bluuebunny/crossref_metadata_2025 huggingface dataset:
Chemical Analysis of Surfaces
Authors: Park RL
Published: March 2009

All methods of elemental identification depend on a determination of either the mass or the charge of the atomic nucleus. The nuclear charge can be inferred from the energy required to create a vacancy in an inner electron shell or from the energies of the electronic transitions involved in the decay of the vacancy. The masses are determined from the recoil momentum imparted to a noble gas ion or by removing atoms from the surface, by sputtering or high electric fields, for analysis in a mass spectrometer. Quantitative analysis, which is not yet possible, will depend on an understanding of structural information contained in secondary features of the spectrum such as line shapes or ion yields.
Quantitative Auger Electron Spectroscopy with Elemental Sensitivity Factors
Authors: Davis LE , Joshi A
Published: March 2009

An ultrahigh vacuum scanning Auger microprobe (SAM) system was used to obtain elemental sensitivity factors from selected metal alloys and oxides. The specimens were prepared to establish surface compositions equivalent to bulk concentration levels. Two-dimensional surface topographical and compositional SAM studies were made to determine the extent of impurity segregation or precipitation. Relative elemental sensitivity factors computed from published data were applied to ductile fracture surface measurements of Inconel and stainless steels. The metal alloy surface concentrations were compared to bulk concentrations. Relative elemental sensitivity factors were obtained from abraded surfaces of magnesium oxide, aluminum oxide, and silicon dioxide at primary beam energies of 3,5, and 10 keV. The results from fractured and abraded standards were compared to measurements made after sputtering with argon ions.
Four Factors Influencing Observed Rock Properties
Authors: Chamberlain PG , Van Eeckhout EM , Podnieks ER
Published: March 2009

This paper presents a review of the effects of four factors in specimen preparation that influence mechanical property tests—moisture content, orientation with respect to rock fabric, fractures, and specimen tolerances—and discusses methods developed during various Bureau of Mines testing programs for controlling these factors. Bureau and other research is cited to present problems in obtaining suitable property data arising from these factors and to define solutions to the problems. Rock mechanics researchers dealing with field sampling and laboratory testing should find the material helpful in establishing specimen handling and preparation procedures for obtaining relevant test results.
Effects of Specimen Type on the Residual Strength of Clays and Clay Shales
Authors: Townsend FC , Gilbert PA
Published: March 2009

This investigation was an examination of the effects of testing apparatus, specimen type and density, normal stress, and sequence of loading on the residual strength of various clays and clay shales. Annular shear and repeated direct shear tests were conducted on intact shale specimens with precut failure planes, while comparison rotational shear tests were conducted on the same shale material subjected to various degrees of remolding. Test results indicate that comparable residual strengths can be obtained, regardless of equipment type and procedure or degree of remolding. Supplemental annular shear tests on residual clay and silty sand show that precutting of the failure plane or the specimen density has no effect on the ϕr' value. The residual friction angle is independent of stress history and normal load [when greater than 2 kg/cm2 (1.96 × 105 Pa)].
Effect of Storage and Reconsolidation on the Properties of Champlain Clays
Authors: La Rochelle P , Sarrailh J , Roy M , Tavenas FA
Published: March 2009

A testing program has been made on samples of sensitive cemented clays at different times after sampling. When comparing results of unconfined compression tests performed on the field immediately after sampling or in the laboratory the following week, it is observed that there is a decrease in the measured strength which may be attributed to water migration; however, this effect was minimized or eliminated completely by keeping the samples in the tubes or by trimming the samples immediately after sampling. The reconsolidation of the samples to the in situ stresses restored an appreciable part of the strength lost by sampling disturbance; this effect is negligible in the case of good quality samples. Tests made on block samples which had been stored for many years in a humid room have shown a decrease in the shearing of the clay, but the preconsolidation pressure has not been affected.
Pore Water Extraction and the Effect of Sample Storage on the Pore Water Chemistry of Leda Clay
Authors: Torrance JK
Published: March 2009

In recent years, the potential significance of chemical and mineralogical influences on the behavior of the post-glacial marine clays has been increasingly recognized by the soils engineering community. The precise relationships are not known, but it seems probable that, in some cases, small differences in chemical factors may explain the differences in behavior between otherwise similar samples. In connection with an investigation of these relationships, the experiments reported in this paper were undertaken to examine the magnitude of chemical change which may occur in low-salinity Leda clay during periods of storage. Pore water extraction devices are described, and the effects on the pore water chemistry of three months storage, under a variety of standard and modified storage procedures, are reported. It is concluded that none of the storage procedures tested is entirely satisfactory, in that potentially significant changes in the pore water chemistry occurred. Finally, it is recommended that pore water chemistry be assessed more often than is the present practice when soils engineering tests are performed on Leda clay and that this be done as soon as possible after the sample is obtained from the field.
Shrinkage of Soil Specimens During Preparation for Porosimetry Tests
Authors: Zimmie TF , Almaleh LJ
Published: March 2009

Various methods of removing moisture from small soil samples were investigated. The samples were to be tested by mercury porosimetry, and one requirement is a constant volume drying process. Air-drying, oven-drying and freeze-drying procedures were used. Three different clay types were used: kaolinite, montmorillonite, and an illite. The clays were fully saturated, and compaction was achieved by using static pressure.

Freeze drying is the best practical method of drying the soil samples, as it produces the least amount of shrinkage in the soil. In certain instances, air drying and oven drying may produce satisfactory results. Total drying time for freeze drying can be accomplished in 5 to 10 h.

A simple laboratory freeze-drying system is described and operating procedures and principles discussed.

The results are applicable to the preparation of small size soil samples where it is desired to remove soil moisture and, at the same time, minimize disturbance to the soil structure.
Importance of Specimen Preparation in Microscopy
Authors: Gillott JE
Published: March 2009

Samples must be representative and specimen preparation must introduce as few changes as possible if microscopic information is to be significant in characterization and classification of soils and rocks and in interpretation of their engineering behavior. Soils and recent sediments are damaged most easily, and specimen preparation is most complex for these materials. Air drying may cause shrinkage and distortion; freeze drying and drying by the critical point method provide partial solutions. Even so, differences in the procedure followed in the removal or replacement of water can cause marked differences in appearance of specimens examined on the electron and optical microscopes. Sectioning and surface exposure may also introduce artifacts. Soil specimens for fabric study commonly are fractured when frozen, since cutting may not be used generally. The use of ion bombardment in metal coating and as an etch method is discussed, and the possibility of improving specimen preparation procedures by combining an etch technique with freeze drying is outlined.
Use of Ultrasonic Energy for Disaggregation of Soil Samples
Authors: Johnson AI , Mostoh RP
Published: March 2009

A method for faster and more nearly complete dispersion of soil samples for particle size analysis now appears feasible. Using agitation by ultrasonic energy, disaggregation and dispersion appeared to be as thorough in 10 min as by mechanical preparation through a sieve with 0.0625-mm openings. The ultrasonic agitation appeared to cause no deleterious effect on the primary particle sizes. The time and effort required to obtain high quality dispersion is much less for ultrasonic than for mechanical techniques, especially for heavy soils.
Hydrogen Embrittlement Testing
Authors: Raymond L
Published: March 2009

Description

Nineteen papers cover internal hydrogen embrittlement, testing for relative susceptibility, testing for hydrogen pickup during processing, mechanical delay-time test, hydrogen defection methods, hydrogen environment embrittlement
Rubber and Related Products: New Methods for Testing and Analyzing
Authors: King WH , Rogers TH
Published: March 2009

Description

One of the most comprehensive texts of its time, it contain 12 papers dealing with such topics as viscosity, vulcanizers, plasticity, theometrics, dynamic testing, physical testing, tensile testing and fatigue
Instrumentation for Monitoring Air Quality
Authors: Barras RC
Published: March 2009

Description

Sixteen papers give an overview of modern air monitoring instrumentation. Every air pollution engineer should have a copy.
Instrumented Impact Testing
Authors: DeSisto TS
Published: March 2009

Description

The symposium on Instrumented Impact Testing was presented at the Seventy-sixth Annual Meeting of the American Society for Testing and Materials held in Philadelphia, Pa. 24—29 June 1973. Committee E28 on Mechanical Testing sponsored the symposium. T. S. DeSisto, Army Materials and Research Center, presided as symposium chairman.
Evolution of the International Practical Temperature Scale of 1968
Authors: Bliss P
Published: March 2009

Description

This publication is a collection of papers gathered by ASTM Subcommittee E20.07 on Fundamentals in Thermometry. The papers recount the origin and history of the International Practical Temperature Scales, leading up to the most recent, IPTS-68.
Foreign Object Impact Damage To Composites
Authors: Greszczuk LB
Published: March 2009

Description

The Symposium on Foreign Object Impact Damage to Composites was held at the American Society for Testing and Materials Headquarters in Philadelphia, Pa., on 20 Sept. 1973. The symposium was sponsored by ASTM Committee D30 on High Modulus Fibers and Their Components. L. B. Greszczuk, McDonnell Douglas Astronautics Co., served as the symposium chairman.
Fatigue of Composite Materials
Authors: Hancock JR
Published: March 2009

Description

The symposium on Fatigue of Composite Materials was presented at December Committee Week of the American Society for Testing and Materials held in Bal Harbour, Fla., 3-4 Dec. 1973. Committee E09 on Fatigue sponsored the symposium in cooperation with the Institute of Metals Division Composites Committee of the American Institute of Mining, Metallurgical, and Petroleum Engineers. J. R. Hancock, Midwest Research Institute, presided as symposium chairman.
Monitoring Structural Integrity by Acoustic Emission
Authors: Spanner JC , McElroy JW
Published: March 2009

Description

The symposium on Monitoring Structural Integrity by Acoustic Emission was presented in Ft. Lauderdale, Fla., 17-18 Jan. 1974. The symposium was sponsored by Committee E07 on Nondestructuve Testing, American Society for Testing and Materials. J. C. Spanner, Westinghouse Hanford Co., presided as symposium chairman. J. W. McElroy, Philadelphia Electric Co., presided as symposium co-chairman.
Metrication—Managing the Industrial Transition
Authors: Liptai RG , Pearson JW
Published: March 2009

Description

The first complete book of its kind gives the background, industrial standards, industrial changeover and case histories for the metric conversion.
Manual on Statistical Planning and Analysis
Authors: Little RE
Published: March 2009

Description

In 1949 Committee E09 on Fatigue published ASTM STP 91, Manual on Fatigue Testing. Seven years later E09 published ASTM STP 91A, A Guide for Fatigue Testing and the Statistical Analysis of Fatigue Data. Both publications were modest efforts, presenting what was then considered the current practice and views of Committee E09 members. Subsequently effort was expended intermittently in Committee E09 for over a decade in various attempts to revise and expand these STP's to reflect advances in the state of the art and in statistical analyses. This activity ultimately led to ASTM STP 566, Handbook of Fatigue Testing, and to the present Manual on Statistical Planning and Analysis for Fatigue Experiments.
Correlating Sensory Objective Measurements—New Methods for Answering Old Problems
Authors: Powers JJ , Moskowitz HR
Published: March 2009

Description

The symposium on Correlating Sensory Objective Measurements: New Methods for Answering Old Problems was held at ASTM in Philadelphia, Pa., 11—12 Nov. 1974. Committee E18 on Sensory Evaluation of Materials and Products sponsored the symposium. J. J. Powers, University of Georgia College of Agriculture, presided as a symposium chairman, and H. R. Moskowitz, U.S. Army Natick Laboratories, served as symposium co-chairman.
Living with Marginal Aggregates
Authors: Philleo RE
Published: March 2009

Description

The symposium on Living with Marginal Aggregates was held at the Seventy-eighth Annual Meeting of the American Society for Testing and Materials held in Montreal, Canada, 22—27 June 1975. The symposium was sponsored by Committee C09 on Concrete and Concrete Aggregates, R. E. Philleo, chairman, and organized by Subcommittee C09.01.02 on Papers and Symposia, C. J. Andres, C. H. Best, and L. M. M. Dolar-Mantuani. C. H. Best, Kansas State University, presided as symposium chairman.
Calibration in Air Monitoring
Authors: Chapman RL , Sheesley DC
Published: March 2009

Description

The Symposium on Calibration in Air Monitoring was presented at the University of Colorado at Boulder, Colo., 5-7 Aug., 1975. The symposium was sponsored by The American Society for Testing and Materials through its Committee D-22 on Methods of Sampling and Analysis of Atmospheres. R. L. Chapman, Beckman Instruments, Inc., presided as symposium chairman. D. C. Sheesley, Ambient Analysis, Inc., presided as symposium cochairman.
Fractography—Microscopic Cracking Processes
Authors: Beachem CD , Warke WR
Published: March 2009

Description

The Symposium on Fractograph—Microscopic Cracking Processes was held at the Seventy-eighth Annual Meeting of the American Society for Testing and Materials held in Montreal, Canada, 22-27 June 1975. ASTM Commitee E24 on Fracture Testing of Metals sponsored the symposium. C. D. Beachem, Naval Research Laboratory, and W. R. Warke, Illinois Institute of Technology, served as symposium cochairmen.
Cracks and Fracture
Authors: Swedlow JL , Williams ML
Published: March 2009

Description

This publication, Cracks and Fracture, contains papers presented at the Ninth National Symposium on Fracture Mechanics which was held at the University of Pittsburgh, Pittsburgh, Pa., 25-27 Aug. 1975. The Symposium was sponsored by Committee E24 on Fracture Testing of Metals of the American Society for Testing and Materials. J. L. Swedlow, Carnegie-Mellon University, and M. L. Williams, University of Pittsburgh, presided as symposium co-chairmen.
Stress Corrosion—New Approaches
Authors: Craig HL
Published: March 2009

Description

The symposium on New Approaches to Stress Corrosion was presented at the Seventy-eighth Annual Meeting of the American Society for Testing and Materials held in Montreal, Canada, 22-27 June 1975. Committee G01 on Corrosion of Metals sponsored the symposium. H. L. Craig, Jr., University of Miami, presided as symposium chairman and editor of this publication.
Selection and Use of Wear Tests for Metals
Authors: Bayer RG
Published: March 2009

Description

An excellent state-of-the-art book containing seven papers that treat a variety of wear test problems and techniques.
Low-Temperature Properties of Bituminous Materials and Compacted Bituminous Paving Mixtures
Authors: Marek CR
Published: March 2009

Description

Six papers help both the materials engineer and pavement design engineer in finding solutions to performance of flexible pavements at low temperatures.
Chloride Corrosion of Steel in Concrete
Authors: Tonini DE , Dean SW
Published: March 2009

Description

The symposium on Chloride Corrosion of Steel in Concrete was presented at the Seventy-ninth Annual Meeting of the American Society for Testing and Materials held in Chicago, Ill., 27 June-2 July 1976. Committee G01 on Corrosion of Metals sponsored the symposium. D. E. Tonini, American Hot Dip galvanizers Association, Inc., and S. W. Dean, Jr., Air Products and Chemicals, Inc., presided as symposium cochairmen and also as editors of this publication.
Flaw Growth and Fracture
Authors: Barsom JM
Published: March 2009

Description

This publication, Flaw Growth and Fracture, contains papers presented at the Tenth National Symposium on Fracture Mechanics which was held 23-25 August 1976 at Philadelphia, Pa. The American Society for Testing and Materials' Committee E24 on Fracture Testing of Metals sponsored the symposium. J. M. Barsom, U. S. Steel Corporation, Monroeville, Pa., served as symposium chairman.
Zirconium in the Nuclear Industry
Authors: Lowe AL , Parry GW
Published: March 2009

Description

45 papers present vitally important data on the behavior of zirconium alloys in nuclear reactor environments.
Aquatic Toxicology and Hazard Evaluation
Authors: Mayer FL , Hamelink JL
Published: March 2009

Description

A pioneer attempt to assess the safety of chemicals that directly of indirectly affect water based ecosystems. 22 papers provide state-of-the-art for research approaches, new applications of old methods, new data on several pesticides and other chemicals.
Bacterial Indicators/Health Hazards Associated with Water
Authors: Hoadley AW , Dutka BJ
Published: March 2009

Description

The International Symposium on Bacterial Indicators of Potential Health Hazards Associated With Water was held 28-29 June 1976 at Chicago, Ill. The American Society for Testing and Material's Committee D19 on Water sponsored the symposium, and A. W. Hoadley, Georgia Institute of Technology, served as symposium chairman. B. J. Dutka, Canada Centre for Inland Waters, and A. W. Hoadley served as editors of this publication.
Fatigue of Filamentary Composite Materials
Authors: Reifsnider KL , Lauraitis KN
Published: March 2009

Description

A current worldwide review on traditional indicators used in water quality assessment. 25 papers cover automated monitoring techniques, classifications of environmental enteric strains, r-factors and salmonellae, use of bacteria in evaluation of water quality and water.
Cyclic Stress-Strain and Plastic Deformation Aspects of Fatigue Crack Growth
Authors: Impellizzeri LF
Published: March 2009

Description

The symposium on Cyclic Stress-Strain and Plastic Deformation Aspects of Fatigue Crack Growth was presented at a meeting held in St. Louis, Mo., 2—8 May 1976. The symposium was sponsored by the American Society for Testing and Materials through its Committee E09 on Fatigue. L. F. Impellizzeri, McDonnell Aircraft Company, presided as symposium chairman.
ASTM Manual on Zirconium and Hafnium
Authors: Schemel JH
Published: March 2009

Description

A basic information publication for engineers, students, purchasing agents, and others who do not work regularly with zirconium. Terminology, design calculations, machining and fabrication methods, and the unusual features covered.
Formability Topics—Metallic Materials
Authors: Niemeier BA , Schmieder AK , Newby JR
Published: March 2009

Description

This special technical publication, Formability Topics—Metallic Materials, contains papers presented at the 1977 Symposium on Formability, held in Toronto, Canada, on 4 May 1977. The symposium was sponsored by the American Society for Testing and Materials through its Committee E28 on Mechanical Testing. B. A. Niemeier, Reynolds Metals Company, and A. K. Schmieder, General Electric Company, presided as cochairmen of the symposium; B. A. Niemeier and J. R. Newby, Armco Steel Corporation, served as editors of this publication.
Toughness and Fracture Behavior of Titanium
Authors: Broadwell RG , Hickey CF
Published: March 2009

Description

The symposium on Toughness and Fracture Behavior of Titanium was presented at May Committee Week of the American Society for Testing and Materials held in Toronto, Ontario, Canada, 1–6 May 1977. Committee J01 on Effect of Temperature on the Properties of Metals, which is a joint committee of the American Society for Testing and Materials, American Society of Mechanical Engineers, and Metal Properties Council, sponsored the symposium. R. G. Broadwell, TIMET, and C. F. Hickey, Jr., Army Materials and Mechanics Research Center, presided as symposium chairmen.
Dynamic Geotechnical Testing
Authors: Silver ML , Tiedemann D
Published: March 2009

Description

A volume of 19 papers that evaluates present laboratory practices as well as field-testing to determine dynamic testing, improvements to existing techniques and new techniques are discussed.
Chemical Dispersants for the Control of Oil Spills
Authors: McCarthy LT , Lindblom GP , Walter HF
Published: March 2009

Description

The symposium on Chemical Dispersants for the Control of Oil Spills was held at Williamsburg, Va., 4-5 Oct. 1977. The symposium was sponsored by Committee F20 on Spill Control Systems, American Society for Testing and Materials. L. T. McCarthy, Jr., presided as symposium chairman. The editors of this publication are L. T. McCarthy, Jr., G. P. Lindblom, Exxon Chemical Company, and H. F. Walter, Department of Energy.
Engineering Dielectrics Volume I Corona Measurement and Interpretation
Authors: Bartnikas R , McMahon EJ
Published: March 2009

Description

The ASTM series on Engineering Dielectrics is devoted to a comprehensive presentation of topics related to electrical insulating materials that concern their dielectric properties, their use, and evaluation for application for electrical power and communication apparatus structures and devices. The first volume in this series deals with corona or partial discharge measurements. The contents of Volume 1 have been designed so that the contents can be used as a reference source on corona discharges by specialist in the field s well as an introductory test by beginners. Each chapter has been arranged to provide an introduction followed by an extensive review treatise on a particular aspect of the corona discharge field. Volume 1 covers the entire field of corona measurement and detection on electrical insulating materials and apparatus structures such as capacitor, cables, transformers, and electrical machines
Methods and Measurements of Periphyton Communities: A Review
Authors: Weitzel RL
Published: March 2009

Description

This publication, Methods and Measurements of Periphyton Communities: A Review, was sponsored by the American Society for Testing and Materials through its Committee D19 on Water. R. L. Weitzel, Hazleton Environmental Sciences Corporation, served as editor of this publication.
Commercial Opportunities for Advanced Composites
Authors: Watts AA
Published: March 2009

Description

The papers presented provide a review of reinforcement and matrix materials; fabrication processes for composite materials and structures; properties, cost and commercial application of composite materials; and barriers to the use of composite materials.
Classification of NPY-Expressing Neocortical Interneurons
Authors: Karagiannis Anastassios , Gallopin Thierry , Dávid Csaba , Battaglia Demian , Geoffroy Hélène , Rossier Jean , Hillman Elizabeth M. C. , Staiger Jochen F. , Cauli Bruno
Published: March 2009

Neuropeptide Y (NPY) is an abundant neuropeptide of the neocortex involved in numerous physiological and pathological processes. Because of the large electrophysiological, molecular, and morphological diversity of NPY-expressing neurons their precise identity remains unclear. To define distinct populations of NPY neurons we characterized, in acute slices of rat barrel cortex, 200 cortical neurons of layers I–IV by means of whole-cell patch-clamp recordings, biocytin labeling, and single-cell reverse transcriptase-PCR designed to probe for the expression of well established molecular markers for cortical neurons. To classify reliably cortical NPY neurons, we used and compared different unsupervised clustering algorithms based on laminar location and electrophysiological and molecular properties. These classification schemes confirmed that NPY neurons are nearly exclusively GABAergic and consistently disclosed three main types of NPY-expressing interneurons. (1) Neurogliaform-like neurons exhibiting a dense axonal arbor, were the most frequent and superficial, and substantially expressed the neuronal isoform of nitric oxide synthase. (2) Martinotti-like cells characterized by an ascending axon ramifying in layer I coexpressed somatostatin and were the most excitable type. (3) Among fast-spiking and parvalbumin-positive basket cells, NPY expression was correlated with pronounced spike latency. By clarifying the diversity of cortical NPY neurons, this study establishes a basis for future investigations aiming at elucidating their physiological roles.
NKCC1-Dependent GABAergic Excitation Drives Synaptic Network Maturation during Early Hippocampal Development
Authors: Pfeffer Carsten K. , Stein Valentin , Keating Damien J. , Maier Hannes , Rinke Ilka , Rudhard York , Hentschke Moritz , Rune Gabriele M. , Jentsch Thomas J. , Hübner Christian A.
Published: March 2009

A high intracellular chloride concentration in immature neurons leads to a depolarizing action of GABA that is thought to shape the developing neuronal network. We show that GABA-triggered depolarization and Ca2+transients were attenuated in mice deficient for the Na–K–2Cl cotransporter NKCC1. Correlated Ca2+transients and giant depolarizing potentials (GDPs) were drastically reduced and the maturation of the glutamatergic and GABAergic transmission in CA1 delayed. Brain morphology, synaptic density, and expression levels of certain developmental marker genes were unchanged. The expression of lynx1, a protein known to dampen network activity, was decreased. In mice deficient for the neuronal Cl−/HCO3−exchanger AE3, GDPs were also diminished. These data show that NKCC1-mediated Cl−accumulation contributes to GABAergic excitation and network activity during early postnatal development and thus facilitates the maturation of excitatory and inhibitory synapses.
Evidence for a Proprioception-Based Rapid On-Line Error Correction Mechanism for Hand Orientation during Reaching Movements in Blind Subjects
Authors: Gosselin-Kessiby Nadia , Kalaska John F. , Messier Julie
Published: March 2009

The contribution of visual experience to the perception and sensorimotor control of spatial orientation of the hand was investigated in blind subjects. In “orientation-matching” tasks, subjects aligned a match handle held in their right hand to a target handle held in their left hand and fixed in different orientations, with both arms outstretched. In “letter-posting” task 1, the same subjects reached out and simultaneously oriented their right hand to insert the match handle into a target slot fixed in the same range of orientations. Orientations were signaled proprioceptively by a reference handle held in the left hand. Final hand orientation errors were smaller when blind subjects simultaneously reached out and rotated their hand to insert the match handle into the target slot in letter-posting task 1 than when they held their arm extended and aligned the handles in the orientation-matching task. In letter-posting task 2, blind subjects first aligned their hand to the orientation of the target and then subsequently reached to the target with the instruction to not change hand orientation during reaching. Despite the instruction, subjects showed a reduction in absolute hand orientation error from the beginning to the end of the reach. In all tasks, performance of blind subjects was very similar to that of blindfolded normally sighted subjects. These findings provide the first evidence of an automatic on-line error-correction mechanism for hand orientation guided only by proprioceptive inputs during reaching in blind subjects, and reveal that the on-line mechanism does not depend on prior visual experience.
The Cleavage Products of Amyloid-β Precursor Protein Are Sorted to Distinct Carrier Vesicles That Are Independently Transported within Neurites
Authors: Muresan Virgil , Varvel Nicholas H. , Lamb Bruce T. , Muresan Zoia
Published: March 2009

The amyloid-β (Aβ) precursor protein (APP), a transmembrane protein that undergoes proteolytic cleavage into defined fragments, has been implicated in axonal transport. The proposed role of APP as a vesicle receptor for the microtubule motor kinesin-1 has relevance for the pathogenesis of Alzheimer's disease. Nevertheless, this function, which relies on the transport to the cell periphery of full-length APP rather than its cleavage fragments, remains controversial. Other proposed functions of APP, such as regulating transcription, neurogenesis, cell movement, or neurite growth also rely on APP's presence as a full-length protein at the cell surface, implying that APP cleavage occurs after its transport to the cell periphery. To test this hypothesis, we mapped the localization of various APP epitopes in neurons in culture and in the mouse brain. Surprisingly, epitopes from the N-terminal, C-terminal, and central (Aβ) domains of APP each showed a distinct distribution throughout the cell and rarely colocalized. Within neurites, these epitopes were localized to distinct transport vesicles that associated with different sets of microtubules and, occasionally, actin filaments. C-terminal APP fragments were preferentially transported into neurites as phosphorylated forms, entered the lamellipodium and filopodia of growth cones, and concentrated in regions of growth cone turning and advancement (unlike the N-terminal and Aβ fragments). We conclude that, under normal conditions, the proteolytic cleavage of APP primarily occurs before its sorting into axonal transport vesicles and the cleaved fragments segregate into separate vesicle populations that reach different destinations, and thus have different functions.
Behavioral and Neural Changes after Gains and Losses of Conditioned Reinforcers
Authors: Seo Hyojung , Lee Daeyeol
Published: March 2009

Human behaviors can be more powerfully influenced by conditioned reinforcers, such as money, than by primary reinforcers. Moreover, people often change their behaviors to avoid monetary losses. However, the effect of removing conditioned reinforcers on choices has not been explored in animals, and the neural mechanisms mediating the behavioral effects of gains and losses are not well understood. To investigate the behavioral and neural effects of gaining and losing a conditioned reinforcer, we trained rhesus monkeys for a matching pennies task in which the positive and negative values of its payoff matrix were realized by the delivery and removal of a conditioned reinforcer. Consistent with the findings previously obtained with non-negative payoffs and primary rewards, the animal's choice behavior during this task was nearly optimal. Nevertheless, the gain and loss of a conditioned reinforcer significantly increased and decreased, respectively, the tendency for the animal to choose the same target in subsequent trials. We also found that the neurons in the dorsomedial frontal cortex, dorsal anterior cingulate cortex, and dorsolateral prefrontal cortex often changed their activity according to whether the animal earned or lost a conditioned reinforcer in the current or previous trial. Moreover, many neurons in the dorsomedial frontal cortex also signaled the gain or loss occurring as a result of choosing a particular action as well as changes in the animal's behaviors resulting from such gains or losses. Thus, primate medial frontal cortex might mediate the behavioral effects of conditioned reinforcers and their losses.
Rapid Synaptic Depression Explains Nonlinear Modulation of Spectro-Temporal Tuning in Primary Auditory Cortex by Natural Stimuli
Authors: David Stephen V. , Mesgarani Nima , Fritz Jonathan B. , Shamma Shihab A.
Published: March 2009

In this study, we explored ways to account more accurately for responses of neurons in primary auditory cortex (A1) to natural sounds. The auditory cortex has evolved to extract behaviorally relevant information from complex natural sounds, but most of our understanding of its function is derived from experiments using simple synthetic stimuli. Previous neurophysiological studies have found that existing models, such as the linear spectro-temporal receptive field (STRF), fail to capture the entire functional relationship between natural stimuli and neural responses. To study this problem, we compared STRFs for A1 neurons estimated using a natural stimulus, continuous speech, with STRFs estimated using synthetic ripple noise. For about one-third of the neurons, we found significant differences between STRFs, usually in the temporal dynamics of inhibition and/or overall gain. This shift in tuning resulted primarily from differences in the coarse temporal structure of the speech and noise stimuli. Using simulations, we found that the stimulus dependence of spectro-temporal tuning can be explained by a model in which synaptic inputs to A1 neurons are susceptible to rapid nonlinear depression. This dynamic reshaping of spectro-temporal tuning suggests that synaptic depression may enable efficient encoding of natural auditory stimuli.
Diffusion-Weighted Magnetic Resonance Imaging Reversal by Gene Knockdown of Matrix Metalloproteinase-9 Activities in Live Animal Brains
Authors: Liu Christina H. , You Zerong , Liu Charng-Ming , Kim Young R. , Whalen Michael J. , Rosen Bruce R. , Liu Philip K.
Published: March 2009

The involvement of matrix metalloproteinase-9 (MMP-9) activities in the development of abnormal water diffusion in the brain after cardiac arrest is not fully understood. We used magnetic resonance imaging to determine the correlation between MMP-9 activity and the mechanism of abnormal water diffusion after global cerebral ischemia (GCI)-induced brain damage in C57black6 mice. We induced GCI in mice by occluding both carotid arteries for 60 min, then allowing reperfusion. We labeled a short DNA that targets mmp-9 mRNA activity [phosphorothioate-modified oligodeoxynucleotide (sODN)-mmp9] or a control probe without intracellular target (sODN-Ran) with iron-based MR contrast agent [superparamagnetic iron oxide nanoparticle (SPION)-mmp9 or SPION-Ran] or fluorescein isothiocyanate (FITC)-sODN-mmp9 or FITC-sODN-Ran; we then delivered these probes by intracerebroventricular infusion or intraperitoneal injection within 3 h of reperfusion. At low dose (120 pmol/kg) the SPION-mmp9 probe was retained at significant levels in the striatum and cortex of living brains 10 h after GCI. Probe retention was validated by similar elevation of mmp-9 mRNA and antigens in postmortem samples taken from regions that exhibited GCI-induced hyperintensity in diffusion-weighted imaging, and a significant reduction in apparent diffusion coefficient (rADC,p= 0.0006,n= 12). At a higher dose (120 nmol/kg), the FITC-sODN-mmp9 probe revealed significant knockdown of MMP-9 activity, per zymography, and a reversal of striatal rADC (p= 0.004,n= 6). These observations were not duplicated in the control group. We conclude that expression of mmp-9 mRNA is associated with abnormal ADC after GCI.
Cellular Plasticity for Group I mGluR-Mediated Epileptogenesis
Authors: Bianchi Riccardo , Chuang Shih-Chieh , Zhao Wangfa , Young Steven R. , Wong Robert K. S.
Published: March 2009

Stimulation of group I metabotropic glutamate receptors (mGluRs) by the agonist (S)-dihydroxyphenylglycine in the hippocampus transforms normal neuronal activity into prolonged epileptiform discharges. The conversion is long lasting in that epileptiform discharges persist after washout of the inducing agonist and serves as a model of epileptogenesis. The group I mGluR model of epileptogenesis took on special significance because epilepsy associated with fragile X syndrome (FXS) may be caused by excessive group I mGluR signaling. At present, the plasticity mechanism underlying the group I mGluR-mediated epileptogenesis is unknown.ImGluR(V), a voltage-gated cationic current activated by group I mGluR agonists in CA3 pyramidal cells in the hippocampus, is a possible candidate.ImGluR(V)activation is associated with group I mGluR agonist-elicited epileptiform discharges. ForImGluR(V)to play a role in epileptogenesis, long-term activation of the current must occur after group I mGluR agonist exposure or synaptic stimulation. We observed thatImGluR(V), once induced by group I mGluR agonist stimulation in CA3 pyramidal cells, remained undiminished for hours after agonist washout. In slices prepared from FXS model mice, repeated stimulation of recurrent CA3 pyramidal cell synapses, effective in eliciting mGluR-mediated epileptiform discharges, also induced long-lastingImGluR(V)in CA3 pyramidal cells. Similar to group I mGluR-mediated prolonged epileptiform discharges, persistentImGluR(V)was no longer observed in preparations pretreated with inhibitors of tyrosine kinase, of extracellular signal-regulated kinase 1/2, or of mRNA protein synthesis. The results indicate thatImGluR(V)is an intrinsic plasticity mechanism associated with group I mGluR-mediated epileptogenesis.
Evolutionary Conservation of Vertebrate Blood–Brain Barrier Chemoprotective Mechanisms inDrosophila
Authors: Mayer Fahima , Mayer Nasima , Chinn Leslie , Pinsonneault Robert L. , Kroetz Deanna , Bainton Roland J.
Published: March 2009

Pharmacologic remedy of many brain diseases is difficult because of the powerful drug exclusion properties of the blood–brain barrier (BBB). Chemical isolation of the vertebrate brain is achieved through the highly integrated, anatomically compact and functionally overlapping chemical isolation processes of the BBB. These include functions that need to be coordinated between tight diffusion junctions and unidirectionally acting xenobiotic transporters. Understanding of many of these processes has been hampered, because they are not well mimicked byex vivomodels of the BBB and have been experimentally difficult and expensive to disentangle in intact rodent models. Here we show that theDrosophila melanogaster(Dm) humoral/CNS barrier conserves the xenobiotic exclusion properties found in the vertebrate vascular endothelium. We characterize a fly ATP binding cassette (ABC) transporter, Mdr65, that functions similarly to mammalian xenobiotic BBB transporters and show that varying its levels solely in theDmBBB changes the inherent sensitivity of the barrier to cytotoxic pharmaceuticals. Furthermore, we demonstrate orthologous function between Mdr65 and vertebrate ABC transporters by rescuing chemical protection of theDmbrain with human MDR1/Pgp. These data indicate that the ancient origins of CNS chemoprotection extend to both conserved molecular means and functionally analogous anatomic spaces that together promote CNS selective drug partition. Thus,Dmpresents an experimentally tractable system for analyzing physiological properties of the BBB in an intact organism.
Regulation of Group I Metabotropic Glutamate Receptor Trafficking and Signaling by the Caveolar/Lipid Raft Pathway
Authors: Francesconi Anna , Kumari Ranju , Zukin R. Suzanne
Published: March 2009

Endocytic trafficking of neurotransmitter receptors is critical to neuronal signaling and activity-dependent synaptic plasticity. Although the importance of clathrin-mediated endocytosis in receptor trafficking in neurons is well established, the contribution of the caveolar/lipid raft pathway has been little explored. Here, we show that caveolin-1, an adaptor protein that associates with lipid rafts and the main coat protein of caveolae, binds to and colocalizes with metabotropic glutamate receptors 1/5 (mGluR1/5). The interaction with caveolin-1 controls the rate of constitutive mGluR1 internalization, thereby regulating expression of the receptor at the cell surface. Consistent with a role for caveolin-1 in mGluR trafficking, we show that mGluR1/5 associate with lipid rafts in the brain and that their constitutive internalization is mediated, in both heterologous cells and neurons, by caveolar/raft-dependent endocytosis. We further show that caveolin-1 attenuates mGluR1-dependent activation of extracellular signal-regulated kinase (ERK)–mitogen-activated protein kinase (MAPK) signaling, an effect that is abolished in cells expressing mutant mGluR1 lacking intact caveolin binding motifs. Neurons from caveolin-1 knock-out mice show enhanced basal ERK1/2 phosphorylation and prolonged ERK1/2 activation in response to stimulation with DHPG [(RS)-3,5-dihydroxyphenylglycine], a group I mGluR-selective agonist. Together, these findings underscore the importance of caveolar rafts in neurons and suggest that this pathway might play an important role in synapse formation and plasticity.
Memory and Musical Expectation for Tones in Cultural Context
Authors: Curtis Meagan E. , Bharucha Jamshed J.
Published: March 2009

WE EXPLORED HOW MUSICAL CULTURE SHAPES ONE'S listening experience.Western participants heard a series of tones drawn from either the Western major mode (culturally familiar) or the Indian thaat Bhairav (culturally unfamiliar) and then heard a test tone. They made a speeded judgment about whether the test tone was present in the prior series of tones. Interactions between mode (Western or Indian) and test tone type (congruous or incongruous) reflect the utilization of Western modal knowledge to make judgments about the test tones. False alarm rates were higher for test tones congruent with the major mode than for test tones congruent with Bhairav. In contrast, false alarm rates were lower for test tones incongruent with the major mode than for test tones incongruent with Bhairav. These findings suggest that one's internalized cultural knowledge may drive musical expectancies when listening to music of an unfamiliar modal system.
Physical activity in prevention and treatment of diabetes
Authors: Apor Péter
Published: March 2009

Az áttekintés érinti az egyszeri fizikai terhelés hatását a vércukorszintre, a rendszeres testmozgás (edzés) jelenleg ismert vagy feltételezett hatásmechanizmusait a szénhidrát- és zsíranyagcserére. Az egyszeri testmozgás alatt és az azt követő órákban a cukor felhasználása javul, „az edzés úgy hat, mint az inzulin”. A megfelelő edzés növeli a test zsírraktárainak elégetését, a testzsír csökkenése, a karcsúbb alkat a diéta és a testmozgás kombinációjával megőrizhető. Részletezi a közlemény a „mindenkinek ajánlott” testmozgást, valamint az 1-es és 2-es típusú cukorbetegek edzésének speciális szempontjait. Az egyén és a társadalom szempontjából a kardiometabolikus megbetegedések ellen a legésszerűbb lenne a testzsír-felszaporodás megelőzése testmozgással és okos táplálkozással.
Role of myofibroblast in inflammatory bowel disease and tumor genesis
Authors: Valcz Gábor , Krenács Tibor , Molnár Béla , Tulassay Zsolt
Published: March 2009

A vastagbél stromasejtjeinek és az azokat körülvevő mikrokörnyezetnek elsődleges szerepe van a gyulladásos folyamatok szabályozásában, a tumorok kialakításában és az áttétek képzésében. A gyulladásos folyamatokban és az azt követő szöveti regenerációban alapvető jelentőségűek a myofibroblastok, amelyek által termelt molekulák hatnak az immunrendszer sejtjeire és a hámsejtek proliferációjára. A daganatok myofibroblastokat aktiválhatnak, amelyek fokozott és megváltozott regulátoros ligand (citokin, kemokin, kemotaktikus és növekedési faktorok) termelése őssejt-aktiváción keresztül a hámsejtek kontrollálatlan szaporodásához vezethet. Dolgozatunkban a myofibroblastokkal kapcsolatos tudnivalókat foglaljuk össze, és ismertetjük szerepüket a gyulladásos és a neoplasztikus folyamatokban.
Ensaio de cultivares e híbridos de morangueiro, Jundiaí, 1971
Authors: Camargo Leocádio de Souza , Scaranari Hélio José , Igue Toshio
Published: March 2009

São apresentados os resultados de ensaio de competição de cinco cultivares e híbridos de morangueiro (Fragaria híbridos), realizado em 1971 na Estação Experimental de Jundiaí, SP, região de altitude aproximada de 715 m e latitude 23° e 6'S. O município de Jundiaí e os municípios vizinhos são os maiores produtores de morango do Brasil. Os cultivares estudados foram os seguintes: Campinas, Monte Alegre, Mantiqueira, Híbrido 1AC-4703 e Dr. Morère ou Comum. A colheita se estendeu de maio a novembro, para os cultivares Campinas, Monte Alegre e Híbrido IAC-4703. Foram tardios na produção de frutos, colhendo-se de julho a novembro, os cultivares Mantiqueira e Dr. Morère ou Comum. Com relação a precocidade, produtividade e características comerciais de produto - tamanho, paladar, coloração, firmeza dos frutos - obtiveram-se resultados significantemente superiores com os cultivares Campinas e Monte Alegre.
Estudo comparativo de cultivares de trigo em latossolo roxo no vale do Paranapanema
Authors: Camargo Carlos Eduardo de Oliveira , Issa Eduardo
Published: March 2009

Este trabalho foi executado com o propósito de estudar o comportamento de diferentes cultivares de trigo, na região tritícola do Estado de São Paulo. Foram instaladas cinco experiências em Latossolo Roxo, no Vale do Paranapanema, sendo duas em 1971 e três em 1972. Os cultivares Pel 4178-67, IAC-5, IAS-55, IRN-526-63, Londrina, Pitic-62, Cotiporã, IAS-54, LA-1434 e C-17 foram os que apresentaram maior produtividade por unidade de área; os cultivares Pel 4178-67 e Paraguai-214 mostraram-se resistentes às raças prevalentes de ferrugem do colmo e da folha. Entre os cultivares estudados, BH-1146, IAS-51, IAS-54, IAC-5, IRN-526-63, LA-1434, Pel 1403-64, S-12, S-43, Santa Elena, Pel 13180-65 foram suscetíveis à ferrugem da folha, e IAC-8, BH-1146, S-43, Pel 13295-65, IAC-5, S-12, Cotiporã, Pel 14603-64 e Santa Elena suscetíveis ao acamamento.
Efeitos da granulometria, formas e quantidades de materiais corretivos na acidez do solo
Authors: Gargantini Hermano
Published: March 2009

Este trabalho foi realizado com o objetivo de estudar o efeito da granulometria e da quantidade de dois materiais corretivos da acidez do solo na produção de milho e trigo, bem como em propriedades químicas do solo. A parte experimental foi conduzida em casa de vegetação, em vasos de Mitscherlich, com amostra de Latossolo Vermelho-Escuro orto, coletada no município de Itapetininga. As culturas utilizadas para medir os efeitos dos calcários foram milho e, a seguir, trigo. Os resultados mostraram efeitos idênticos dos dois calcários na produção de massa seca, para as duas culturas. Os aumentos verificados foram grandes, e não foi observada diferença entre os dois materiais corretivos estudados, como também não foram obtidas diferenças de produções com as diversas granulo-metrias empregadas, para os dois calcários.