bluuebunny/crossref_metadata_2025 huggingface dataset:
FORAGE RESPONSE TO COPPER FERTILIZATION ON TWO BRITISH COLUMBIA CENTRAL INTERIOR SOILS
Authors: BOMKE A. A. , LOWE L. E.
Published: March 2010

Copper deficiencies have been reported in cattle in the Fort Fraser-Vanderhoof region of British Columbia and a subsequent forage Cu survey showed widespread low-Cu forages. A series of greenhouse pot studies was conducted to assess the effectiveness of Cu fertilization in increasing yields and Cu concentrations in crops grown on two soils, a Vanderhoof silty clay loam and Welch sandy loam. Copper concentrations in whole-plant barley, bromegrass and alsike clover were increased by Cu fertilization at rates of 2.5 and 10 μg∙g−1. However, yields were not affected. Copper application at 2.5 μg∙g−1 was sufficient to increase Cu concentrations in whole-plant barley and bromegrass above the 4 μg∙g−1 critical value for beef cattle. Alsike clover contained adequate Cu without Cu addition. DTPA Cu concentrations over 1.8 μg∙g−1 were required to produce bromegrass and whole-plant barley Cu concentrations in excess of 4 μg∙g−1. The Vanderhoof silty clay loam provided more available Cu at the 0 and 2.5 μg∙g−1 Cu application rates, but Cu fertilization at both rates increased Cu uptake over the 0 Cu treatments to a greater extent in the Welch sandy loam. Phosphorus fertilization at 25 μg∙g−1 increased whole-plant barley Cu concentrations slightly. Fertilization with Cu or increased use of legumes are possible approaches to the problem of Cu deficiencies in forage-based beef cattle production in this region. Key words: Bromegrass, alsike, whole-plant barley, DTPA Cu, Cu × P fertilization, beef forage system
TOTAL FLUORINE IN CSSC REFERENCE SOIL SAMPLES
Authors: SCHUPPLI P. A.
Published: March 2010

Total fluorine was measured in a variety of Canadian soils using the lithium metaborate-nitric acid solution technique in conjunction with the fluoride electrode. Total fluorine ranged from 90 to 1000 mg∙kg−1. Key words: Soil fluorine analysis, fluoride electrode, CSSC reference soil samples
A STANDARD CURVE FOR INTER-SITE COMPARISON OF CELLULOSE DEGRADATION USING THE COTTON STRIP METHOD
Authors: HILL M. O. , LATTER P. M. , BANCROFT G.
Published: March 2010

Cotton cloth was buried in contrasting soils for various lengths of time until close to physical disintegration. Cellulose degradation was assessed by comparing the tensile strength of cloth after recovery with that before burial. A curve was derived for loss of tensile strength of cloth, when rotting under constant conditions. The curve was linearized by a mathematical technique analogous to taking logarithms when there is exponential decay. By means of the linearization, rates of degradation were compared between widely differing sites, using both our own data and reworked data from the literature. The time to 50% loss of tensile strength ranged from 3.2 days in an incubator at 29 °C to 1.2 yr in an arctic tundra. A mathematical model of the decay process suggests that the rate of degradation depends mainly on the physico-chemical environment of the cotton in the soil, and is insensitive to the size of microbial inoculum. Key words: Decomposition, cotton strips, site comparison, cellulose degradation, soil burial test
PARAQUAT-INDUCED CHANGES IN SELECTED RHIZOBIA AND AGROBACTERIA
Authors: ROSLYCKY E. B.
Published: March 2010

Adaptations of eight strains of rhizobia from seven cross-inoculation groups and of two agrobacteria from two species to paraquat, in concentrations up to 20 000 μg∙mL−1, affected 11 of the 40 properties studied, including carbohydrate, nitrogen, sulfur, and other metabolism. The number of characteristics altered varied among the bacteria without species or group affiliation. Of the total of 18 changes, 13 occurred in Rhizobium meliloti 22 and R. trifolii 7 and 42, while R. leguminosarum 56, R. lupini 112, R. japonicum 80, cowpea strain 131, and Agrobacterium tumefaciens A6-K1 had only one. Rhizobium phaseoli 95 and A. radiobacter R-590 remained unaffected. Generally, the adapted organisms produced lower nephelometric growth and manometric respiration rates at 0 and 200 μg of paraquat∙mL−1, relative to the herbicide-free parent controls. Tolerance of R. trifolii 7 to NaCl increased from 1% to 5% (wt/vol). The findings suggest that paraquat may have affected cell permeability, adaptive and/or constitutive enzymes in these bacteria. Key words: Rhizobia, agrobacteria, adaptations, physiology, paraquat and herbicides
PROTONATION OF SOIL PARTICLE SURFACES: KINETICS
Authors: ARINGHIERI R. , PARDINI G.
Published: March 2010

A kinetic process was investigated by which H+ ions interact with soil surfaces giving rise to a positive electric charge distribution. A two-step process took place in the range of time examined. A first rapid step was always followed by a relatively slower step, and a first-order kinetic equation was applied to describe this second step of the process. The values of specific rate, calculated at different initial H+ ion activities and two different amounts of soil, indicated that a diffusion-controlled mechanism was governing the rate of the slower step and consequently the overall rate of the process. Protonation and deprotonation specific rates were also calculated in the presence of varying concentrations of supporting electrolytes. It was found that the specific rate was dependent on either the structure of the electric double layer formed on soil surfaces in the presence of electrolyte, or on the particular surface electric charge distribution of the examined soil. Key words: Protonation kinetics, specific rate, diffusion phenomena, permanent charge, pH-dependent charge, diffuse double layer
FIELD EVALUATION OF THE EFFECTS OF A UREASE INHIBITOR AND CROP RESIDUES ON UREA HYDROLYSIS, AMMONIA VOLATILIZATION AND YIELD OF CORN
Authors: TOMAR J. S. , KIRBY P. C. , MacKENZIE A. F.
Published: March 2010

The effects of a urease inhibitor and crop residues on urea hydrolysis, NH3 volatilization and silage corn (Zea mays L.) yield were assessed on an Ormstown silty clay loam soil under field conditions. Chopped timothy straw (Phleum pratense L.) was spread on the soil surface at 0 and 4600 kg∙ha−1. Urea solutions treated with 0, 0.25, 0.50, 1.0, 2.0 and 3.74 kg∙ha−1 of an urease inhibitor phenylphosphorodiamidate (supplied by The Crop Science Laboratory, Allied Corporation, Solvay, N.Y.), and NH4NO3 solutions with no inhibitor were added as dribble bands to the soil surface at 0 and 75.0 kg N∙ha−1. Urea-N remaining in the soil over a period of 14 days following urea application was measured. The extent of NH3 volatilization was assessed by capturing and measuring NH4–N using plastic cylinders (micro-plots) over a period of 17 days following urea application. Dry matter yield of corn was obtained 114 days after planting. Hydrolysis of urea was relatively rapid and 3–26% of the applied N was hydrolyzed within 2 days following urea application to the soil. The higher rates of inhibitor application (2.0 and 3.74 kg∙ha−’) tended to reduce urea hydrolysis. The inhibitor rate effect increased with time though not always significantly. More than 50% of the added N was still present as urea after 4 days with some exceptions. At day 8, the amount of N that was present as urea ranged from 4 to 28% for the lower rates and from 20 to 37% for the higher rates of inhibitor applied. Almost all the added urea had disappeared by 14 days. Measured losses of NH3 by volatilization within 17 days never exceeded 1% of the fertilizer N. Addition of N resulted in 14% increase in dry matter yield of corn. Nitrogen source, crop residues and urease inhibitor had no appreciable effect on crop yield. Key words: Urea-N transformations, urea fertilizer, NH3 losses, urease activity, straw
EXTRACTION AND COLORIMETRIC DETERMINATION OF ELEMENTAL SULFUR IN ORGANIC HORIZONS OF FOREST SOILS
Authors: MAYNARD D. G. , ADDISON P. A.
Published: March 2010

A method is proposed for determining elemental S (S°) in organic horizons of forest soils. Elemental sulfur is extracted from the soil with acetone and assayed by a colorimetric method. The procedure is a modification of several existing methods and allows for the extraction of all forms of S°. It also reduces the interference of colored extracts from forest litter. The detection limit is 100 mg∙kg−1 (1 mg S°∙mL−1 of solution) and S° concentrations in excess of 50 000 mg∙kg−1 have been measured. The recovery of S° is approximately 90%. The method is suitable for determining S° in organic forest soils with a wide range of S° concentrations and where a high degree of accuracy and precision is not required. It is rapid and suitable for routine analysis in laboratories without specialized equipment. Key words: Elemental sulfur, forest soil analysis, organic horizon
Osteoradionecrosis Complicating Mandibulotomy
Authors: Trupti Kolur , Vishal Rao , Chavan Purushottam , Kavita Umesh , Ashok Shenoy
Published: March 2010

Osteoradionecrosis (ORN) of the mandible is a well acknowledged entity following radiotherapy for oral cancers. Mandibular surgery prior to radiotherapy adds an additional risk factor for osteoradionecrosis. Management of these cases poses various hurdles including added morbidity, additional cost for treatment of ORN and suboptimal dose delivery to the tumor bed. This case reports elaborates the issues related to mandibular surgery in patients requiring adjuvant radiotherapy, precautions to be taken and the management of ORN in a postsurgical setting.
An Unusual Case of Epidermal Inclusion Cyst of Maxilla
Authors: Abhishek Vaidya , Arpit Sharma , Jyoti Dabholkar , Abhijit Raut
Published: March 2010

Introduction

Epidermal inclusion cyst is a relatively common condition usually associated with trauma, with characteristic presentation, and seen in the extremities. However, it is an uncommon entity in the head and neck region.

Objective

The purpose of this paper is to report the unusual presentation of epidermal inclusion cyst in the maxilla without any definitive history of trauma and to review the concerned English language literature.

Conclusion

In the absence of any definitive history of trauma, only a thorough clinical examination along with characteristic radiological imaging and histopathological findings will help in diagnosing epidermal inclusion cyst.
Platysma Sign—A Clinical Manifestation of Infiltration of Platysma and the Subcutaneous Tissue by Large Neck Node
Authors: Prakash Agarwal Jai , Pankaj Chaturvedi
Published: March 2010

We propose a simple clinical sign that is seen in certain patients with bulky nodal metastases. The fundamental basis of this sign is the direct infiltration of platysma by the nodal mass causing contracture of the muscle fibers of platysma called “Platysma sign”. The exact definition of this sign is “ puckering of the platysma and the overlying skin like an inverted Japanese fan”. This puckering always happens below the level of nodes and finishes at the level of the clavicle. This clinical sign can serve as an instant reminder to the clinician and avoid oversight of the skin/platysma infiltration. Assessment of the integrity of the neck skin overlying a large neck nodes must be undertaken while examining a head and neck cancer patient with bulky neck metastasis. Infiltration of platysma or the skin is an important finding in the staging and treatment of the neck disease.
A CdSe Nanowire/Quantum Dot Hybrid Architecture for Improving Solar Cell Performance
Authors: Yu Yanghai , Kamat Prashant V. , Kuno Masaru
Published: March 2010

Incorporating colloidal CdSe quantum dots (QDs) into CdSe nanowire (NW)‐based photoelectrochemical solar cells increases their incident‐photon‐to‐carrier conversion efficiencies (IPCE) from 13% to 25% at 500 nm. While the effect could, in principle, stem from direct absorption and subsequent carrier generation by QDs, the overall IPCE increase occurs across the entire visible spectrum, even at wavelengths where the dots do not absorb light. This beneficial effect originates from an interplay between NWs and QDs where the latter fill voids between interconnected NWs, providing electrically accessible conduits, in turn, enabling better carrier transport to electrodes. The presence of QDs furthermore reduces the residual polarization anisotropy of random NW networks. Introducing QDs therefore addresses an important limiting constraint of NW photoelectrochemical solar cells. The effect appears to be general and may aid the future design and implementation of other NW‐based photovoltaics.
The prenatal origins of lung cancer. I. The fetus
Authors: Eriksson Johan G. , Thornburg Kent L. , Osmond Clive , Kajantie Eero , Barker David J.P.
Published: March 2010

People differ in their susceptibility to developing cancer on exposure to carcinogens such as tobacco. What causes this is largely unknown. One possibility is that it is determined by nutritional influences during development that permanently change the structure and function of the baby's body. We studied an older and a younger cohort, totaling 20,431 men and women, born in Helsinki during 1924–1933 and 1934–1944. Their body size at birth had been recorded. Of them, 385 had developed lung cancer. Smoking history was known for 6,822 people. At birth, babies who later developed lung cancer had a high ponderal index (birthweight/length3). This association was confined to people whose mother's height was below the median. Among these people in the older cohort, the hazard ratio associated with a ponderal index >30 kg/m3 was 3.1 (95% CI 1.6–5.9), in comparison to those with a ponderal index of 26 kg/m3 or less (P for trend < 0.001). The equivalent figures for the younger cohort were 2.9 (1.2–7.0, P for trend = 0.001) and this association was independent of smoking. We suggest that a high ponderal index in babies born to short mothers is the result of low amino acid delivery to the fetus in relation to glucose delivery. We hypothesize that this impairs the development of the babies' antioxidant systems and makes them vulnerable to oxidative stress in later life. This is the first evidence that fetal programming may determine vulnerability to carcinogens in humans. humans. Am. J. Hum. Biol. 2010. © 2010 Wiley‐Liss, Inc.
The prenatal origins of lung cancer. II. The placenta
Authors: Barker David J.P. , Thornburg Kent L. , Osmond Clive , Kajantie Eero , Eriksson Johan G.
Published: March 2010

We have shown that people who were short at birth in relation to their weight are at increased risk of lung cancer. We suggested that this reflected low amino acid–high glucose delivery to the fetus and that this impaired the development of its antioxidant systems and made it vulnerable to tobacco smoke and other carcinogens in later life. Transfer of amino acids and glucose from mother to fetus depends on the placenta. We here examine how maternal and placental size are related to lung cancer. We studied two cohorts, totaling 20,431 people, born in Helsinki during 1924–1944. Their body size at birth and maternal body size had been recorded together with the weight of the placenta and two diameters of its surface. Of them, 385 had developed lung cancer. Three different maternal–placental–fetal phenotypes were associated with lung cancer. Common to each was a short mother and a newborn baby that was short in relation to its weight. Lung cancer was associated with either a small or a large placental surface area. In the three phenotypes, the hazard ratios associated with a 100 cm2 increase in placental surface were 0.36 (95% CI 0.14 to 0.87, P = 0.02), 2.31 (1.45 to 3.69, P < 0.001) and 2.04 (1.08 to 3.86, P = 0.03). We conclude that three different maternal–placental phenotypes were associated with later lung cancer. We suggest that each led to low amino acid‐normal glucose transfer to the fetus, reflected in a newborn baby that was short in relation to its weight. Am. J. Hum. Biol. 2010. © 2010 Wiley‐Liss, Inc.
Toward quantifying the usage costs of human immunity: Altered metabolic rates and hormone levels during acute immune activation in men
Authors: Muehlenbein Michael P. , Hirschtick Jana L. , Bonner Julia Z. , Swartz Ann M.
Published: March 2010

There is a paucity of data on the energetic demands of human immune functions, despite the fact that both clinical medicine and evolutionary biology would benefit from further clarification of these costs. To better understand the energetic requirements of mounting a mild immune response, as well as some of the major hormonal changes underlying these metabolic changes, we examined changes in resting metabolic rate (RMR) and hormones during and after respiratory tract infection in young adult men. An epidemiologic passive detection design was used to recruit 25 nonfebrile subjects naturally infected with respiratory tract pathogens. Symptomology, percent body fat, RMR, salivary testosterone and cortisol, and other information were collected at a minimum of three time points during and after convalescence. Comparisons of the differences in RMR, testosterone, and cortisol between sampling days within individual cases were made using paired t‐tests. Participants experienced 8% higher RMR during illness, and a subset of these men experienced a mean increase greater than 14%. The participants also experienced 10% lower testosterone levels during illness, and a subset of these participants experienced a mean decrease of 30%, although cortisol levels did not change significantly. These results document elevated RMR following natural pathogen exposure in adult humans, demonstrating that even mild immune reactions can elicit significant increases in energy expenditure. Understanding the costs of immunity and the immunomodulatory actions of hormones are central to understanding the role of immunity in human life history evolution. Am. J. Hum. Biol. 2010. © 2010 Wiley‐Liss, Inc.
Testosterone, physical activity, and somatic outcomes among Filipino males
Authors: Gettler Lee T. , Agustin Sonny S. , Kuzawa Christopher W.
Published: March 2010

Testosterone (T) facilitates male investment in reproduction in part through its anabolic effects on skeletal muscle. Traits like muscle and strength are energetically costly but are believed to enhance competitive ability in humans and other mammals. However, there are limited data on relationships between T and somatic outcomes in lean, non‐western populations. We evaluate relationships between waking and pre‐bed salivary T and adiposity, fat‐free mass (FFM), arm muscle area (AMA), and grip strength (GS) in a large, population‐based birth cohort of young adult Filipino males (20.8–22.6 years, n = 872). Data were collected as part of the Cebu Longitudinal Health and Nutrition Survey. Neither waking nor evening T predicted FFM, AMA, or GS. However, there were borderline or significant interactions between T and basketball playing (the most common team sport) and weight lifting as predictors of outcomes: higher waking T predicted higher FFM (activity × T interaction P < 0.01), AMA (interaction P < 0.1), and GS (interaction P < 0.02) among frequent basketball players, and GS (interaction P < 0.09) among the smaller sample of weight lifters. In contrast to clinical studies, but consistent with findings in several subsistence‐level populations, T was positively related to adiposity in these lean young males, suggesting that energy status might regulate circulating T. Our findings support a role of the prewaking rise in T as a determinant of energetic allocation to lean mass and strength in the context of repeated muscular use and support the hypothesized role of T as a mediator of investment in costly somatic traits in human males. Am J Phys Anthropol 142:590–599, 2010. © 2010 Wiley‐Liss, Inc.
Prezygapophyseal articular facet shape in the catarrhine thoracolumbar vertebral column
Authors: Russo Gabrielle A.
Published: March 2010

Two contrasting patterns of lumbar vertebral morphology generally characterize anthropoids. “Long‐backed” monkeys are distinguished from “short‐backed” apes [Benton: The baboon in medical research, Vol. 2 (1967:201)] with respect to several vertebral features thought to afford greater spinal flexibility in the former and spinal rigidity in the latter. Yet, discussions of spinal mobility are lacking important functional insight that can be gained by analysis of the zygapophyses, the spine's synovial joints responsible for allowing and resisting intervertebral movements. Here, prezygapophyseal articular facet (PAF) shape in the thoracolumbar spine of Papio, Hylobates, Pongo, Gorilla, and Pan is evaluated in the context of the “long‐backed” versus “short‐backed” model. A three‐dimensional geometric morphometric approach is used to examine how PAF shape changes along the thoracolumbar vertebral column of each taxon and how PAF shape varies across taxa at corresponding vertebral levels. The thoracolumbar transition in PAF shape differs between Papio and the hominoids, between Hylobates and the great apes, and to a lesser extent, among great apes. At the level of the first lumbar vertebra, the PAF shape of Papio is distinguished from that of hominoids. At the level of the second lumbar vertebra, there is variation to some extent among all taxa. These findings suggest that morphological and functional distinctions in primate vertebral anatomy may be more complex than suggested by a “long‐backed” versus “short‐backed” dichotomy. Am J Phys Anthropol 142:600–612, 2010. © 2010 Wiley‐Liss, Inc.
Tolerant food sharing and reciprocity is precluded by despotism among bonobos but not chimpanzees
Authors: Jaeggi Adrian V. , Stevens Jeroen M.G. , Van Schaik Carel P.
Published: March 2010

Tolerant food sharing among human foragers can largely be explained by reciprocity. In contrast, food sharing among chimpanzees and bonobos may not always reflect reciprocity, which could be explained by different dominance styles: in egalitarian societies reciprocity is expressed freely, while in more despotic groups dominants may hinder reciprocity. We tested the degree of reciprocity and the influence of dominance on food sharing among chimpanzees and bonobos in two captive groups. First, we found that chimpanzees shared more frequently, more tolerantly, and more actively than bonobos. Second, among chimpanzees, food received was the best predictor of food shared, indicating reciprocal exchange, whereas among bonobos transfers were mostly unidirectional. Third, chimpanzees had a shallower and less linear dominance hierarchy, indicating that they were less despotic than bonobos. This suggests that the tolerant and reciprocal sharing found in chimpanzees, but not bonobos, was made possible by the absence of despotism. To investigate this further, we tested the relationship between despotism and reciprocity in grooming using data from an additional five groups and five different study periods on the main groups. The results showed that i) all chimpanzee groups were less despotic and groomed more reciprocally than bonobo groups, and ii) there was a general negative correlation between despotism and grooming reciprocity across species. This indicates that an egalitarian hierarchy may be more common in chimpanzees, at least in captivity, thus fostering reciprocal exchange. We conclude that a shallow dominance hierarchy was a necessary precondition for the evolution of human‐like reciprocal food sharing. Am J Phys Anthropol 143:41–51, 2010. © 2010 Wiley‐Liss, Inc.
Waddling and toddling: The biomechanical effects of an immature gait
Authors: Cowgill Libby W. , Warrener Anna , Pontzer Herman , Ocobock Cara
Published: March 2010

Femoral shape changes during the course of human growth, transitioning from a subcircular tube to a teardrop‐shaped diaphysis with a posterior pilaster. Differences between immature and mature bipedalism and body shape may generate different loads, which, in turn, may influence femoral modeling and remodeling during the course of the human lifespan. This study uses two different approaches to evaluate the hypotheses that differences in gait between young and mature walkers result in differences in ground reaction forces (GRFs) and that the differences in loading regimes between young children and adults will be reflected in the geometric structure of the midshaft femur. The results of this analysis indicate that GRFs differ between young walkers and adults in that normalized mediolateral (ML) forces are significantly higher in younger age groups. In addition, these differences between children and adults in the relative level of ML bending force are reflected in changes in femoral geometry during growth. During the earlier stages of human development, immature femoral diaphyses are heavily reinforced in approximately ML plane. The differences in gait between mature and immature walkers, and hence the differences in femoral shape, are likely partially a product of a minimal bicondylar angle and relatively broad body in young children. Am J Phys Anthropol 143:52–61, 2010. © 2010 Wiley‐Liss, Inc.
An improved practical Pd/C‐catalyzed Sonogashira cross‐coupling reaction for the synthesis of liquid crystals of trans‐cyclohexyltolans
Authors: Shang Hongyong , Hua Ruimao , Zheng Qingwei , Zhang Jianli , Liang Xiao , Zhu Qiming
Published: March 2010

An improved practical synthesis of liquid crystals of trans‐cyclohexyltolans by Sonogashira cross‐coupling reaction of 1‐iodo‐4‐(trans‐4‐alkylcyclohexyl)benzene with aromatic terminal alkynes in the presence of Pd/C (palladium on activated carbon) as low as 0.03 mol% of Pd and CuI (2 mol%) in a mixture solvent of acetone–water (5:2 in volume) is described. The liquid crystals could be obtained in high yields as a solid with excellent purity by simple filtration, and the filtrate could be reused several times while still retaining high catalytic activity. Copyright © 2010 John Wiley & Sons, Ltd.
Fabrication and properties of PLLA‐gelatin nanofibers by electrospinning
Authors: Yan Su , Xiaoqiang Li , Shuiping Liu , Hongsheng Wang , Chuanglong He
Published: March 2010

Poly(L‐lactide acid)‐blend‐gelatin (PLLA‐gelatin) nanofibers were successfully fabricated by means of electrospinning. The different material components characterizing the properties of electrospun PLLA/G nanofibers were measured and the effect of PLLA weight ratios on such properties as morphologies, physical and chemical structure and mechanical profiles were analyzed. It was found that the fibers diameter increases and the ultimate tension‐stress enhances with increased PLLA weight ratio. The analysis of X‐ray diffractometry, differential scanning calorimetry, and Fourier‐transform infrared spectra demonstrated that the resultant nanofibers from electrospinning of PLLA‐gelatin solution are simple blends of these two components. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
The single fiber composite test: A comparison of E‐glass fiber fragmentation data with statistical theories
Authors: Holmes Gale A. , Kim Jae Hyun , Leigh Stefan , McDonough Walter
Published: March 2010

The exact theories advanced by Curtin6and Hui et al.7to describe the fiber break evolution process in single fiber composites are found to be incorrect when compared with experimental data. In contrast to theoretical predictions where the matrix is assumed to be elastic perfectly plastic, experimental data indicate that the sizes of the fragment lengths that survive to saturation decrease as the strain is increased. It is also shown that the break locations at saturation are uniform along the length of the fiber specimens, with the uniformity apparently being independent of interfacial shear strength, fiber type, matrix type, and fiber–fiber interactions. The theory of uniform spacings gives an explicit distribution function for the ordered fragment lengths. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Synthesis and characterization of amphiphilic pluronic (F68)‐1,2‐dipalmitoyl‐sn‐glycero‐3‐phosphoethanolamine copolymers and their micelles as a drug carrier
Authors: Wang Tiewei , Wu Yan , Zeng Ai Jun
Published: March 2010

A new Pluronic (F68)‐1,2‐dipalmitoyl‐sn‐glycero‐3‐phosphoethanolamine (DPPE) (Pluronic (F68)–DPPE) copolymer was synthesized with Pluronic (F68) and DPPE. The chemical structure and physical properties of copolymers were determined by FTIR, 1H NMR, 13C NMR, 31P NMR, and TGA. Environmental scanning electron microscopy, fluorescence spectroscopy, and dynamic light scattering method confirmed the formation of copolymeric micelles of Pluronic (F68)‐DPPE. To estimate the feasibility as novel drug carriers, the copolymer micelles were prepared by the phase separation dialysis method. Amphotericin B as a lipophilic model drug was incorporated into copolymeric micelles and the drug release behavior was investigated. It was found that the chemical composition of the micelle was a key factor in controlling micelles size, drug‐loading content, and drug release behavior. As DPPE segment weight ratio increased, the micelle size and drug‐loading content increased, and the drug release rate decreased. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Effect of dicarboxylic acids on the performance properties of polyurethane dispersions
Authors: Athawale Vilas D. , Kulkarni Mona A.
Published: March 2010

A series of low molecular weight linear polyester polyols were synthesized by using various diacids, neopentyl glycol, as a diol, and a trimethylol propane, as a branching monomer. Polyurethane dispersions were prepared primarily from isophorone diisocyanate, polyester polyol, and dimethylol propionic acid, as potential ionic center for water dispersibility, and were subsequently chain extended with ethylene diamine. The effect of polyester polyols based on variable diacids, on the physico‐chemical and thermal properties of polyurethane dispersions were evaluated by hardness, flexibility, impact resistance, solvent resistance, thermogravimetric analysis, and differential scanning calorimetry. Particle size was evaluated by particle size analyzer. It was observed that the number of alkylene groups present in the polyester polyol soft segment in addition to its molecular weight had a pronounced effect on the particle size, physico‐chemical, and thermal properties. With a proper selection of the soft segment, it is possible to fine‐tune properties of aqueous polyurethane dispersion coatings with respect to the final application. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Effects of solvent basicity on free radical polymerizations of N,N′‐bismaleimide‐4,4′‐diphenylmethane initiated by barbituric acid
Authors: Su Heng‐Lei , Hsu Jung‐Mu , Pan Jing‐Pin , Wang Tsung‐Hsiung , Chern Chorng‐Shyan
Published: March 2010

The polymerizations of N,N′‐bismaleimide‐4,4′‐diphenylmethane (BMI) initiated by barbituric acid (BTA) carried out in a variety of solvents at 130°C were studied. The nitrogen‐containing cyclic solvents such as N‐methyl‐2‐pyrrolidinone acted as a catalyst to promote the formation of the three‐dimensional crosslinked network structure. By contrast, the polymerization in a cyclic solvent that did not contain nitrogen such as γ‐butyrolactone resulted in nil gel content. The higher the solvent basicity, the larger the amount of insoluble polymer species formed. The molar ratio of BTA to BMI also played an important role in the polymerizations. The resultant polymers, presumably having a hyper‐branched structure, exhibited much narrower molecular weight distributions than those prepared by conventional free radical polymerizations. The BMI polymerizations using BTA as the initiator could not be adequately described by conventional free radical polymerization mechanisms. A polymerization mechanism that took into account the generation of a ketone radical pair between BTA and BMI and the subsequent initiation, propagation and termination reactions was proposed. It was concluded that the nitrogen‐containing cyclic solvents were capable of participating in the ketone radical pair formation process, thereby increasing the extent of polymer crosslinking reactions. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Viscoelastic and thermal properties of woven‐sisal‐fabric‐reinforced natural‐rubber biocomposites
Authors: Jacob Maya , Jose Jesmy , Jose Seno , Varughese K. T. , Thomas Sabu
Published: March 2010

Textile–rubber biocomposites were prepared by the reinforcement of natural rubber with woven sisal fabric. The viscoelastic properties of the composites were analyzed at different frequencies. Sisal fabric was subjected to different chemical modifications, such as mercerization, silanation, and thermal treatment, and the influences of the modifications on the dynamic mechanical properties were analyzed. The storage modulus was found to increase with reinforcement of natural rubber with woven sisal fabric. The chemical modification of the sisal fabric resulted in a decrease in the storage modulus. The damping factor was found to decrease with chemical treatment, and the gum compound exhibited maximum damping characteristics. The thermal stabilities of the composites were also analyzed by thermogravimetric studies. Scanning electron microscopy studies were performed to evaluate the morphology of the fabric–matrix interface.© 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Genetic variability of Austropotamobius italicus in the Marches region: implications for conservation
Authors: Cataudella Rosaria , Paolucci Marina , Delaunay Carine , Ropiquet Anne , Hassanin Alexandre , Balsamo Maria , Grandjean Frédéric
Published: March 2010

Ten populations of Austropotamobius italicus from the Marches region (Central Italy), two populations from the Appennines of Calabria and Basilicata (Southern Italy) and four populations from Friuli Venezia Giulia region were sampled to elucidate the geographical pattern of genetic variability in relation to recent and historical factors.

A total of nine COI haplotypes belonging to three separate lineages have been characterized. Both lineage A (Northern Marches region) and C (Friuli Venezia Giulia region) were represented by one haplotype and were related to the Istria 1 peninsula and SouthAlps/Western Balkans lineages respectively. The lineage B included seven haplotypes belonging to the Appenines lineage.

Two hypotheses on the origin of individuals belonging to the Istrian lineage in Marches are discussed: (i) a natural colonization from the Istria peninsula refugia by migrating westwards across the bridge between the Istria peninsula and Italy, (ii) an anthropogenic origin. Based on 16S rRNA sequences, the taxonomic status of lineage B and C, defined from COI mtDNA markers, belongs to A. i. meridionalis and that of lineage A belongs to A. i. carsicus. The existence of a complex geographic structure between Marches populations (Φst=0.66) of A. i. meridionalis should be further considered in conservation management. Copyright © 2010 John Wiley & Sons, Ltd.
An ecosystem‐scale predictive model of coastal seagrass distribution
Authors: Grech A. , Coles R. G.
Published: March 2010

Maintaining ecological processes that underpin the functioning of marine ecosystems requires planning and management of marine resources at an appropriate spatial scale.

The Great Barrier Reef World Heritage Area (GBR) is the world's largest World Heritage Area (approximately 348 000 km2) and second largest marine protected area. It is difficult to inform the planning and management of marine ecosystems at that scale because of the high cost associated with collecting data. To address this and to inform the management of coastal (approximately 15 m below mean sea level) habitats at the scale of the GBR, this study determined the presence and distribution of seagrass by generating a Geographic Information System (GIS)‐based habitat suitability model.

A Bayesian belief network was used to quantify the relationship (dependencies) between seagrass and eight environmental drivers: relative wave exposure, bathymetry, spatial extent of flood plumes, season, substrate, region, tidal range and sea surface temperature. The analysis showed at the scale of the entire coastal GBR that the main drivers of seagrass presence were tidal range and relative wave exposure. Outputs of the model include probabilistic GIS‐surfaces of seagrass habitat suitability in two seasons and at a planning unit of cell size 2 km×2 km.

The habitat suitability maps developed in this study extend along the entire GBR coast, and can inform the management of coastal seagrasses at an ecosystem scale. The predictive modelling approach addresses the problems associated with delineating habitats at the scale appropriate for the management of ecosystems and the cost of collecting field data. Copyright © 2010 John Wiley & Sons, Ltd.
Synthesis and in‐vitro Cytotoxicity of Poly‐functionalized 4‐(2‐Arylthiazol‐4‐yl)‐4H‐chromenes
Authors: Mahmoodi Majid , Aliabadi Alireza , Emami Saeed , Safavi Maliheh , Rajabalian Saeed , Mohagheghi Mohammad‐Ali , Khoshzaban Ahad , Samzadeh‐Kermani Alireza , Lamei Navid , Shafiee Abbas , Foroumadi Alireza
Published: March 2010

A new series of 4‐aryl‐4H‐chromenes bearing a 2‐arylthiazol‐4‐yl moiety at the 4‐position were prepared as potential cytotoxic agents. The in‐vitro cytotoxic activity of the synthesized 4‐aryl‐4H‐chromenes was investigated in comparison with etoposide, a well‐known anticancer drug, using MTT colorimetric assay. Among them, the 2‐(2‐chlorophenyl)thiazol‐4‐yl analog 4b showed the most potent activity against nasopharyngeal epidermoid carcinoma KB, medulloblastoma DAOY, and astrocytoma 1321N1, and compound 4d bearing a 2‐(4‐chlorophenyl)thiazol‐4‐yl moiety at the 4‐position of the chromene ring exhibited the best inhibitory activity against breast cancer cells MCF‐7, lung cancer cells A549, and colon adenocarcinoma cells SW480 with IC50 values less than 5 μM. The ability of compound 4b to induce apoptosis was confirmed in a nuclear morphological assay by DAPI staining in the KB and MCF‐7 cells.
The histopathologic associates of neurometabolite abnormalities in fatal neuropsychiatric systemic lupus erythematosus
Authors: Brooks William M. , Sibbitt Wilmer L. , Kornfeld Mario , Jung Rex E. , Bankhurst Arthur D. , Roldan Carlos A.
Published: March 2010

Objective

To determine the histopathologic basis of altered brain neurometabolites in neuropsychiatric systemic lupus erythematosus (NPSLE).

Methods

Brain neurometabolite concentrations in a 20‐voxel area of the brain were determined premortem by magnetic resonance spectroscopy (MRS) in 7 individuals with NPSLE. Absolute concentrations of neurometabolite for N‐acetylaspartate (NAA), choline, creatine, and lactate were measured. After the death of the patients, histopathologic changes were determined at autopsy of the brain and were matched voxel‐by‐voxel with the neurometabolites.

Results

The mean ± SD absolute concentrations of NAA (9.15 ± 1.78 mM in patients versus 12.2 ± 0.8 mM in controls; P < 0.01) and creatine (6.43 ± 0.16 mM in patients versus 6.90 ± 0.60 mM in controls; P < 0.003) were significantly reduced and the concentration of choline (2.51 ± 0.42 mM in patients versus 1.92 ± 0.32 mM in controls; P < 0.04) was significantly elevated in NPSLE patients as compared with controls. Widespread heterogeneous changes in the histologic features of the brain were present, including microinfarcts, microhemorrhages, bland angiopathy, thrombotic angiopathy with platelet and fibrin thrombi, neuronal necrosis in various states of resolution, reduced numbers of axons and neurons, vacuole and space formation among the fibers, reduced numbers of oligodendrocytes, reactive microglia and astrocytes, lipid‐laden macrophages, and cyst formation. Neurometabolite abnormalities were closely associated with underlying histopathologic changes in the brain: 1) elevated choline levels were independently associated with gliosis, vasculopathy, and edema (r = 0.75, P < 0.004 in the multivariate model); 2) reduced creatine levels with reduced neuronal–axonal density and gliosis (r = 0.72, P < 0.002 in the multivariate model); 3) reduced NAA levels with reduced neuronal–axonal density (r = 0.66, P < 0.001 in the multivariate model); and 4) the presence of lactate with necrosis, microhemorrhages, and edema (r = 0.996, P < 0.0001 in the multivariate model).

Conclusion

Altered neurometabolites in NPSLE patients, as determined by MRS, are a grave prognostic sign, indicating serious underlying histologic brain injury.
Tetracycline‐regulated bone morphogenetic protein 2 gene expression in lentivirally transduced primary rabbit chondrocytes for treatment of cartilage defects
Authors: Wübbenhorst Daniela , Dumler Katja , Wagner Bettina , Wexel Gabriele , Imhoff Andreas , Gansbacher Bernd , Vogt Stephan , Anton Martina
Published: March 2010

Objective

Treatment of cartilage defects is still challenging, primarily because of the poor self‐healing capacity of articular cartilage. Gene therapy approaches have gained considerable attention, but, depending on the vector system used, they can lead to either limited or unrestrained gene expression, and therefore regulation of gene expression is necessary. This study was undertaken to construct an efficient tetracycline (Tet)–regulated, lentivirally mediated system for the expression of growth factor bone morphogenetic protein 2 (BMP‐2) in primary rabbit chondrocytes that will allow for the induction and termination of growth factor gene expression once cartilage regeneration is complete.

Methods

Chondrogenic ATDC5 cells and primary rabbit chondrocytes were lentivirally transduced with different tetracycline‐on (Tet‐On)–regulated, self‐inactivating vectors for the induction of expression of enhanced green fluorescent protein (eGFP) or BMP‐2, using either a 1‐vector system or a 2‐vector system.

Results

Expression of eGFP was induced on ATDC5 cells and chondrocytes. The highest induction rate and highest level of gene expression were reached when the spleen focus‐forming virus long terminal repeat promoter was used to drive the reverse transactivator expression, after the addition of doxycycline, in chondrocytes. An up to 20‐fold induction of Tet‐mediated BMP‐2 expression was observed on ATDC5 cells. The extent of induction and expression level of BMP‐2 in chondrocytes were similar between the 1‐vector system– and 2‐vector system–infected cells (mean ± SD 15.5 ± 1.1 ng/ml and 14.6 ± 0.4 ng/ml, respectively). In addition, prolonged induction and switching‐off of BMP‐2 expression, as well as repeated induction, were demonstrated. Production of proteoglycans, as shown by Alcian blue staining, demonstrated the functionality of the lentivirally expressed BMP‐2 under induced conditions.

Conclusion

The lentivirally mediated Tet‐On system is an effective strategy for efficient, repeatedly inducible expression of BMP‐2 in primary rabbit chondrocytes. Therefore, use of this system in in vivo experiments may be a promising approach as a treatment strategy for cartilage defects.
Dihydrosphingosine 1‐phosphate has a potent antifibrotic effect in scleroderma fibroblasts via normalization of phosphatase and tensin homolog levels
Authors: Bu Shizhong , Asano Yoshihide , Bujor Andreea , Highland Kristin , Hant Faye , Trojanowska Maria
Published: March 2010

Objective

Previous studies have revealed a phosphatase and tensin homolog (PTEN)–dependent interaction between the sphingolipid agonist dihydrosphingosine 1‐phosphate (dhS1P) and the transforming growth factor β/Smad3 signaling pathway. This study was undertaken to examine responses of systemic sclerosis (SSc) fibroblasts to sphingosine 1‐phosphate (S1P) and dhS1P and to gain further insight into the regulation of the S1P/dhS1P/PTEN pathway in SSc fibrosis.

Methods

Fibroblast cultures were established from skin biopsy samples obtained from patients with SSc and matched healthy controls. Western blotting and quantitative polymerase chain reaction were used to measure protein and messenger RNA levels, respectively. PTEN protein was examined in skin biopsy samples by immunohistochemistry.

Results

PTEN protein levels were low in SSc fibroblasts and correlated with elevated levels of collagen and phospho‐Smad3 and reduced levels of matrix metalloproteinase 1 (MMP‐1). Treatment with dhS1P restored PTEN levels and normalized collagen and MMP‐1 expression, as well as Smad3 phosphorylation status in SSc fibroblasts. S1P was strongly profibrotic in SSc and control fibroblasts. Distribution of S1P receptor isoforms was altered in SSc fibroblasts, which had reduced levels of S1P receptor 1 and S1P receptor 2 and elevated levels of S1P receptor 3. Only depletion of S1P receptor 1 abrogated the effects of dhS1P and S1P in control dermal fibroblasts. In contrast, depletion of either S1P receptor 1 or S1P receptor 2 prevented the effects of S1P and dhS1P in SSc fibroblasts.

Conclusion

Our findings demonstrate that PTEN deficiency is a critical determinant of the profibrotic phenotype of SSc fibroblasts. The antifibrotic effect of dhS1P is mediated through normalization of PTEN expression, suggesting that dhS1P or its derivatives may be effective as therapeutic antifibrotic agents. The distribution and function of S1P receptors differ in SSc and healthy fibroblasts, suggesting that alteration in the sphingolipid signaling pathway may contribute to SSc fibrosis.
Expression of toll‐like receptor 3 and toll‐like receptor 7 in muscle is characteristic of inflammatory myopathy and is differentially regulated by Th1 and Th17 cytokines
Authors: Tournadre A. , Lenief V. , Miossec P.
Published: March 2010

Objective

To assess the expression of Toll‐like receptor 3 (TLR‐3) and TLR‐7 in muscle tissue from patients with polymyositis (PM) and dermatomyositis (DM) and to investigate the function and regulation of TLR‐3 in cultured muscle cells.

Methods

The expression of TLR‐3, TLR‐7, HLA class I, and CD56, a marker of immature myoblast precursors, was analyzed using immunohistochemistry. TLR‐3 regulation and signaling were assessed in myoblasts and in differentiated myotubes with the TLR‐3 agonist poly(I‐C), necrotic myoblasts, and Th1 and Th17 cytokines, in the presence or absence of neutralizing anti–TLR‐3 antibody. Levels of TLR‐3 messenger RNA (mRNA) were quantified by reverse transcription–polymerase chain reaction. Levels of interleukin‐6 (IL‐6), CCL20, and IL‐8 were determined by enzyme‐linked immunosorbent assay.

Results

TLR‐3 and TLR‐7 were expressed in PM/DM tissues, but not in noninflammatory muscle tissues, and were primarily detected in inflammatory infiltrates, although a few muscle cells were also positive. These TLR‐3– and TLR‐7–positive fibers expressed high levels of CD56 and HLA class I antigens. A synergy between poly(I‐C) and IL‐17 was observed for the production of IL‐6 and CCL20. Similarly, stimulation with necrotic myoblasts increased IL‐6 production, and stimulation with necrotic myoblasts in combination with IL‐17 further increased the induction of IL‐6. TLR‐3 blockade decreased the inducing effect of necrotic myoblasts and IL‐17 on IL‐6 production. Stimulation with interferon‐γ (IFNγ) increased TLR‐3 mRNA levels, but IL‐17 down‐regulated the inducing effect of IFNγ.

Conclusion

Our findings indicate that TLR‐3 and TLR‐7 are expressed in inflammatory myopathic tissues, particularly in immature myoblast precursors. Necrotic muscle cells activate cytokine production, in part, through the TLR‐3 pathway, with a differential regulatory effect of Th1 and Th17 cytokines.
Copulæ: Some mathematical aspects
Authors: Sempi Carlo
Published: March 2010

This paper starts with a few critical considerations about the use of copulas in applications, mainly in the field of Mathematical Finance. Two points will be stressed: (i) the construction of asymmetric copulas and (ii) the construction of multivariate copulas. Also, it briefly touches on the long‐standing problem of compatibility. Copyright © 2010 John Wiley & Sons, Ltd.