bluuebunny/crossref_metadata_2025_split huggingface dataset:
Quasi‐embeddings of Steiner triple systems, or Steiner triple systems of different orders with maximum intersection
Authors: Dukes Peter , Mendelsohn Eric 
Published: November 2004

AbstractIn this paper, we present a conjecture that is a common generalization of the Doyen–Wilson Theorem and Lindner and Rosa's intersection theorem for Steiner triple systems. Givenu,v≡ 1,3 (mod 6),u<v< 2u +  1, we ask for the minimumrsuch that there exists a Steiner triple system$(U,\,{\cal B}),\,|U|=u$such that some partial system$(U,{\cal B}\,\backslash{\partial})$can be completed to an STS$(v),\,(V,\,{\cal B}{^\prime})$, where |∂| =r. In other words, in order to “quasi‐embed” an STS(u) into an STS(v), we must removerblocks from the small system, and thisris the least such with this property. One can also view the quantity (u(u− 1)/6) −ras the maximum intersection of an STS(u) and an STS(v) withu<v. We conjecture that the necessary minimumr =  (v−u) (2u +  1 −v)/6 can be achieved, except whenu =  6t +  1 andv= 6t +  3, in which case it isr =  3tfort≠ 2, orr =  7 whent =  2. Using small examples and recursion, we solve the casesv−u =  2 and 4, asymptotically solve the casesv−u =  6, 8, and 10, and further show for givenv−u> 2 that an asymptotic solution exists if solutions exist for a run of consecutive values ofu(whose required length is no more thanv−u). Some results are obtained forvclose to 2u +  1 as well. The cases where ≈ 3u/2 seem to be the hardest. © 2004 Wiley Periodicals, Inc.
Effects of cultivar, root weight, storage and boiling on carbohydrate content in carrots (Daucus carota L)
Authors: Nyman E Margareta G‐L , Svanberg SJ Maria , Andersson Roger , Nilsson Torsten 
Published: November 2004

AbstractThe effects of cultivar (n = 4), root weight (n = 4), storage (5 months) and boiling (7 min) and their interactions on the content of dry matter and carbohydrates were studied and ranked in carrots. Boiling had the greatest effect and had an influence on all variables except the ratio between sucrose and the monosaccharides glucose and fructose. The choice of cultivar was also of great importance as regards glucose, fructose and sucrose content, while dietary fibre and dry matter were much less affected, or even unaffected, by this factor. Root weight and storage were consistently of less significance than boiling and cultivar. Thus dietary fibre solubility, fructose content and the ratio between sucrose and the monosaccharides glucose and fructose were independent of the root weight, while storage had no impact on the dry matter content. After storage the cultivar Lonto had lost more dry matter than the other cultivars (10% versus mean 1% for the others, P = 0.009) and the sugar ratio between sucrose and the monosaccharides glucose and fructose had increased in the cultivar Amarant, while it decreased in the other cultivars (P < 0.001). Furthermore, Amarant had a lower loss of sugars (35%) following boiling than the other cultivars (mean 39%, P = 0.002). Storage and boiling interacted concerning soluble and insoluble dietary fibre, fibre solubility and glucose content. It is concluded that the various factors (especially boiling and cultivar) gave rise to such differences in carbohydrate content and composition that they might be of nutritional importance. The results may thus provide a basis for selecting raw material when studying possible health effects of carrots. Copyright © 2004 Society of Chemical Industry
Production of lactic acid from vine‐trimming wastes and viticulture lees using a simultaneous saccharification fermentation method
Authors: Bustos Guadalupe , Moldes Ana Belén , Cruz José Manuel , Domínguez José Manuel 
Published: November 2004

AbstractAn effective process for the chemical–biotechnological utilization of trimming wastes of vineshoots, an agricultural waste with little use, is reported. Initial treatment with sulfuric acid (prehydrolysis) allowed the solubilization of hemicelluloses to give xylose and glucose‐containing liquors (suitable to make fermentation media for lactic acid production with Lactobacillus pentosus) and a solid phase containing cellulose and lignin. The solid residues from prehydrolysis were treated with NaOH in order to increase their cellulase digestibility. In the alkaline treatments, the effects of temperature (in the range, 50–130 °C), reaction time (30–120 min) and NaOH concentration (4–12 wt% of solution) on the composition and susceptibility to enzymatic hydrolysis of solid residues were assessed by means of an experimental plan with factorial structure. The lignin content decreased, whereas the susceptibility towards the enzymatic hydrolysis increased with temperature, reaction time and NaOH concentration within the tested range. Using the cellulosic residues achieved under the harsher conditions, favorable fermentation kinetics during simultaneous saccharification and fermentation carried out by L rhamnosus for lactic acid production were observed. The nutrients employed were the complete MRS broth and a cheaper medium developed using viticulture lees coming from the white wine making technology. In all cases the final lactic acid concentration achieved was similar, although the volumetric productivity was lower when using lees due to inhibitory effects over the enzymatic hydrolysis. Copyright © 2004 Society of Chemical Industry
Beneficial effect of the unsaponifiable matter from rice bran on oxidative stress in vitro compared with α‐tocopherol
Authors: Lee Jin‐Won , Lee Seog‐Won , Kim Min‐Kyung , Rhee Chul , Kim In‐Hwan , Lee Kwang‐Won 
Published: November 2004

AbstractUnsaponifiable matter (UM) was prepared from rice bran using n‐hexane extraction followed by removal of its fatty acid methyl ester with supercritical CO2 under heat‐stable conditions. The UM was made up of 1% of vitamin E isomers, 28% of γ‐oryzanol and 71% of uncharacterized compounds. The aim of this study was to determine the antioxidant activities of the UM, using α‐tocopherol (α‐T) as a positive control, by measuring the Fe3+‐reducing antioxidant power (FRAP), 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH•) free‐radical‐scavenging property and lipid peroxidation in rat liver microsomes. In addition, the effects of the UM on the tert‐butyl hydroperoxide (t‐BOOH)‐induced cytotoxicity in cultured rat hepatocytes were also investigated. In FRAP assay and DPPH• free‐radical‐scavenging assay, the results were expressed g−1α‐T or g−1 UM. The amount of UM used in lipid peroxidation assay and cytotoxicity assay was the amount required to have equal amounts of total vitamin E isomers in the sample and the control α‐T. The UM, as well as α‐T, exhibited significant antioxidant activities in FRAP, radical‐scavenging and membrane‐lipid oxidation. The FRAP value for total vitamin E isomers in the UM (TVEIUM) was 9.1 times higher than that for α‐T. In terms of their capacities to perform radical‐scavenging and lipid peroxidation, both TVEIUM and α‐T showed similar antioxidant activities. In experiments using cultured rat hepatocytes, the t‐BOOH‐induced lactate dehydrogenase release was significantly inhibited by the addition of 63.5 and 160 µg ml−1 of TVEIUM treatments (84 and 89%, respectively), and that of 63.5 and 160 µg ml−1 of α‐T treatment (88 and 93%, respectively). The antioxidant function against oxidative stress of the UM prepared from rice bran may extend its use to being a potential dietary supplement. Copyright © 2004 Society of Chemical Industry
Masticatory and non‐masticatory dental modifications in the epipalaeolithic necropolis of Taforalt (Morocco)
Authors: Bonfiglioli B. , Mariotti V. , Facchini F. , Belcastro M. G. , Condemi S. 
Published: November 2004

AbstractIn this study, we used standardized methods to investigate masticatory and non‐masticatory dental alterations (chipping, notches, interproximal grooves) in teeth from the epipalaeolithic necropolis of Taforalt (Morocco, about 12,000–11,000 BP). The particular distribution of some of the alterations could be related to avulsion of the upper central incisors, a systematic ritual characterizing all adult individuals of the necropolis. Because of this practice, the functions of the anterior teeth (cutting and tearing portions of food while eating, holding objects, etc.) likely shifted to the posterior teeth. Copyright © 2004 John Wiley & Sons, Ltd.
Adjuvant chemotherapy for the treatment of advanced pediatric nonrhabdomyosarcoma soft tissue sarcoma: The national cancer institute experience
Authors: Nathan Paul C. , Tsokos Maria , Long Lauren , Bernstein Donna , Wexler Leonard H. , Mackall Crystal L. , Helman Lee J. 
Published: November 2004

AbstractBackgroundThe survival of children and adolescents with advanced (unresectable or metastatic) nonrhabdomyosarcoma soft tissue sarcoma (NRSTS) is poor. In order to clarify the role of combining chemotherapy with aggressive local control using surgery and/or radiation, we reviewed our institutional experience with the treatment of advanced pediatric NRSTS.ProcedureWe reviewed the charts of all patients less than 21 years treated for an advanced NRSTS at the National Cancer Institute (NCI) between 1983 and 2003. Tumor pathology was confirmed and demographic, disease, and treatment data were abstracted. Survival was calculated using standard methods.ResultsOf the 25 patients who were treated over the study period, 15 had metastatic disease and 10 had unresectable or incompletely resected disease at presentation. Twenty‐one patients received chemotherapy consisting of the combination of vincristine, doxorubicin, cyclophosphamide, ifosfamide, and etoposide, and the remaining 4 received regimens that included doxorubicin. Twenty patients (80%) had a complete (5/25) or partial (15/25) response after chemotherapy alone. After the combination of chemotherapy and local control, 14 patients (56%) had a complete response (CR). The estimated 5‐year overall and event‐free survival (EFS) for all patients was 0.50 (standard error = 0.11) and 0.34 (standard error = 0.10), respectively.ConclusionsThe combination of chemotherapy with aggressive local control in this cohort of pediatric patients with advanced NRSTS yielded results comparable to those observed in patients with advanced sarcomas that are chemotherapy responsive. Prospective randomized trials are needed to quantify the contribution of chemotherapy and to determine the ideal regimen. Published 2004 Wiley‐Liss, Inc.
Fatigue resistance of continuous glass fiber/polypropylene composites: Temperature dependence
Authors: Bureau M. N. , Denault J. 
Published: November 2004

AbstractThe effect of testing temperature on the fatigue resistance of continuous glass fiber/polypropylene (CGF/PP) composites was studied. Fatigue resistance curves (or S‐N curves) were obtained at −40°C, 23°C and 50°C. Both on an absolute stress basis and on a normalized stress basis (with respect to the yield stress at the temperature considered), the S‐N curves showed that CGF/PP composites had excellent fatigue performance at 23°C and that their performance was actually improved at −40°C (below Tg of the PP matrix). The S‐N curves at 50°C showed that, although the composite flexural strength was reduced because of PP matrix softening, their fatigue performance remained relatively high, as it is controlled by the CGF reinforcement. Comparison with a CGF/thermoset isophthalic polyester composite of identical fiber architecture and similar flexural strength at 23°C indicated that the properties of the thermoplastic PP matrix provided improved fatigue resistance, both on an absolute and a normalized basis, especially below the glass transition temperature. It was concluded that the fact that the fatigue performance of the CGF/polyester composite is only weakly temperature‐dependent, while that of the CGF/PP composite is strongly temperature‐dependent, does not necessarily mean that it shows superior performance. Polym. Compos. 25:622–629, 2004. © 2004 Society of Plastics Engineers.
Influence of ethyl methacrylate content on the volume‐phase transition of temperature‐sensitive poly[(N‐isopropylacrylamide)‐co‐(ethyl methacrylate)] microgels
Authors: Ma Xiaomei , Huang Xiaobin , Zhu Lu , Zhao Xi'an , Tang Xiaozhen 
Published: November 2004

AbstractA novel series of temperature‐sensitive poly[(N‐isopropylacrylamide)‐co‐(ethyl methacrylate)] (p(NIPAM‐co‐EMA)) microgels was prepared by the surfactant‐free radical polymerization of N‐isopropylacrylamide (NIPAM) with ethyl methacrylate (EMA). The shape, size dispersity and volume‐phase transition behavior of the microgels were investigated by transmission electron microscopy (TEM), ultraviolet–visible (UV–Vis) spectroscopy, dynamic light scattering (DLS) and differential scanning calorimetry (DSC). The transmission electron micrographs and DLS results showed that microgels with narrow distributions were prepared. It was shown from UV–Vis, DLS and DSC measurements that the volume‐phase transition temperature (VPTT) of the p(NIPAM‐co‐EMA) microgels decreased with increasing incorporation of EMA, but the temperature‐sensitivity was impaired when more EMA was incorporated, causing the volume‐phase transition of the microgels to become more continuous. It is noteworthy that incorporation of moderate amounts of EMA could not only lower the VPTT but also enhance the temperature‐sensitivity of the microgels. The reason for this phenomenon could be attributed to changes in the complicated interactions between the various molecules. Copyright © 2004 Society of Chemical Industry
Biodegradable hollow microfibres to produce bioactive scaffolds
Authors: Lazzeri Luigi , Cascone Maria Grazia , Quiriconi Simone , Morabito Letterio , Giusti Paolo 
Published: November 2004

AbstractBiodegradable hollow microfibres containing particles loaded with specific active agents can be potentially employed to produce a special kind of substrate for tissue engineering, able to function as a scaffold and at the same time to act as a drug‐releasing system. Biodegradable hollow microfibres based on poly(lactic acid) were produced by a dry–wet spinning procedure. Drug‐loaded microparticles were prepared by a simple oil‐in‐water emulsion and entrapped inside the fibres. The morphology of both fibres and particles was investigated by scanning electron microscopy. The mechanical and thermal properties of the fibres were investigated by tensile tests and differential scanning calorimetry. In vitro tests were performed to evaluate the release of the drug from the fibres loaded with the particles Copyright © 2004 Society of Chemical Industry
Synthesis and characterization of an interpenetrating polymer network composed of poly(methacrylic acid) and poly(vinyl alcohol)
Authors: Kim Seon Jeong , Yoon Seoung Gil , Kim Sun I 
Published: November 2004

AbstractTemperature and pH‐responsive interpenetrating polymer network (IPN) hydrogels, constructed with poly(methacrylic acid) (PMAA) and poly(vinyl alcohol) (PVA), by a sequential IPN method, were studied. The characterization of IPN hydrogels was investigated by Fourier‐transform infrared spectroscopy, differential scanning calorimetry (DSC) and swelling under various conditions. The IPN hydrogels exhibited relatively high swelling ratios, in the range 230–380 %, at 25 °C. The swelling ratios of the PMAA/PVA IPN hydrogels were pH and temperature dependent. DSC was used for the quantitative determination of the amounts of freezing and non‐freezing water. The amount of free water increased with increasing PMAA content in the IPN hydrogels. Copyright © 2004 Society of Chemical Industry
Photoinitiator‐free UV grafting of styrene, a weak donor, with various electron‐poor vinyl monomers to polypropylene film
Authors: Ng Loo‐Teck , Nguyen Duc , Adeloju Samuel B 
Published: November 2004

AbstractThis study investigated the possibility of using styrene, a weak donor forming donor(D)/acceptor(A) pairs with electron‐poor (EP) vinyl monomers, for initiating spontaneous photopolymerization and photografting of the copolymers onto polypropylene. Maleic anhydride (MA), methyl methacrylate (MMA), methyl acrylate (MAC), dimethyl maleate (DMMA), acrylonitrile (AN) and acrylic acid (AA) were the EP monomers used. Grafting yields together with FTIR analyses were used to confirm the presence of grafting. Styrene/MMA and styrene/AN systems achieved significant grafting, but such levels of grafting were not observed in the styrene/MAC and styrene/DMMA systems. No grafting was observed for styrene/AA or styrene/MA systems, but the latter system underwent photopolymerization. The effect of solvents on grafting was evaluated on styrene/MMA and styrene/AN systems and dimethylformamide (DMF) was found to retard grafting of both D/A systems. In contrast, chloroform and methanol enhanced grafting of the styrene/AN system although these two solvents had no significant effect on the grafting of the styrene/MMA system. Copyright © 2004 Society of Chemical Industry
Graft copolymerization of itaconic acid onto chitin and its properties
Authors: Mostafa TB , Naguib HF , Sabaa MW , Mokhtar SM 
Published: November 2004

AbstractModification of chitin by grafting with itaconic acid (IA) was carried out using potassium persulfate as redox initiator. In complimentary experiments, grafting was performed using γ‐radiation. Grafting was confirmed by FTIR spectroscopy. The effect of monomer concentration, initiator concentration and copolymerization temperature on the percentage of grafting were studied. The effect of radiation dose was also investigated. Values for percentages of grafting of up to 300 % were reached. It was observed that the percentage of grafting increased with increasing monomer concentration and showed a tendency to level off at IA concentration of 0.1 mol l−1. The percentage of grafting increased with temperature up to 60 °C and then decreased. The solubility of the grafted chitin was studied in organic and inorganic solvents. The complexation of the grafted chitin with some cations, namely copper, nickel, cobalt, zinc and lead, was also investigated. The metal uptake was measured by UV spectroscopy. Thermogravimetric analysis of the grafted chitin was also studied. Copyright © 2004 Society of Chemical Industry
Preparation and characterization of soy protein plastics plasticized with waterborne polyurethane
Authors: Wang Niangui , Zhang Lina 
Published: November 2004

AbstractUtilizing anionic waterborne polyurethane (WPU) as a plasticizer, for the first time, we prepared new soy protein isolate (SPI) plastics. The WPU was prepared by using the emulsion‐extending‐chain method, and mixed with soy protein in aqueous dispersion. The mixture was cast, cured, pickled and hot‐pressed to form SPI plastics plasticized with WPU. The plastics sheets were characterized by infrared spectroscopy, scanning electron microscopy, ultraviolet spectrophotometry and wide‐angle X‐ray diffraction, and their properties were measured by using dynamic mechanical analysis, differential scanning calorimetry and tensile testing. The results revealed that SPI plastics plasticized with WPU possess good mechanical properties, such as a tensile strength (σb) of 7–19 MPa, water resistance (σb(wet)/σb(dry) = 0.4–0.5), optical transmittance and thermal stability, because of the good miscibility and strong interaction between WPU and SPI. With an increase of WPU content from 20 to 50 wt%, the elongation at break (εb) value of the sheets increased from 50 up to 150 %, and is much higher than that of the pure SPI sheet. WPU as a plasticizer can play an important role in improving the properties of SPI plastics. Copyright © 2004 Society of Chemical Industry
The relationship between mechanical properties and morphology of vibration‐injection‐molded polyethylene
Authors: Youbing Li , Xueqin Gao , Shaoyan Yuan , Yi Yuan , Jie Zhang , Wenti Ke , Kaizhi Shen 
Published: November 2004

AbstractThis paper introduces a novel melt vibration‐injection molding. The effect of mid‐frequency melt vibration on mechanical properties was introduced, and SEM, WAXD and DSC investigations had been employed to provide evidence for explaining the relationship between mechanical properties and morphology of vibration‐injection‐molded specimens. The results show that the effect of vibration frequency is very different from that of vibration pressure amplitude. At a given vibration pressure amplitude, the increase of vibration frequency is beneficial for obtaining preferential orientation, more perfect lamellae and enhanced mechanical properties. For a given vibration frequency, increase of vibration pressure amplitude is a pre‐requisite for the achievement of a large‐scale lamella, more pronounced orientation, increase of cyrstallinity and high strength of high‐density polyethylene, but part of the toughness is lost. Copyright © 2004 Society of Chemical Industry
Observations on Reproductive Health Programs in the Baltic States
Authors: Lazarus J.V. , Nadisauskiene R.J. , Liljestrand J. 
Published: November 2004

AbstractPublic attention in Sweden has been drawn to three neighboring states that recently joined the European Union: Estonia, Latvia, and Lithuania. At this historic moment, it seems instructive to look at how the rapidly reformed health sectors of these ex‐Soviet republics are responding to the vision of reproductive health articulated in Cairo 10 years ago. Reproductive health and rights have improved in these states in spite of recent reforms often acting to oppose improvement. Reforms such as the introduction of family medicine need continued adjustment, especially regarding antenatal care. One special challenge is the retention of essential mid‐level providers, such as midwives, as the mode of HIV transmission becomes increasingly sexual.
Conducting International Collaborative Research in Developing Nations
Authors: Geller S.E. , Patel A. , Niak V.A. , Goudar S.S. , Edlavitch S.A. , Kodkany B.S. , Derman R.J. 
Published: November 2004

AbstractInternational research partnerships bring together some of the best and the brightest in an effort to tackle global health problems. Such collaborations also pose complex challenges, such as maintaining ethical principles in the conduct of research in developing nations. In implementing a randomized clinical trial to reduce postpartum hemorrhage (PPH) during childbirth in rural India, U.S. and Indian collaborators addressed three such issues: the appropriateness of an ethical randomized controlled trial in the developing world, the inclusion of a placebo arm, and the relevance of informed consent in a semiliterate rural population.