bluuebunny/crossref_metadata_2025 huggingface dataset:
Integrating Reform‐Oriented Math Instruction in Special Education Settings
Authors: Bottge Brian A. , Rueda Enrique , LaRoque Perry T. , Serlin Ronald C. , Kwon Jungmin
Published: May 2007

This mixed‐methods study assessed the effects of Enhanced Anchored Instruction (EAI) on the math performance of adolescents with learning disabilities in math (MLD). A quasi‐experimental pretest–posttest control group design with switching replications was used to measure students' computation and problem‐solving skills on EAI compared to control conditions. Scores on the curriculum‐aligned and standardized measures showed improved problem‐solving skills but results were mixed for computation. To augment the numerical data, a qualitative inquiry captured day‐to‐day classroom activities. The findings showed that problem‐based curricula such as EAI have the potential for helping students with MLD develop deeper understandings of math concepts but that considerable effort is required to structure and teach these concepts in ways students with MLD understand.
Graphic Organizers Applied to Secondary Algebra Instruction for Students with Learning Disorders
Authors: Ives Bob
Published: May 2007

Students who have particular difficulty in mathematics are a growing concern for educators. Graphic organizers have been shown to improve reading comprehension and may be applied to upper level secondary mathematics content. In two systematic replications, one randomly assigned group was taught to solve systems of linear equations through direct instruction and strategy instruction. The other group was taught with the same methods with the addition of a graphic organizer. Students who received instruction with the graphic organizers outperformed those who received instruction without the organizers. They also better understood the related concepts as measured by immediate posttests in both replications. The difference in understanding concepts was maintained on a 2–3 week posttest.
Griscelli Syndrome
Authors: Emanuel Patrick O. , Sternberg Lauren J. , Phelps Robert G.
Published: May 2007

The dermatology staff was called to evaluate abnormal hair on a 22‐month‐old Hispanic girl whose parents were first cousins. Her medical history was significant for leptomeningitis with subsequent neurologic devastation, gastroesophageal reflux disease, and recurrent respiratory infections. Her hospital course was complicated by sepsis, liver dysfunction, pan‐cytopenia, and disseminated intravascular coagulation. She had developed normally for the first year of life. At 13 months she became progressively lethargic and developed floppy muscle tone; a delay in mental and motor milestones was recognized. Results of a metabolic workup were negative. On examination she was noted to have generalized excessively fair skin when compared with her parents. She had silver‐gray hair (Figure 1) and white eyebrows and body hair. Her maternal grandfather and granduncles had silver hair since childhood, but were without health problems. A maternal family member was said to have light skin. The presumed diagnosis before pathologic examination was Chediak‐Higashi syndrome. Hematoxylin and eosin stain tests revealed prominent melanocytes in the basal layer of the epidermis. The melanocytes were large and distended with a large volume of melanin (Figure 2). The adjacent keratinocytes were completely devoid of melanin. Application of Masson‐Fontana ammoniac silver stain highlighted prominent melanocytic melanin and a relative paucity of melanin in the adjacent keratinocytes (Figure 3). Microscopic examination of her hair revealed clumps of melanin of various sizes and shapes irregularly distributed throughout the hair shaft. Ultrastructural examination of the epidermis showed the melanocytes were distended by an accumulation of large stage IV mature melanosomes. Peripheral blood smear failed to show abnormal granules, even after repeated examination. Based on the clinical features and the pathologic findings, a diagnosis of Griscelli syndrome type 2 was made.

The patient had generalized excessively fair skin when compared with her parents. She had silver‐gray hair and white eyebrows and body hair.

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Microscopic examination of the patient's hair revealed clumps of melanin of various sizes and shapes irregularly distributed throughout the hair shaft.

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Hematoxylin and eosin stain tests (original magnification ×40) revealed prominent melanocytes in the basal layer of the epidermis. The melanocytes were large and distended with a large volume of melanin, while the adjacent keratinocytes had very little melanin.

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Practicing Evidence‐Based Dermatology: A Short Guide
Authors: Barzilai David A. , Weinstock Martin A. , Mostow Eliot N.
Published: May 2007

Evidence‐based medicine (EBM) is a paradigm for systematically collecting, evaluating, and applying the best information currently available to improve patient outcomes. Effective evidence‐based practice requires defining an answerable, well‐built question, systematically searching for the best current evidence, and appraising that evidence for validity. Essential components of EBM also require using our clinical expertise to integrate these data with our patients' characteristics, values, and circumstances; archiving the results of our EBM search; and evaluating the efficiency and effectiveness of the EBM process. Incorporating EBM to bring the best current evidence into our field can be mastered with practice and a commitment to apply the process daily.
On the Cytology of Toxoglugea chironomi (Debaisieux, 1931) Jírovec 1936 (Microspora, Thelohaniidae)
Authors: BYLÉN EVA K. C. , LARSSON J. I. RONNY
Published: May 2007

ABSTRACT. The light microscopic and ultrastructural characteristics of a microsporidium provisionally identified as Toxoglugea chironomi (Debaiseux, 1931) Jírovec, 1936, is described. It was isolated from oenocytes and adipose tissue of a midge larva of the genus Dicrotendipes. Merozoites are diplokaryotic. The sporogony produces, by fragmentation, eight monokaryotic spores in a sporophorous vesicle. Mature spores are horse‐shoe shaped. The total length is about 5.8 μm, the width 0.8‐0.9 μm, the external height of the curve 2.3‐3.5 μm, and the external width of the curve 3.5‐5.2 μm. The polaroplast has lamellar compartments of two types: narrow and closely packed anteriorly, and wider and more loosely arranged posteriorly. The isofilar polar filament is arranged in 8–10 coils in the posterior fourth of the spore. The external nuclear membrane is sometimes continuous with the endoplasmic reticulum. Lamellar and tubular material of exospore construction are present in the episporontal space from the beginning of sporogony. Teratological and normal spores sometimes occur together in the sporophorous vesicle. The identification of the species is discussed and the ultrastructure is compared to Toxoglugea variabilis, the only further species of the genus with known ultrastructural cytology.
Kinetics of Expression of Two Major Plasmodium berghei Antigens in the Mosquito Vector, Anopheles stephensi
Authors: SIMONETTI AMAURI B. , BILLINGSLEY PETER F. , WINGER LARRY A. , SINDEN ROBERT E.
Published: May 2007

ABSTRACT. Expression of a 21 kDa determinant (Pbs21), first detected on the surface of ookinetes, and of the circumsporozoite protein (CSP) was studied by immunofluorescence and Western blots during the developmental cycle of Plasmodium berghei in the mosquito A nopheles stephensi. The expression of Pbs21 was predominantly localised on the ookinete surface one day after the infectious blood meal, and thereafter reactivity declined to a minimum on days 2 and 3, the time of onset of oocyst development. A gradual increase in fluorescence was observed on the oocysts from day 6 that was retained until day 17 post‐infection. In contrast, sporozoites released from oocysts or salivary glands showed little or no antibody labelling with anti‐Pbs21. Circumsporozoite protein was not detectable in any rnidgut preparations until 5–6 days after feeding, when reactivity was observed against immature oocysts. Expression then continued and increased throughout oocyst and sporozoite development. Western blots confirmed that Pbs21 was expressed minimally during the oocyst development but was not detectable in sporozoites. Co‐localisation of anti‐Pbs21 and anti‐CSP monoclonal antibodies to the 50 kDa and 60 kDa bands in Western blots of sporozoite suggests immunological cross‐reactivity between the CSP and the anti‐21 kDa antibodies.
Amylopectin Synthase of Eimeria tenella: Identification and Kinetic Characterization
Authors: KARKHANIS YASHWANT D. , ALLOCCO JOHN J. , SCHMATZ DENNIS M.
Published: May 2007

ABSTRACT. A soluble enzyme amylopectin synthase (UDP‐glucose‐α 1,4‐glucan α‐4‐glucosyltransferase) which transfers glucose from uridine 5′‐diphosphate glucose (UDP‐glucose) to a primer to form α‐I,4‐glucosyl linkages has been identified in the extracts of unsporulated oocysts of Eimeria tenella. UDP‐glucose and not ADP‐glucose was the most active glucosyl donor. Corn amylopectin, rabbit liver glycogen, oyster glycogen and corn starch served as primers; the latter two were less efficient. The enzyme has an apparent pH optimum of 7.5 and exhibited typical Michaelis‐Menten kinetics with dependence on both the primer and substrate concentrations. The Michaelis constants (Km). with respect to UDP‐glucose, was 0.5 mM; and 0.25 mg/ml and 1.25 mg/ml with respect to amylopectin and rabbit liver glycogen. The product formed by the reaction was predominantly a glucan containing α‐1,4 linkages. The specificity of the enzyme suggests that this enzyme is similar to glycogen synthase in eukaryotes and has been designated as amylopectin synthase (UDP‐glucose‐α‐1,4‐glucosetransferase EC 2.4.1.11).
Ultrastructure of Ditrichomonas honigbergii N. G., N. Sp. (Parabasalia) and Its Relationship to Amitochondrial Protists
Authors: FARMER MARK A.
Published: May 2007

ABSTRACT. Ditrichomonas honigbergii n. g., n. sp. is a small trichomonad flagellate that has three emergent flagella arising from four basal bodies, a parabasal apparatus (single dictyosome with associated striated flagellar rootlets), a microtubular axostyle, a short undulating membrane, and hydrogenosomes. Cultures of D. honigbergii were isolated from the sediments of a freshwater lake and there is no known metazoan host. Cells form walled cysts with internalized flagella and go through all phases of the life cycle (excystment, binary division, encystment) without any perturbations to the culture medium. Ditrichornonas honigbergii is capable of ingesting and digesting bacteria by phagocytosis. These facts suggest that D. honigbergii may be a free‐living inhabitant of oxygen‐reduced environments. The structure of D. honigbergii is similar to that of retortamonads and the relationship of trichomonads to other amitochondrial protists is discussed.
Purine Nucleoside and Nucleobase Cell Membrane Transport in Giardia lamblia
Authors: BAUM KENNETH F. , BERENS RANDOLPH L. , MARR J. JOSEPH
Published: May 2007

ABSTRACT. Giardia lamblia is dependent on the salvage of preformed purines and pyrimidines. This study investigated purine nucleoside and nucleobase transport utilizing rapid uptake determinations. Nucleoside substrate/velocity curves exhibited the hyperbolic kinetics of a saturable carrier‐mediated system. Deoxynucleosides exhibited a much lower affinity for the transporter. Inhibition studies confirmed the relative camer affinities of these ribonucleosides and deoxyribonucleosides. The nucleobase adenine did not exhibit saturation lunetics at a comparable substrate range, and did not inhibit nucleoside transport. Dipyridamole markedly inhibited nucleoside but not nucleobase transport, confirming the separate entry pathways. When cells were depleted of ATP, the velocity of nucleoside and nucleobase transport was unchanged, indicating that it is a non‐energy‐dependent process. Three nucleoside analogs, formycin A, adenine arabinoside and 7–deazaadenosine, were studied. Transport kinetics ranged widely among this group and could not completely account for their cytotoxic effect. When the apparent Km and Vmax of the nucleosides were compared, an approximately linear relationship (r2= 0.95) was noted. This suggests that a high affinity of the nucleoside permease for the substrate retards disassociation of the substrate‐carrier complex, slowing net influx.
Biochemical Analysis of a Mutant Tetrahymena Lacking Outer Dynein Arms
Authors: LUDMANN SUSAN A. , SCHWANDT ANITA , KONC XUEJUN , BRICKER CONNIE S. , PENNOCK DAVID G.
Published: May 2007

ABSTRACT. Tetrahymena thermophila mutants homozygous for the oad mutation become nonmotile when grown at the restrictive temperature, and axonemes isolated from nonmotile mutants lack approximately 90% of their outer dynein arms. Electrophoretic analyses of axonemes isolated from nonmotile mutants (oad axonemes) indicate they contain significantly fewer of the 22 S dynein heavy chains that axonemes isolated from wild‐type cells (wild‐type axonemes) contain. The 22 S dynein heavy chains that remain in axonemes isolated from nonmotile, oad mutants are assembled into 22 S dynein particles that exhibit wild‐type levels of ATPase activity. Two‐dimensional gel electrophoresis of oad axonemes show that they are deficient in no proteins other than those proteins thought to be components of 22 S dynein. This report is the first formal proof that outer dynein arms in Tetrahymena cilia are composed of 22 S dynein.
The dcc Mutation Affects Ciliary Length in Tetrahymena thermophila
Authors: GITZ DARRELL L. , EELLS JEFFREY B. , PENNOCK DAVID G.
Published: May 2007

ABSTRACT. We have characterized ciliogenesis in a mutant Tetrahymena thermophila that both fails to regain motility following deciliation and that fails to complete cytokinesis. Scanning electron microscopic (SEM) observations revealed that starved deciliated cells regenerated fewer, shorter cilia at the restrictive temperature than similarly treated cells incubated at the permissive temperature. Transmission electron microscopic evaluation of isolated, regenerated cilia revealed no structural abnormalities. Incorporation of S‐35 methionine was similar during ciliary regeneration at both the restrictive and permissive temperatures, indicating the mutant phenotype was not due to a simple failure in translation or transcription. Mutant cells incubated in growth medium at the restrictive temperature arrested in cytokinesis and assembled a large number of abnormally short cilia. These cells also developed irregular surface projections that were not visible on wild‐type cells. These observations suggest that ciliogenesis can be initiated in growing cells as well as in starved deciliated cells but that elongation is inhibited before cilia reach full length. The mutation was named dcc for defective in ciliogenesis and cytokinesis.
Modulation of Complement Resistance and Virulence of Naegleria fowleri Amoebae by Alterations in Growth Media
Authors: TONEY DENISE M. , MARCIANO‐CABRAL FRANCINE
Published: May 2007

ABSTRACT. Highly‐pathogenic, mouse‐passaged Naegleria fowleri amoebae are complement resistant. The present study evaluates the effect of complement on N. fowleri and the virulence of the amoebae after animal passage and growth in two different axenic media. Pathogenic N. fowleri maintained in “enriched” Cline medium are virulent for mice and resistant to complement lysis. A rapid decline in resistance to complement and virulence for mice is observed when highly‐pathogenic N. fowleri are grown in Nelson medium lacking hemin. N. fowleri maintained in Nelson medium can be rendered complement‐resistant by shifting the amoebae to growth in Cline medium for 2 h prior to the addition of complement. Cycloheximide treatment of N. fowleri maintained in Nelson medium blocks the transition to a complement‐resistant phenotype following a shift in growth medium. Proteins were radiolabeled with [35S] during a shift from Nelson to Cline medium to identify specific polypeptides which may be associated with the functional activities related to virulence and resistance to complement.
New Species of Lagenophrys (Ciliophora, Peritrichia) from New Zealand and Australia1
Authors: CLAMP JOHN C.
Published: May 2007

Lagenophrys novazealandae n. sp. occurs on the gills of Paranephrops zealandicus, a parastacid crayfish from New Zealand. The new species has the hemispheroidal lorica most common among members of its genus and is distinguished by its possession of large tubercles on the thickened edge of the anterior lip of the lorica aperture, a deep cleft in the left side of the lip's edge, and a ovoid to reniform macronucleus located in the right‐hand part of the body. It is probable that an as yet unnamed species of Lagenophrys known to occur on another species of Paranephrops in New Zealand is distinct from L. novazealandae but phylogenetically related to it. Lagenophrys petila n. sp. occurs on setae of Parastacoides tasmanicus, a parastacid from Tasmania. The new species has an ovoid lorica tapering to a slender pseudostalk at the posterior end, a type of lorica possessed by only two other members of its genus that also attach to their host's setae. It is distinguished from the other ovoid species by the proportions of the lorica, the extreme shortness of the lips of the lorica aperture, and an ovoid macronucleus located in the right, anterior part of the body. Clefts in the lips of L. novazealandae and other members of Lagenophrys may function as points of flexure to allow the lips to bend in ways that accommodate interspecific differences in the size of the epistomial disk and its operation during suspension feeding.
Trichomonas vaginalis: Dominant G2 Period and G2 Phase Arrest in a Representative of an Early Branching Eukaryotic Lineage
Authors: RILEY DONALD E. , KRIEGER JOHN N. , MINER DAVID , RABINOVITCH PETER S.
Published: May 2007

ABSTRACT. Eukaryotic mitotic cell cycles have been extensively studied in yeasts and vertebrate cells but little is known about cell cycle mechanisms in early branches of the eukaryotic lineage. Trichomonas vaginalis represents one of the earliest branching eukaryotic lineages available for study. In contrast with most yeasts and vertebrate cells, the T. vaginalis G2 period was prolonged, comprising 50 to 58% of the cell population. Hydroxyurea, aphidicolin, and excess thymidine, all of which arrest yeasts and vertebrate cells at the G1/S phase boundary, had no effect on the T. vaginalis cell cycle, probably due to the known absence of synthetic pathways. The antimicrotubule mitotic inhibitors, colchicine and nocodazole, induced G2 phase synchrony. Metronidazole, a therapeutic reagent, also caused G2 phase arrest. These observations suggest that T. vaginalis is similar to yeasts and vertebrate cells in G2 and M phases, but the parasite's G1/S phase transition is distinctive. The results also suggest potentially therapeutic, anti‐trichomonad activity of microtubule inhibitors such as nocodazole. The cultured parasite may prove useful as a model for the mitotic cell cycle in the absence of G1/S phase transitional activities universal in yeasts and vertebrate cells.
Identification of the Tubulin Gene Family and Sequence Determination of One β‐Tubulin Gene in a Cold‐Poikilotherm Protozoan, the Antarctic Ciliate Euplotes focardii
Authors: MICELI CRISTINA , BALLARINI PATRIZIA , DI GIUSEPPE GRAZIANO , VALBONESI ALESSANDRO , LUPORINI PIERANGELO
Published: May 2007

ABSTRACT. Four different tubulin genes were identified in the somatic nucleus (macronucleus) of Euplotes focardii, a strictly coldadapted, Antarctic ciliate: one of 1,800 bp for α‐tubulin and three of 2,150, 1,900, and 1,600 bp, respectively, for β‐tubulin. Preliminarily analysed for restriction fragment length polymorphisms, these genes showed remarkable differences in organisation from tubulin genes of other ciliates which live in temperate areas and were analysed in parallel with E. focardii. The complete coding sequence of the 1,600 bp β‐tubulin gene was then determined and shown to contain unique structural features of potential importance for E. focardii microtubule organization and activity. Of eight unique substitutions detected, seven were concentrated in the large amino terminal domain of the molecule that directly interacts with the carboxy terminal region of α‐tubulin for heterodimer formation. Sequence analysis of the cloned gene revealed, in addition, a potential new exception in the use of the genetic code by ciliates. A TAG codon was aligned in correspondence with Trp‐21 which is strictly conserved in every tubulin sequence so far determined.
Synthesis and Characterization of Bismuth Titanate by an Aqueous Sol–Gel Method
Authors: Du Xianfeng , Xu Youlong , Ma Hanxiao , Wang Jie , Li Xifei
Published: May 2007

A highly stable, reproducible and water‐based bismuth titanate (BTO) sol system has been synthesized by an aqueous sol–gel method. First bismuth nitrate was dissolved in acetic acid, and then it was mixed with a solution of lactic acid dissolved tetra‐n‐butyl titanate, subsequently, water was added to adjust sol concentration. As‐obtained sols or gels were characterized by Ultraviolet–Visible Spectrophotometer, derivative differential thermal analysis‐differential thermal analysis–thermal gravimetry,in situRaman, and high‐temperature X‐ray diffraction. Results show that the BTO sol can remain stable for more than 1 year and BTO can start to crystallize at about 450°C.
Influence of CeO2 Reduction on the Microstructure and Mechanical Properties of Pulsed Electric Current Sintered Y2O3–CeO2 Co‐Stabilized ZrO2 Ceramics
Authors: Huang S. G. , Vanmeensel K. , Biest O. Van der , Vleugels J.
Published: May 2007

The combination of yttria co‐stabilization and pulsed electric current sintering allowed full densification of CeO2‐containing ZrO2 ceramics in a graphite environment, while avoiding spontaneous catastrophic material degradation due to ceria reduction. Tetragonal ZrO2 ceramics were obtained by pulsed electric current sintering (PECS) of 1 mol% Y2O3+6 mol% CeO2 (1Y6Ce) stabilizer‐coated monoclinic ZrO2 powder with 2 wt% Al2O3 as sintering additive for 2 min at 1450° or 1550°C under a maximum pressure of 60 MPa. In addition, a 2 mol% Y2O3 doped ZrO2 (2Y) ceramic was used as reference material to elucidate the effect of CeO2 reduction in the densified 1Y6Ce ceramics. The influence of the CeO2 reduction and sintering temperature on the microstructure and mechanical properties of the co‐stabilized ZrO2 ceramics was investigated. A graded microstructure with a gradient in color and mechanical properties were observed in the 1Y6Ce ceramic sintered at 1450°C, whereas the 1Y6Ce ZrO2 sintered at 1550°C and the 2Y ceramic had a uniform color and mechanical properties. Additionally, the formation of an elongated CeAl11O18 (Ce2O3·11Al2O3) phase was observed in the 1Y6Ce ceramic sintered at 1550°C. The formation of the graded color, the presence of the CeAl11O18 phase, as well as the graded fracture toughness profile were explained in terms of the gradual reduction of CeO2 to Ce2O3 in the 1Y6Ce ceramic.
Structural Level of Silica‐Fumed Aqueous Suspensions
Authors: Galindo‐Rosales F. J. , Rubio‐Hernández F. J. , Velázquez‐Navarro J. F. , Gómez‐Merino A. I.
Published: May 2007

The static and dynamic yield stresses have been obtained for two different silica‐fumed aqueous suspensions (2.5% and 7.5% v/v). An experimental method proposed by Cheng [D.C‐H. Cheng, Rheol. Acta, 25, (1986), 542–554] for thixotropic systems has been used to obtain the dynamic yield stress. To get the static yield stress a shear stress ramp has been applied. Analysis of the results let us conclude that we can compare the structural level reached for different thixotropic suspensions that have undergone the same shear load.
Optimization of the Bend Strength of Flat‐Layered Alumina−Zirconia Composites
Authors: Ambrožič Milan , Kosmač Tomaž
Published: May 2007

We have made a theoretical study of the bend strength of flat, multilayered alumina−zirconia composites. We used the linear theory of elasticity to calculate the stresses in materials subjected to a three‐point bending test, including the thermal residual stresses that result from the fabrication process. We studied symmetrically and non‐symmetrically layered composites with a variable number of layers, with the focus on the optimization of individual layer thicknesses to get the highest composite strength. Using typical strength data for particulate composites from the literature, we found that it is sensible to optimize the composite with up to seven layers as taking even more layers does not further improve the composite strength significantly. Furthermore, there is a qualitative difference in the total stress distribution through the sample thickness in the case of optimized and non‐optimized structure, respectively.
Layer Structure of Textured CaBi4Ti4O15Ceramics Fabricated by Slip Casting in High Magnetic Field
Authors: Kimura Masahiko , Shiratsuyu Kosuke , Ando Akira , Suzuki Tohru S. , Sakka Yoshio
Published: May 2007

Textured CaBi4Ti4O15(CBT) ceramics were fabricated by slip casting in a high magnetic field of 12 T, and a layer structure was obtained by co‐firing with the textured CBT ceramics and a metal internal electrode. The crystallinea(b)‐axis of CBT was aligned parallel to the magnetic field, and highlya(b)‐axis textured ceramics were obtained. The orientation degree of the textured ceramics was 0.82, and the electromechanical coupling coefficient of thickness extensional (TE) vibration was about 1.5 times larger than that of the randomly oriented ceramics. The second harmonic TE vibration was successfully generated in the layer structure specimens, which contained two layers of the textured ceramics and an internal electrode. Therefore, it was recognized that the layer structure was satisfactorily fabricated.
Grain‐Boundary Diffusion of Cr in Pure and Y‐Doped Alumina
Authors: Bedu‐Amissah K. , Rickman J. M. , Chan H. M. , Harmer M. P.
Published: May 2007

The diffusive transport of chromium in both pure and Y‐doped fine‐grained alumina has been investigated over the temperature range 1250°–1650°C. From a quantitative assessment of the chromium diffusion profile in alumina, as obtained from electron microprobe analysis, it was found that yttrium doping retards cation diffusion in the grain‐boundary regime by over an order of magnitude. The Arrhenius equations for the undoped and Y‐doped samples were determined to be: δDb=(4.77±0.24) × 10−7 exp (−264.78±47.68 (kJ/mol)/RT)(cm3/s) and δDb=(6.87±0.18) × 10−8 exp (−284.91±42.57 (kJ/mol)/RT)(cm3/s), respectively. Finally, to elucidate the mechanism for this retardation, the impact of yttrium doping on diffusion activation energies and prefactors was examined.
COMMENTARY
Authors: Holmgren Jan , Nilsson Lars‐Åke
Published: May 2007

Örjan Ouchterlony became famous all over the scientific world because of the immunodiffusion‐in‐gel technique that he developed in the 1940s. At one time he was the most cited author in the scientific literature for all categories (at present around 11,000 citations) and it is noteworthy that three of his early and epoch‐making publications were published in Acta pathologica et microbiologica scandinavica. As a matter of curiosity it may be mentioned that his first and the most fundamental publication was originally sent to a well‐recognized international journal but was rejected based on the referee's opinion that the observations described most likely were either due to an artifact or represented an epiphenomenon of little or no medical interest.
Fish assemblages and seasonal movements of fish in irrigation canals and river reaches of the middle Rio Grande, New Mexico (USA)
Authors: Cowley D. E. , Wissmar R. C. , Sallenave R.
Published: May 2007

Abstract – Synoptic fish surveys of river and irrigation canal sites and a path‐analytic approach evaluate seasonal changes in fish assemblages in canal systems and river reaches of the middle Rio Grande, NM (USA). The objective was to assess how fish assemblages within the Isleta Reach respond to irrigation season and off‐season variations in water and fish contributions from upstream river channels (Albuquerque Reach) and from the Peralta irrigation system. Eighteen species of fish were found in the irrigation canals, 13 in the Isleta Reach and 15 in the Albuquerque Reach. The proportion of nonnative fishes was higher in canals (56%) than in the river (11%). Species rank abundances were used in path analyses of fish species compositions during the irrigation season and off‐season. During the irrigation season, path coefficients indicated fish movements downstream from the Albuquerque Reach (0.55) to the Isleta Reach exceeded contributions by the conveyance‐return (0.29) and drain‐return (0.05) canals. However, as the river de‐watered the return canals were important refuge habitats for native fishes. The 0.05 value represented a major decline relative to the path coefficient for the upstream Peralta drain canal (0.72). During the off‐season path coefficients indicated fish movements of 0.47 downstream in the river and 0.59 in the conveyance‐return canal but a negligible value for the drain‐return canal (‐0.06). Irrigation management could be modified to favour native fish ecology by controlling movement of nonnative predators in canal systems and in providing refuge habitats for native fish during periods when water demand exceeds the supply.
Development of the pons in human fetuses
Authors: Hatta Toshihisa , Satow Fumio , Hatta Junko , Hashimoto Ryuju , Udagawa Jun , Matsumoto Akihiro , Otani Hiroki
Published: May 2007

ABSTRACT  Morphometric and histological studies of the pons were performed by light microscopy in 28 cases of externally normal human fetuses ranging from 90 to 246 mm in crown‐rump length (CRL) and from 13 to 28 weeks of gestation. The brainstems of fetuses were embedded in celloidin or paraffin, and transverse sections were prepared. The pons was divided into two regions at the most ventral margin of the medial lemniscus at the level of the motor trigeminal nucleus. The relationships between the total dorsoventral length, ventral length, and dorsal length of the pons versus CRL and gestational ages were calculated, and empiric formulas were fitted. It was found that the ventral portion increased in size more rapidly than the dorsal portion. The proportion of the ventral portion in the total dorsoventral length was constitutively higher than that of the dorsal portion in the present range of CRL. In the pontine nuclei, from 235 mm in the CRL, some large cells with rich cytoplasm, pale nuclei, and a distinct nucleolus appeared on the dorsal side of the pyramidal tract. According to Weigert stained preparations, the first myelinated fibers in each motor root of the trigeminal, abducent, and facial nerves were recognized at 130–140 mm in CRL and the medial lemniscus at 230–235 mm.
Cerebro–fronto–facial syndrome (Dandy‐Walker Variant and Frontofacial Dysmorphisms): report of the first case identified by increased nuchal translucency beyond 13+6 weeks
Authors: Tonni Gabriele , Azzoni Daniela , Ambrosetti Fabrizio , De Felice Claudio , Ventura Alessandro
Published: May 2007

ABSTRACT  A 32‐year‐old gravida 2, para 1 woman, with a previous uneventful pregnancy, underwent first trimester ultrasound screening for Down syndrome at 13 weeks according to the Fetal Medicine Foundation guidelines (http://www.fetalmedicine.com/pdf/11‐14/english/FMF‐English.pdf). The ultrasound showed increased nuchal translucency (NT) of 8.9 mm with an estimated risk of Down syndrome of 1:8. Fetal karyotype was normal 46,XX by chorionic villus sampling. The patient underwent weekly ultrasound and at 19 weeks of gestation, a dilatation of the 4th ventricle with partial agenesis of the cerebellar vermis and normal posterior fossa were observed by transvaginal transcerebellar section of the fetal head. This finding was consistent with a diagnosis of Dandy‐Walker variant and the patient opted for termination of pregnancy after extensive counselling. Autoptic examination confirmed the prenatal ultrasonographic findings and revealed signs of an underlying cerebro–fronto–facial syndrome due to the presence of facial dysmorphisms consistent with horizontal eyelid, high nasal root, low set ears and a wide forehead. Increased NT is not only a common phenotypic expression of chromosomal abnormalities, but is also associated with a wide range of fetal defects and genetic syndromes. Careful ultrasonographic follow‐up is mandatory in all cases of increased first trimester nuchal translucency with normal karyotype in order to identify associated anomalies.
Comments from the Developmental Neurotoxicology Committee of the Japanese Teratology Society on the OECD Guideline for the Testing of Chemicals, Proposal for a New Guideline 426, Developmental Neurotoxicity Study, Draft Document (October 2006 version), and on the Draft Document of the Retrospective Performance Assessment of the Draft Test Guideline 426 on Developmental Neurotoxicity
Authors: Ema Makoto , Fukui Yoshihiro , Aoyama Hiroaki , Fujiwara Michio , Fuji Junichiro , Inouye Minoru , Iwase Takayuki , Kihara Takahide , Oi Akihide , Otani Hiroki , Shinomiya Mitsuhiro , Sugioka Kozo , Yamano Tsunekazu , Yamashita Keisuke H. , Tanimura Takashi
Published: May 2007

ABSTRACT  In October 2006, a new revision of the draft guideline (OECD Guideline for the Testing of Chemicals, Proposal for a New Guideline 426. Developmental Neurotoxicity Study) and Draft Document of the Retrospective Performance Assessment (RPA) of the Draft Test Guideline 426 on Developmental Neurotoxicity were distributed following incorporation of the results of the Expert Consultation Meeting in Tokyo on May 24–26, 2005. The draft guideline consists of 50 paragraphs and an appendix with 102 references; and the draft RPA consists of 37 paragraphs with 109 references. National coordinators were requested to arrange for national expert reviews of these draft documents in their member countries. Members of the Developmental Neurotoxicology (DNT) Committee of the Japanese Teratology Society (JTS) reviewed, discussed, and commented on the draft Test Guideline Proposal. The DNT Committee of the JTS also commented on the draft document of the RPA. These comments were sent to the OECD Secretariat. The DNT Committee of the JTS expects the comments to be useful for the finalization of these draft documents.
Effects of P‐Glycoprotein Inhibitor and Elicitor on the Salt Tolerance of Rice Seedlings
Authors: Fang Liang‐Jun , Fu Xiao‐Qin , Ye Qun‐Shan , Wu Tian , Wang Zheng‐Chao , Chen Xiao , Zhu Zhi‐Kai , Zhang Xing‐Fu , Fu Chui‐Kang
Published: May 2007

Hymexazol (3‐Hydroxy‐5‐methylisoxazole) as the main ingredients of HI (elicitor) was used to screen salt‐tolerant species from 122 salt‐tolerant rice (Oryza sativa L.) cultivars under specific inducement. The results showed that the local species R6 is highly induce‐sensitive. R6 showed salt tolerance during the whole growth period by using 1.0% NaCl solution after HI treatment. Cyclosporin A (CsA) and verapamil (VP) as P‐glycoprotein (PGP) inhibitors and rifampin (RFP) as a PGP elicitor were used to treat R6. The morphological traits, structure of the root, physiological characteristics of leaf and root systems, the content of endogenous hormones indole‐3‐acetic acid (IAA) and abscisic acid (ABA) etc. show that CsA, VP and RFP had remarkable effects on the rice's salt tolerance. Hymexazol inducement (HI) can improve the rice's salt tolerance greatly and make it more salt‐resistant.

(Handling editor: Jin‐Zhong Cui)
Aerenchyma Formed Under Phosphorus Deficiency Contributes to the Reduced Root Hydraulic Conductivity in Maize Roots
Authors: Fan Mingshou , Bai Ruiqin , Zhao Xuefeng , Zhang Jianhua
Published: May 2007

Root hydraulic conductivity has been shown to decrease under phosphorus (P) deficiency. This study investigated how the formation of aerenchyma is related to this change. Root anatomy, as well as root hydraulic conductivity was studied in maize (Zea mays L.) roots under different phosphorus nutrition conditions. Plant roots under P stress showed enhanced degradation of cortical cells and the aerenchyma formation was associated with their reduced root hydraulic conductivity, supporting our hypothesis that air spaces that form in the cortex of phosphorus‐stressed roots impede the radial transport of water in a root cylinder. Further evidence came from the variation in aerenchyma formation due to genotypic differences. Five maize inbred lines with different porosity in their root cortex showed a significant negative correlation with their root hydraulic conductivity. Shoot relative water content was also found lower in P‐deficient maize plants than that in P‐sufficient ones when such treatment was prolonged enough, suggesting a limitation of water transport due to lowered root hydraulic conductivity of P‐deficient plants.

(Handling editor: Ming Yuan)
Water and Nutrient Use Efficiency in Diploid, Tetraploid and Hexaploid Wheats
Authors: Huang Ming‐Li , Deng Xi‐Ping , Zhao Yu‐Zong , Zhou Sheng‐Lu , Inanaga Shinobu , Yamada Satoshi , Tanaka Kiyoshi
Published: May 2007

Three diploid (Triticum boeoticum, AA; Aegilops speltoides, BB and Ae. tauschii, DD), two tetraploid (T. dicoccoides, AABB and T. dicoccon, AABB) and one hexaploid (T. vulgare, AABBDD) varieties of wheat, which are very important in the evolution of wheat were chosen in this study. A pot experiment was carried out on the wheat under different water and nutrient conditions (i) to understand the differences in biomass, yield, water use efficiency (WUE), and nutrient (N, P and K) use efficiency (uptake and utilization efficiency) among ploidies in the evolution of wheat; (ii) to clarify the effect of water and nutrient conditions on water and nutrient use efficiency; and (iii) to assess the relationship of water and nutrient use efficiency in the evolution of wheat. Our results showed that from diploid to tetraploid then to hexaploid during the evolution of wheat, both root biomass and above‐ground biomass increased initially and then decreased. Water consumption for transpiration decreased remarkably, correlating with the decline of the growth period, while grain yield, harvest index, WUE, N, P and K uptake efficiency, and N, P and K utilization efficiency increased significantly. Grain yield, harvest index and WUE decreased in the same order: T. vulgare > T. dicoccon > T. dicoccoides > Ae. tauschii > Ae. speltoides > T. boeoticum. Water stress significantly decreased root biomass, above‐ground biomass, yield, and water consumption for transpiration by 47–52%, but remarkably increased WUE. Increasing the nutrient supply increased wheat above‐ground biomass, grain yield, harvest index, water consumption for transpiration and WUE under different water levels, but reduced root biomass under drought conditions. Generally, water stress and low nutrient supply resulted in the lower nutrient uptake efficiency of wheat. However, water and nutrient application had no significant effects on nutrient utilization efficiency, suggesting that wheat nutrient utilization efficiency is mainly controlled by genotypes. Compared to the other two diploid wheats, Ae. squarrosa (DD) had significant higher WUE and nutrient utilization efficiency, indicating that the D genome may carry genes controlling high efficient utilization of water and nutrient. Significant relationships were found between WUE and N, P and K utilization efficiency.

(Handling editor: Jin‐Zhong Cui)
Variations in Growth, Photosynthesis and Defense System Among Four Weed Species Under Increased UV‐B Radiation
Authors: Wang Shiwen , Duan Liusheng , Eneji Anthony Egrinya , Li Zhaohu
Published: May 2007

Weed tolerance of UV‐B radiation varies with species, and the radiation could affect weed ecology and management. Variations in growth, photosynthesis and defense system among four important agronomic weeds, Abutilon theophrasti Medik, Amaranthus retroflexus L., Digitaria sanguinalis (L.) Scop and Chloris virgata Swartz, under increased UV‐B radiation (ambient and increased radiation at 2.7, 5.4 and 10.8 kJ‐m−2‐d−1) were studied in the greenhouse experiment. After 2 weeks of radiation, the shoots’dry mass decreased with increasing UV‐B radiation except for D. sanguinalis. The reduction in biomass was the result of changes in morphology and physiology. Higher levels of UV‐B treatment decreased the leaf area, plant height, net photosynthetic rate and chlorophyll contents, while it increased the contents of wax and UV‐B absorbing compound in all species, except for A. retroflexus, which did not increase significantly. The activity of superoxide dismutase, catalase, ascorbate peroxide and the content of ascorbic acid changed differently among the weed species as UV‐B radiation increased. D. sanguinalis was the most tolerant and A. retroflexus the most sensitive to increased UV‐B radiation. The results also show that the two grass species (D. sanguinalis and C. virgata) were more tolerant to UV‐B radiation than the two broad‐leafed species (A. theophrasti and A. retroflexus). The UV‐B absorbing compound and leaf wax played important roles against UV‐B damages in the two grass weeds. The overall results suggest that weed community, competition and management will be altered by continuous ozone depletion.

(Handling editor: Li‐Xin Zhang)
Variation of Bioactive Compounds in Hypericum perforatum Growing in Turkey During Its Phenological Cycle
Authors: Cirak Cüneyt , Radusiěnë Jolita , Karabük Birsen (Saglam) , Janulis Valdimaras , Ivanauskas Liudas
Published: May 2007

The present study was conducted to determine phenologic and morphogenetic variation of hypericin, chlorogenic acid and flavonoids, as rutin, hyperoside, apigenin‐7‐O‐glucoside, quercitrin, quercetin content of Hypericum perforatum L. growing in Turkey. Wild growing plants were harvested at vegetative, floral budding, full flowering, fresh fruiting and mature fruiting stages and dissected into stem, leaf and reproductive tissues and assayed for bioactive compounds by the High performance liquid chromatography (HPLC) method. Hypericin concentration ranged between 0 and 2.73 mg/g DW, chlorogenic acid 0.00–3.64 mg/g DW, rutin 0.00–3.36 mg/g DW, hyperoside 0.04–22.42 mg/g DW, quercitrin 0.03–3.45 mg/g DW and quercetin 0.04–1.02 mg/g DW depending on ontogenetic and morphogenetic sampling. Leaves were found to be superior to stems and reproductive parts with regard to phenolic accumulation for all compounds tested while flowers accumulated the highest levels of hypericin. Quercitrin, quercetin and hypericin content in all tissues increased with advancing of developmental stages and reached their highest level during flower ontogenesis. Similarly, chlorogenic acid, hyperoside and apigenin‐7‐O‐glucoside content in different plant parts increased during plant development, however, the highest level was observed at different stages of plant phenology for each tissue. Chlorogenic acid was not detected in stems, leaves and reproductive parts in several stages of plant phenology and its variation during plant growth showed inconsistent manner. In contrast to the other compounds examined, rutin content of stems and leaves decreased with advancing of plant development and the highest level for both tissues was observed at the vegetative stage. However, content of the same compound in reproductive parts was the highest at mature fruiting. The present findings might be useful to obtain increased concentration of these natural compounds.

(Handling editor: Jian‐Min Yue)
USING A MODIFIED MOUSE TO READ DATA FROM NONSTRUCTURED LINE SCALES
Authors: SANCHEZ RICARDO , HOUGH GUILLERMO
Published: May 2007

Nonstructured line scales (NLS) are widely used in sensory and consumer research, normally generating a large amount of data to be introduced to computers for statistical analysis. This process can be very much accelerated with the use of special hardware and software. Available systems are efficient but costly. To overcome this last item a standard mouse was modified to be used as a measuring instrument, and a simple QBASIC program was developed to input the measured data into an ASCII file. The cost of the modified mouse was $60, and data input was 5 times faster than measuring distances with a ruler. Experiments designed to test the mouse showed that error measurements were small.
INFLUENCE OF FOOD MATRIX STRUCTURE AND ORAL BREAKDOWN DURING MASTICATION ON TEMPORAL PERCEPTION OF FLAVOR
Authors: WILSON CLAIRE E. , BROWN WENDY E.
Published: May 2007

Perception of flavor intensity from a series of model foods was recorded during normal mastication by 8 subjects. Samples varied in gelatin concentration (5–25%) and in the sweetener added (sucrose or aspartame) and represented a range of physical and mechanical properties. All contained the same level of a commercial flavor (banana). Mastication patterns were recorded using electromyography simultaneously with sensory assessment. Increasing the mechanical strength and melting point of the samples resulted in longer chewing times and lower intensity and more prolonged flavor perception. The temporal pattern of flavor perception was closely linked with mastication patterns for each subject but exhibited large individual differences. Flavor perception was influenced by the habitual oral breakdown patterns for individuals.
SENSORY DIFFERENCE TESTS: THURSTONIAN AND SSA PREDICTIONS FOR VANILLA FLAVORED YOGURTS
Authors: ROUSSEAU BENOÎT , O'MAHONY MICHAEL
Published: May 2007

The Thurstonian prediction that judges will get a higher proportion of correct 3‐AFC tests than triangle tests was confirmed using a yogurt system. As predicted, d′ values for the triangle and 3‐AFC tests corresponded. Sequential Sensitivity Analysis predictions for the sensitivity of various tasting sequences were confirmed for the 3‐AFC test but not the triangle test. Further predictions that the 2‐AFC is more sensitive than the 3‐AFC were confirmed. This increase in sensitivity more than offset the greater statistical power of the 3‐AFC. Difficulties of specifying the nature of the difference for the 2‐AFC and 3‐AFC tests were overcome using a warm‐up procedure.
SENSORY CHARACTERISTICS OF SPANISH “SERRANO” DRY‐CURED HAM
Authors: FLORES MÓNICA , INGRAM DAPHNE A. , BETT KAREN L. , TOLDRÁ FIDEL , SPANIER ARTHUR M.
Published: May 2007

A specific descriptive lexicon has been developed to evaluate the flavor of Spanish “Serrano” dry‐cured ham. Dry‐curing of pork legs produces a unique flavor difficult to define in regular meat terms. This lexicon for the flavor of dry‐cured ham may be used by researchers to study flavor‐development during the curing process. In this paper we have applied the lexicon to the study of dry‐cured flavor developed in two different manufacturing processes that differ only in the length of the drying stage. The long processed dry‐cured ham (12 months) is stronger for 8 of the 16 sensory attributes studied than the short processed dry‐cured ham (7 months). During the long curing process of the ripening‐drying stage, we found that the typical dry‐cured flavor developed was defined by three factors: “cured flavor,”“off‐flavor” and “pork flavor,” whereas in the short curing process typical dry‐cured flavor was not fully developed.
APPROACHES TO TRANSLATION PROBLEMS OF SENSORY DESCRIPTORS
Authors: ZANNONI MARIO
Published: May 2007

The globalization of the food trade has caused an increased interest in the translation of sensory descriptive terms. To deal with this issue the theory and practice of language, translation and sensory terminology were taken into account. The influence of culture on language and the relationship between words and meaning, as well as the verbalization of sensory stimuli and the organisation of a system of terminology were considered. In conclusion it was emphasized that in translation it is necessary to focus the attention primarily on stimuli rather than on words. Interest has to be placed in reality (i.e. perception and scaling of stimuli) and not on the representation of reality (i.e. words).