle films for peach crop, arthropod and disease management
Authors: Lalancette Norman , Belding Robert D , Shearer Peter W , Frecon Jerome L , Tietjen William H
Published: August 2004

Hydrophobic and/or hydrophilic kaolin particle film treatments to peach (Prunus persica (L) Batsch) trees were evaluated for crop and pest management capabilities in six studies from 1997 to 2000. Unsprayed control and standard treatments, the latter consisting of a commercial pesticide program, were included for comparison. Treatments in initial studies were applied via handgun, which resulted in a uniform and heavy deposit of kaolin after the first application. In contrast, treatments in subsequent studies used airblast equipment, which provided a uniform but less dense coverage, even after multiple applications. Results showed that both formulations of kaolin provided control of oriental fruit moth (Grapholita molesta (Busck)), plum curculio (Conotrachelus nenuphar (Herbst)) and Japanese beetle (Popillia japonica Newman) that was comparable with or better than the standard pesticide program. Effective management of late season catfacing insects (tarnished plant bugs Lygus lineolaris (Palisot de Beauvois) and stinkbugs Acrosternum hilare (Say), Euschistus servus (Say), and E tristigmus (Say)) and leafrollers (undetermined species) was also observed, although kaolin applications significantly increased phytophagous mite (Panonychus ulmi (Koch)) levels. In contrast to arthropod management, kaolin failed to control either peach scab (Cladosporium carpophilum (Von Thümen)) or rusty spot (Podosphaera leucotricha (Ell & Ev) ES Salmon) in any of the 4 years of the study. However, hydrophobic kaolin provided effective brown rot (Monilinia fructicola (G Winter) Honey) control when applied via handgun, and partial control when applied via airblast; hydrophilic kaolin failed to provide any control. These results suggest that hydrophobicity and deposit density may be important factors for effective disease management. The application of kaolin significantly delayed fruit maturation, increased fruit size and increased soluble solids relative to the standard. This effect, attributed to a reduction in plant stress, also resulted in increased fruit number and yield on young trees, indicating that an accentuated beneficial response from kaolin applications may be possible. Copyright © 2004 Society of Chemical Industry
Modelling the interactions between phenology and insecticide resistance genes in the codling moth Cydia pomonella
Authors: Boivin Thomas , Chadœuf Joël , Bouvier Jean‐Charles , Beslay Dominique , Sauphanor Benoît
Published: August 2004

In the codling moth Cydia pomonella (L), insecticide resistance genes have been associated with pleiotropic effects affecting phenology. In this paper, we investigated whether an increase in the frequency of insecticide resistance in field populations of C pomonella was likely to entail significant divergences in the temporal occurrence of both susceptible and insecticide‐resistant individuals. For this purpose, we built a phenological model that provided suitable predictions of the distinct and diverging seasonal evolutions of populations of a susceptible and two insecticide‐resistant (at two and three loci) homozygous genotypes of C pomonella. Model simulations for each genotype were further compared with pheromone trap catches recorded in a field insecticide‐treated population over an 8‐year period (from 1992 to 2000), which reflected the progressive annual increase in the frequency of resistance in southeastern France. We found a significant delay in field adult emergence relative to those predicted by the homozygous susceptible model, and the magnitude of such a delay was positively correlated with increasing frequencies of insecticide resistance in the sampled field population of C pomonella. Adult emergence predicted in the theoretical population that was homozygous for resistance at two loci converged with those recorded in the field during the investigated 8‐year period. This suggested that the pleiotropic effects of resistance were likely to result in a significant phenological segregation of insecticide‐resistant alleles in the field. The results of this study emphasized the potential for pest populations exposed to chemical selection to evolve qualitatively with respect to phenology. This may raise critical questions regarding the use of phenological modelling as a forecasting tool for appropriate resistance management strategies that would take into account the diverging seasonal evolutions of both insecticide resistance and susceptibility. Copyright © 2004 Society of Chemical Industry
Ground and first‐excited global potential energy surfaces of the H2O+He complex: Predictions of ion mobilities
Authors: Chen Xin , Thachuk M.
Published: August 2004

Ion mobilities of H2O+ drifting in helium are calculated and compared with experiment. These calculations employ global potential energy surfaces of the H2O+–He complex, which in the present case were calculated ab initio at the unrestricted MP2 level of theory using a basis set of aug‐cc‐pVTZ quality, and treating the ion as a rigid body. Details are presented of the general characteristics of both the ground and first‐excited electronic states of the complex. Although only the ground‐state surface was used for the mobility calculations, the ab initio determination of the ground state necessitated the inclusion of the first‐excited state owing to the presence of a crossing between the two. This crossing is also described. Mobilities calculated from the global surfaces are in good agreement with experiment. © 2004 Wiley Periodicals, Inc. Int J Quantum Chem, 2005
Leveraging legacy codes to distributed problem‐solving environments: a Web services approach
Authors: Li M. , Qi M.
Published: August 2004

This paper presents WSOWG, a Web‐services‐oriented wrapper generator for automatically wrapping non‐networked legacy codes as Web services for reuse in distributed problem‐solving environments. Using WSOWG, a finite element based computational fluid dynamics (CFD) legacy code has been wrapped as a Web service. A problem‐solving environment for simulating incompressible Navier–Stokes flows has also been implemented. A user makes use of the CFD service through a Web page without knowing the exact implementation of the service. In this way, a user's computing environment can be extended to a heterogeneous distributed computing environment. Performance evaluation shows that the overhead to invoke the CFD Web service generated by WSOWG using Simple Object Access Protocol (SOAP) and CORBA Internet Inter‐ORB Protocol (IIOP) is reasonable compared with that of invoking another CFD Web service manually wrapped from the CFD legacy code using SOAP only. Copyright © 2004 John Wiley & Sons, Ltd.