bluuebunny/crossref_metadata_2025_split huggingface dataset:
Relation of neonatal iron status to individual variability in neonatal temperament
Authors: Wachs Theodore D. , Pollitt Ernesto , Cueto Santiago , Jacoby Enrique , Creed‐Kanashiro Hilary 
Published: February 2005

AbstractThe relation between indices of neonatal iron status and individual differences in neonatal temperament were investigated in a sample of 148 low‐income Peruvian women and their newborn infants. Using cord blood, at birth we obtained measures of neonatal ferritin, serum iron, and hemoglobin. While neonates were still in the hospital, their behavior during a structured anthropometry examination was videotaped and subsequently coded on four temperament dimensions: activity level, negative emotionality, alertness, and soothability. The same dimensions were coded using a videotape obtained during a subsequent visit to the neonates' homes. Results indicated that lower levels of neonatal hemoglobin and serum iron were related to higher levels of negative emotionality and to lower levels of alertness and soothability. A similar pattern was found for ferritin, but only for females. For the most part, relations between neonatal iron measures and neonatal temperament were linear, operating across the full range of iron values. Our pattern of iron–temperament results could not be attributed to variation in family demographics, low birth weight, gestational age, maternal dietary intake, or markers of neonatal illness and maternal diabetes. Our findings are consistent with prior research with older infants relating iron deficiency to temperament. These results support the importance of increased research on the early functional–behavioral consequences of individual differences in iron status as well as on the mechanisms that underlie such consequences. © 2005 Wiley Periodicals, Inc. Dev Psychobiol 46: 141–153, 2005.
Chicken genome: New tools and concepts
Authors: Dequéant Mary‐Lee , Pourquié Olivier 
Published: February 2005

AbstractLast spring, the Second International Chicken Genome Workshop was held at the Stowers Institute for Medical Research, less than 2 months after the first draft of the chicken genome was publicly released in March, 2004. This major event was highly anticipated by the chicken community, because of the invaluable resources that would be newly provided. In addition, from an evolutionary standpoint, birds are the species most closely related to mammals, whose genome has been sequenced. The meeting gathered both agricultural and academic chicken communities and provided the opportunity to discuss the status of the chicken genome sequencing, the preliminary analysis of the chicken genome sequences freshly available, and the impact on avian genetic tools. Developmental Dynamics 232:883–886, 2005. © 2005 Wiley‐Liss, Inc.
Determination of Uric Acid and Norepinephrine by Chitosan‐Multiwall Carbon Nanotube Modified Electrode
Authors: Lu Guanghan , Jiang Lingyan , Song Feng , Liu Chuanyin , Jiang Liping 
Published: February 2005

AbstractA novel chemically modified electrode based on the chitosan‐multiwall carbon nanotube (MWNT) coated glassy carbon electrode (GCE) is described, which exhibited an attractive ability to determine uric acid (UA) and norepinephrine (NE) simultaneously. The responses of UA and NE merged into a large peak at a bare GCE, but yielded two well‐defined oxidation peaks at the chitosan‐MWNT modified GCE (MC/GCE). The experimental parameters were optimized, and a direct electrochemical method for the simultaneous determine for UA and NE is proposed. The MC/GCE showed good sensitivity, selectivity and stability.
Genetic Algorithm Based Potential Selection in Simultaneous Voltammetric Determination of Isoniazid and Hydrazine by Using Partial Least Squares (PLS) and Artificial Neural Networks (ANNs)
Authors: Majidi Mir Reza , Jouyban Abolghasem , Asadpour‐Zeynali Karim 
Published: February 2005

AbstractThe voltammetric behavior of isoniazid and hydrazine at an overoxidized polypyrrole modified glassy carbon electrode has been investigated. The obtained cyclic voltammograms showed that their oxidation peaks were overlapped and it is difficult to determine them individually from a mixture without separation. To overcome this limitation, a procedure was proposed for resolution of overlapped voltammetric signals from mixtures of isoniazid and hydrazine. In this procedure, genetic algorithm was used for the selection of potentials for partial least squares. A feed forward artificial neural network with back propagation error algorithm was used to process the nonlinear relationship between currents and concentrations of hydrazine and isoniazid. The proposed method was suitable for determination of isoniazid in pharmaceutical tablets and detection of hydrazine impurities in the same samples.
Slash expenses with consumer‐driven health plans
Authors: Goldberg Stephen R. , Lindquist Stanton C. , Danko Dori 
Published: February 2005

AbstractHealth‐care costs continue to soar, affecting firms of all sizes. Companies need cost relief. So, they're now looking at consumer‐driven healthcare plans instead of traditional ones. How do these innovative new plans work? What are their advantages and disadvantages? And what's the best way to implement them? The authors have some answers. © 2005 Wiley Periodicals, Inc.
How SPC can help cut costs
Authors: Roth Harold P. 
Published: February 2005

AbstractMany companies use Statistical Process Control (SPC) charts to manage and control quality. But they also provide valuable signals about why your company incurs costs—and reveal opportunities to cut costs. So SPC can help you implement many different types of cost‐reduction strategies. The author explains the basics of SPC and shows how you can use it to spot opportunities to reduce costs. © 2005 Wiley Periodicals, Inc.
Strontium‐calcium transport across the gill of rainbow trout, (Salmo gairdnerii)
Authors: Schiffman R. H. 
Published: February 2005

AbstractThis study was performed using radioactive isotopes of calcium and strontium as tracers in a perfused gill preparation. There were two levels in the uptake rates for strontium and calcium: a passive rate of 0.5 × 10−7 cm/sec, and 1.8 × 10−7 cm/sec, respectively, and a tenfold higher energy dependent rate of 5.1 × 10−7 cm/sec for strontium and 17 × 10−7 cm/sec for calcium. There was no evidence of discriminatory interaction between calcium and strontium at the passive levels of transport. Strontium was found to substitute for calcium at the active transport levels only if the calcium concentration of the environmental water was below approximately 0.1 mM Ca++/1.The rate of calcium and strontium loss from the gill was estimated as about 20 times faster than the influx rates. This caused the postulation that the net transfer of calcium ions across the gill could change, dependent upon the degree of saturation of the calcium‐binding sites within the fish.
The pathogenicity to mice of three variants of Mengo encephalomyelitis virus
Authors: Colter John S. , Campbell James B. , Hatch Lorne R. 
Published: February 2005

AbstractThe distribution of infectious virus particles in various tissues of the mouse was determined following the intraperitoneal injection of three plaque variants of Mengo encephalomyelitis virus. When lethal doses were administered, virus appeared first in the spleen and lymph nodes (suggesting that these are the primary target organs for the agents), followed by its appearance in spinal cord and brain, in which tissues the infectious titers increased progressively until the death of the animals. Low levels of virus were sometimes found in lung, heart and kidney at 24–48 hours post‐challenge, but disappeared from these tissues at later times. Virus was never detected in blood or liver, suggesting that the virus moves throughout the animal by way of the lymphatic system. When sub‐lethal doses of virus were injected, it was detectable only in spleen and lymph nodes, and disappeared from these tissues by 8–9 days post‐challenge.The LD50's for the three variants when injected by both the intraperitoneal and intracerebral routes were determined. The I.P.‐LD50's for the L (large plaque former), M (medium plaque former) and S (minute plaque former) variants in 14–16 gm mice were found to be 1, 1–5 × 104 and 2–10 × 104 p.f.u.'s, respectively. The I.C.‐LD50's were essentially the same (1–5 p.f.u.'s) for all three variants. The possibility that the differences in the I.P.‐LD50's may be due to differences in the abilities of the variants to stimulate interferon production or in their sensitivities to its antiviral action is discussed.
Electrotonic spread of current in cultured chick heart cells
Authors: Lehmkuhl D. , Sperelakis Nick 
Published: February 2005

AbstractFollowing trypsin dispersion, isolated single cells reassembled into monolayer communities categorized as strands and sheets. Two microelectrodes were mounted in bridge circuits so that current pulses could be passed through one electrode while simultaneously recording membrane potentials at both electrodes. The electrotonic spread of current was measured as a change in membrane potential (usually at electrode 2) at various distances from the site of current injection (usually at electrode 1). Most cells were driven by transmission of excitation from contiguous cells. Criteria which helped to determine when both electrodes impaled the same cell included: (a) a sharp diminution of the resting potential recorded by the first electrode to a common intermediate level following insertion of the second electrode and (b) simultaneous and congruous subthreshold changes in membrane potential. The voltage/current relationship measured at electrode 1 was linear and had a mean slope of about 7 MΩ that for electrode 2 was also linear and, in some cases at short distances, had a slope as large as that for 1, i.e., the degree of electrotonic interaction was nearly 100%. However, in other impalements at short distances, interaction was nearly zero. Therefore, the degree of electrotonic spread was not dependent upon interelectrode distance per se, but appeared to depend on whether both electrodes impaled the same cell.
Carbohydrate content during development of the slime mold, Dictyostelium discoideum
Authors: Ceccarini C. , Filosa M. 
Published: February 2005

AbstractWater soluble carbohydrates were studied at various developmental stages in the cellular slime mold, Dictyostelium discoideum. The only water soluble sugars found were, the non‐reducing disaccharide, trehalose and glucose. The level of trehalose varied very dramatically during the life cycle. Throughout the vegetative and migration stages the level of trehalose was less than 0.5% of the dry weight, but it quickly rose during culmination. During the later part of culmination trehalose reached a 1.5% level. In mature spores trehalose makes up more than 5% of the dry weight. The glucose level fluctuated very little during development. It reaches its highest level during the later part of culmination. In addition water insoluble sugars were extracted with 2.2% HCl. Their level remained constant throughout development and only increased in the complete fruiting body. The anthrone method was used for both water soluble and water insoluble carbohydrates. Trehalose was identified by IR spectroscopy.
Combined effects of chronic audio‐visual stress and thiouracil administration on the cholesterol‐fed rat
Authors: Anderson Thomas A. , Geber William F. 
Published: February 2005

AbstractWeanling Sprague‐Dawley rats fed a standard laboratory diet containing 2% cholesterol and 1% sodium cholate, when exposed to audio‐visual stress for a three‐week period, were found to have significantly heavier thyroids, lighter livers, higher serum cholesterol and increased adrenal ascorbic acid levels than similarly treated control animals. The addition of thiouracil to the ration (0.25% and 0.50%) produced the expected increases in liver and thyroid weight and serum cholesterol. Thiouracil administration also caused a marked depression in adrenal weight and adrenal ascorbic acid levels. A significant stress X diet interaction was noted on thyroid weight, suggesting that stress and diet were not independent of each other in their influence on the thyroid. The combined effects of chronic audio‐visual stress and thiouracil administration had essentially no effect on total hepatic or adrenal cholesterol levels.
Studies on synchronously dividing cultures of Euglena gracilis Klebs (strain Z). II. Patterns of biosynthesis during the cell cycle
Authors: Edmunds Leland N. 
Published: February 2005

AbstractDry weight, total protein, chlorophyll a, carotenoids, soluble protein, RNA, DNA, and total phosphorus were determined at intervals of two hours during synchronous growth of Euglena at a cell concentration of 5–10 × 104 cells/ml maintained by periodic dilution. Detailed analyses of the soluble proteins (DEAE‐cellulose fractionation) and of the intracellular distribution of phosphorus were made also. In general, a linear doubling of each of these major components occurred during the light period; there was no net synthesis during the dark. Since cell number doubled during the dark period, a halving of the amounts of the parameters in each cell occurred. The most notable exception was the stepwise synthesis of DNA during the light period: DNA replicated during the last 6 hr only of the light period, commencing at 8 hr after the onset of light. Although DNA replication was a necessary condition for cell division to occur, it was not necessarily a sufficient one. It was found that different absolute rates of synthesis exist for the different compounds, with a doubling of a given parameter sometimes being completed before the end of the light period.
The initiation of cell division in a contact‐inhibited mammalian cell line
Authors: Todaro George J. , Lazar Gerald K. , Green Howard 
Published: February 2005

AbstractThe cells of an established mouse fibroblast line, 3T3, have a high plating efficiency and grow rapidly in sparse culture, but stop growing at a very low saturation density in comparison with other lines, because 3T3 is extremely sensitive to contact inhibition of cell division. After each medium change, however, there occurs in a small fraction of the cells in a saturation density culture a series of changes that results in a single rather synchronized division 30 hours later. This is due to a macromolecular substance in the serum which appears to act by reducing the sensitivity of the cells to contact inhibition. The first recognizable event following the addition of serum to a stationary phase culture is a ten fold increase in the rate of RNA synthesis, occurring within 30 minutes. An increase in the rate of protein synthesis follows several hours later. DNA synthesis does not begin before 12 hours, but by two hours after medium change an appreciable fraction of the cells become committed to eventual DNA synthesis and cell division. The sequence of event suggests that regulation of RNA synthesis is the means by which contact inhibition controls cell division.
A multisample chamber for dehydration and critical point drying
Authors: Gollin Susanne M. , Wray Wayne 
Published: February 2005

AbstractThe principles and methods for constructing an improved chamber for dehydration and critical point drying of multiple biological samples are described. The specimen chamber design is based on vertical positioning of the electron microscope grids or coverslips and permits minimal perturbation of laminar solvent flow past the specimens. This condition is requisite for optimal exposure of samples to solvents, which is necessary for complete dehydration and drying. Fragile samples, including chromosomes, critical point dried in the multisample chamber demonstrate crisp, well‐preserved, three‐dimensional morphology.
Effects of different epoxies on avoiding wrinkles in thin sections of botanical specimens
Authors: Pihakaski Kaarina , Suoranta Ulla‐Maija 
Published: February 2005

AbstractFold or wrinkles appear frequently in thin sections cut from botanical material embedded in epoxy resin such as Epon 812 (Polysciences) or EM‐bed‐812 (Electron Microscopy Sciences). Small wrinkles may occur more or less perpendicular to the cutting direction and mostly across the cell wall, causing problems in the examination of the ultrastructure. We studied the occurrence of wrinkles and folds by methodological sectioning, with regard to block hardness, use of Formvar‐support film, and chloroform vapor. Methodological sectioning or changing the block hardness did not reduce the occurrence of wrinkles in sections. Chloroform vapor improved the result as did also the use of uncoated grid. Wrinkles and folds could be avoided completely by embedding the specimens in LX‐112 (Ladd) or ERL‐4206 (Polysciences) low‐viscosity epoxy resins, in which case Formvar‐coated grids could be used, and chloroform vapor was not necessary.
Ultrathin formvar support films for transmission electron microscopy
Authors: Davison Edwin , Colquhoun William 
Published: February 2005

AbstractWe have found that ultrathin Formvar films are easily and reliably made at an air‐water interface by the drop method. By varying the concentration of Formvar in the drop, films of different characteristics can be obtained. Concentrations of 0.25–0.4% in ethylene dichloride produce extremely flat, ultrathin, and stable films that are especially suited for shadowed and negatively stained preparations. Low concentrations (⩽ 0.1%) produce nets consisting of many tiny holes which, after carbon stabilization, are ideal for supporting high‐resolution samples. Above 0.5%, films made by the drop method develop bubbles, and this bubble defect makes them unsuitable for section support.For section support, Formvar films made by the stripping method off mica are far superior to those made off glass. The films are more uniform in surface contour and thickness. They are less readily attacked by alcohols. Consequently, they are more resistant to staining procedures involving organic solvents and continue to be strong and uniform for section support.
A comparison of specimen stage surface temperature and the GA‐1 control unit reading in Balzer's Freeze fracture microtome cold stage
Authors: Ruben George C. 
Published: February 2005

AbstractThe cold stage specimen surface in our Balzer's 300 Freeze‐etch instrument, averages 29–43°C warmer than the reading on the GA‐1 stage temperature control unit. By introduction of Indium foil seals above and below the stainless steel plug in the stage tower, the specimen cold stage surface temperatures were still 9–10°C warmer than the GA‐1 reading. After replacing the stainless steel plug with a copper plug and using Indium seals, the cold stage specimen surface was brought within 2.6°C of the GA‐1 temperature reading. In addition, the copper plug, Indium seal modified stage cools about two times faster in going from –100°C to –150°C than the normal stainless steel stage modified with Indium seals.
Ultra‐High‐Resolution electron‐beam lithography
Authors: Craighead H. G. 
Published: February 2005

AbstractA conventional TEM/STEM has been used for the fabrication of ∼ 10 nm–size structures by electron‐beam lithography. The electron microscope provides a versatile tool for studying the lithographic process with control of the beam energy, current, and profile combined with the ability to image both the probe and fabricated structures. Straightforward techniques are described for generating ultrasmall structures for physics and device experiments on both bulk substrates and on thin films. New resist processes and the effects of electron‐beam energy as studied by these techniques are discussed.
Position stabilization of EELS spectra
Authors: Kruit Pieter , Shuman Henry 
Published: February 2005

AbstractThe position of the zero‐loss peak in electron energy‐loss spectra was sensed with a double photo diode. A signal, proportional to the disturbances from a central position, was amplified and fed back into a deflection coil in order to compensate for the origin of the disturbances. Thus, slow variations of the position of characteristic edges in the EEL spectrum could be reduced by a factor 100, and 60 Hz oscillations could be reduced by a factor 5.
Polyethylene glycol (PEG) embedding and subsequent de‐embedding as a method for the correlation of light microscopy, scanning electron microscopy, and transmission electron microscopy
Authors: Kondo Hisatake , Ushiki Tatsuo 
Published: February 2005

AbstractThe polyethylene glycol (PEG) embedding and subsequent deembedding method was applied to the observation of general tissues in scanning electron microscopy (SEM). Resulting SEM images were of high quality. It was demonstrated that intermicroscopic correlation of images between light microscopy (LM), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) is easily and reliably done by means of the PEG method. In particular, the exact correlation of immuno‐LM with SEM is shown to be of potential value.
A controlled atmosphere specimen holder for transmission electron microscopy
Authors: Chan Ignatius Y. 
Published: February 2005

AbstractA controlled atmosphere specimen holder (CASH) has been developed for transmission electron microscopy (TEM) experiments. It is designed for studying the specimen's microstructure before and after treatments in various gases (H2, O2, N2, Ar, etc.) at temperatures up to 600°C. The experiments are carried out without exposing the specimen to the ambient atmosphere. No modification of the electron microscope itself is needed. The same area of the specimen can be easily located after each gas treatment, thus the changes in the microstructure can be studied directly. Preliminary results on the cyclic oxidation and reduction of a model cobalt catalyst are presented.
Cross‐sectional reflection electron microscopy of III–V compound epilayers
Authors: De Cooman B. C. , Kuesters K.‐H. , Carter C. B. 
Published: February 2005

AbstractReflection electron microscopy (REM) is shown to be applicable to the testing of the quality of AlxGa1−xAs/GaAs layer structures. Cross‐sectional images of quantum well structures with layer thickness down to 1 nm can be obtained. The practical aspects of the REM technique are presented. The most important advantages and drawbacks of cross‐sectional REM are discussed in detail.
Localization of membrane‐bound and soluble antigens using peroxidase‐labeled antibodies and preembedding immunoelectron microscopy
Authors: Osamura R. Y. , Watanabe K. 
Published: February 2005

AbstractThe immunoelectron microscopy preembedding method using peroxidase‐labeled antibodies has enabled us to localize various bioactive substances in subcellular organelles, i.e., nucleus, cytosol, perinuclear space, rough endoplasmic reticulum, Golgi complex, secretory granules, mitochondria, etc. In this text, detailed procedures and some key points for the appropriate staining are described. The applications of this technique to localize substances in various organelles and to observe ultrastructural changes of intracellular hormones are also discussed.
On the counting of electrons in high voltage electron microscopy
Authors: Pinna H. , Sirvin R. , Kihn Y. , Sevely J. , Jouffrey B. 
Published: February 2005

AbstractThis paper describes work on the counting of electrons in high voltage electron microscopy (HVEM). A reliable counting method is needed in order to perform quantitative experiments. A scintillator‐photomultiplier device has been adapted to these needs. It has been used here, in the field of electron energy loss spectroscopy. It permits the recording of the totality of the spectrum from the no‐loss peak to the inner shell excitation characteristic signals because of a dynamic equal to at least 7. A simple mounting has been made to eliminate the artifacts caused by X‐ray pulses. It is shown that HVEM is favourable to the counting of electrons, and some applications are reported.