bluuebunny/crossref_metadata_2025 huggingface dataset:
Genetic Regulation of Glucose Metabolism
Authors: Sutherland Calum , O'Brien Richard , Granner Daryl K.
Published: November 2010

The sections in this article are:

Glucagon and Insulin Action

Signaling from the Cell Membrane to the Nucleus

DNA Elements and Their Binding Proteins

Genetic Regulation of the Hepatic Gluconeogenic Enzymes

Glucose‐6‐Phosphatase

Fructose‐1,6‐Bisphosphatase

Phosphoenolpyruvate Carboxykinase

Genetic Regulation of the Hepatic Glycolytic Enzymes

Glucokinase

6‐Phosphofructo‐1‐Kinase

Pyruvate Kinase

6‐Phosphofructo‐2‐Kinase/Fructose‐2,6‐Bisphosphatase

Genetic Regulation of Other Proteins Involved in Glucose Metabolism

Glyceraldehyde‐3‐Phosphate Dehydrogenase

Tyrosine Aminotransferase

GLUT‐1 Glucose Transporter

Hexokinase II

Genetic Regulation of Lipogenic Enzymes

Acetyl‐CoA Carboxylase

Fatty Acid Synthase

Malic Enzyme

Conclusions and Perspectives
Control of Glucose Production in vivo by Insulin and Glucagon
Authors: Cherrington Alan D.
Published: November 2010

The sections in this article are:

Assessment of Glucose Production in vivo

Glucagon and Glucose Production

Effects of Basal Glucagon

Effects of Increments in Glucagon

Insulin and Glucose Production

Effects of Insulin Deficiency

Effects of Increases in Insulin

Integration of Insulin and Glucagon's Effects
Regulation of Hepatic Glucose Uptake
Authors: Taylor Roy , Shulman Gerald I.
Published: November 2010

The sections in this article are:

Homeostatic Mechanisms

Overview

Insulin

Glucagon

Noninsulin/Glucagon Regulation of Hepatic Glucose Production

Metabolism in the Postprandial State

Overview

Hepatic Glycogen Storage after Eating

Source of Glucose Carbon for Glycogen Synthesis

Modulation of Hepatic Glucose Uptake by a Portal Signal

Turnover of Liver Glycogen Stores

Normal Diurnal Fluctuation in Hepatic Glycogen Content

Effect of Eating on Hepatic Glucose Production

Metabolism in the Postabsorptive State

Overview

Gluconeogenesis

Glycogenolysis

Early Adaptation to Starvation

Nature's Experiments

Glycogen Storage Disease

Diabetes

Cirrhosis

Pregnancy
The Metabolic Actions of Growth Hormone
Authors: Goodman H. Maurice
Published: November 2010

The sections in this article are:

Growth Hormone as a Metabolic Hormone

Historical Background

Growth Hormone and Insulin‐like Growth Factor 1

Biochemical Interrelationships: The Glucose‐Fatty Acid Cycle

Metabolic Effects of Growth Hormone as Revealed in Whole Body Studies

Chronic Long‐Term Effects

Short‐Term Effects of Growth Hormone as Studied in Vivo

Effects of Growth Hormone on Individual Target Tissues

Liver

Muscle

Adipose Tissue

Pancreatic Beta Cells

Unresolved Issues

Does Insulin‐like Growth Factor 1 Mediate the Metabolic Effects of Growth Hormone?

Growth Hormone and Insulin Sensitivity

Do All of the Responses to Growth Hormone Arise from a Single Interaction of Growth Hormone with Its Receptor?

Biological Activities of Growth Hormone Fragments

Summary, Conclusions, and Future Directions
Thyroid Hormone Regulation of Islet Cell Hormone Metabolic Actions
Authors: Clarke Bart L. , Degroot Leslie J.
Published: November 2010

The sections in this article are:

Molecular Actions of Thyroid Hormone

Thyroid Hormone Regulation of Growth and Development

Extrahypothalamic Thyrotropin‐Releasing Hormone

Metabolic Actions of Islet Cell Hormones

Insulin

Glucagon

Amylin

Calcitonin Gene‐Related Peptide

Somatostatin

Pancreatic Polypeptide

Thyroid Hormone Regulation of Insulin Metabolic Actions

Euthyroidism

Hyperthyroidism

Hypothyroidism

Thyroid Hormone Regulation of Glucagon Metabolic Actions

Hyperthyroidism

Hypothyroidism

Thyroid Hormone Regulation of Somatostatin Metabolic Actions

Hyperthyroidism

Hypothyroidism

Thyroid Hormone Regulation of Pancreatic Polypeptide Metabolic Actions

Summary and Conclusions
Effects of Pregnancy on Metabolism
Authors: Diamond Michael P. , Rossi Gabriele
Published: November 2010

The sections in this article are:

Prepregnancy Period

First Trimester

Introduction

Carbohydrate Metabolism

Lipid Metabolism

Protein Metabolism

Second and Third Trimesters

Counterregulation During Pregnancy
The Prevention and Correction of Hypoglycemia
Authors: Cryer Philip E.
Published: November 2010

The sections in this article are:

Systemic Glucose Balance

Postabsorptive State

Postprandial State

Exercise

Other Conditions

Physiological Responses to Hypoglycemia

Hormonal, Neural and Substrate Responses

Symptoms, Cognitive Dysfunction and Signs

Glycemic Thresholds

Impact of Substrates other than Glucose

Physiological Actions of Glucoregulatory Factors

Regulatory Factor: Insulin

Counterregulatory Factors

Integrated Physiology of Glucose Counterregulation

Correction of Hypoglycemia

Prevention of Hypoglycemia

Insight from Pathophysiology

Hierarchy of the Redundant Glucose‐Counterregulatory Factors
Comparison between supervised and unsupervised classifications of neuronal cell types: A case study
Authors: Guerra Luis , McGarry Laura M. , Robles Víctor , Bielza Concha , Larrañaga Pedro , Yuste Rafael
Published: November 2010

In the study of neural circuits, it becomes essential to discern the different neuronal cell types that build the circuit. Traditionally, neuronal cell types have been classified using qualitative descriptors. More recently, several attempts have been made to classify neurons quantitatively, using unsupervised clustering methods. While useful, these algorithms do not take advantage of previous information known to the investigator, which could improve the classification task. For neocortical GABAergic interneurons, the problem to discern among different cell types is particularly difficult and better methods are needed to perform objective classifications. Here we explore the use of supervised classification algorithms to classify neurons based on their morphological features, using a database of 128 pyramidal cells and 199 interneurons from mouse neocortex. To evaluate the performance of different algorithms we used, as a “benchmark,” the test to automatically distinguish between pyramidal cells and interneurons, defining “ground truth” by the presence or absence of an apical dendrite. We compared hierarchical clustering with a battery of different supervised classification algorithms, finding that supervised classifications outperformed hierarchical clustering. In addition, the selection of subsets of distinguishing features enhanced the classification accuracy for both sets of algorithms. The analysis of selected variables indicates that dendritic features were most useful to distinguish pyramidal cells from interneurons when compared with somatic and axonal morphological variables. We conclude that supervised classification algorithms are better matched to the general problem of distinguishing neuronal cell types when some information on these cell groups, in our case being pyramidal or interneuron, is knowna priori. As a spin‐off of this methodological study, we provide several methods to automatically distinguish neocortical pyramidal cells from interneurons, based on their morphologies. © 2010 Wiley Periodicals, Inc. Develop Neurobiol 71: 71–82, 2011
Activity‐dependent changes in the firing properties of neocortical fast‐spiking interneurons in the absence of large changes in gene expression
Authors: Miller Mark N. , Okaty Benjamin W. , Kato Saori , Nelson Sacha B.
Published: November 2010

The diverse cell types that comprise neocortical circuits each have characteristic integrative and firing properties that are specialized to perform specific functions within the network. Parvalbumin‐positive fast‐spiking (FS) interneurons are a particularly specialized cortical cell‐type that controls the dynamics of ongoing activity and prevents runaway excitation by virtue of remarkably high firing rates, a feature that is permitted by narrow action potentials and the absence of spike‐frequency adaptation. Although several neuronal intrinsic membrane properties undergo activity‐dependent plasticity, the role of network activity in shaping and maintaining specialized, cell‐type‐specific firing properties is unknown. We tested whether the specialized firing properties of mature FS interneurons are sensitive to activity perturbations by inactivating a portion of motor cortex in vivo for 48 h and measuring resulting plasticity of FS intrinsic and firing properties with whole‐cell recording in acute slices. Many of the characteristic properties of FS interneurons, including nonadapting high‐frequency spiking and narrow action potentials, were profoundly affected by activity deprivation both at an age just after maturation of FS firing properties and also a week after their maturation. Using microarray screening, we determined that although normal maturation of FS electrophysiological specializations is accompanied by large‐scale transcriptional changes, the effects of deprivation on the same specializations involve more modest transcriptional changes, and may instead be primarily mediated by post‐transcriptional mechanisms. © 2010 Wiley Periodicals, Inc. Develop Neurobiol 71: 62–70, 2011
Interneurons in the developing human neocortex
Authors: Zecevic Nada , Hu Frances , Jakovcevski Igor
Published: November 2010

Cortical interneurons play a crucial role in the functioning of cortical microcircuitry as they provide inhibitory input to projection (pyramidal) neurons. Despite their involvement in various neurological and psychiatric disorders, our knowledge about their development in human cerebral cortex is still incomplete. Here we demonstrate that at the beginning of corticogenesis, at embryonic 5 gestation weeks (gw, Carnegie stage 16) in human, early neurons could be labeled with calretinin, calbindin, and GABA antibodies. These immunolabeled cells show a gradient from the ganglionic eminences (GE) toward the neocortex, suggesting that GE is a well conserved source of early born cortical interneurons from rodents to human. At mid‐term (20 gw), however, a subset of calretinin+ cells proliferates in the cortical subventricular zone (SVZ), suggesting a second set of interneuron progenitors that have neocortical origin. Neuropeptide Y, somatostatin, or parvalbumin cells are sparse in mid‐term cerebral cortex. In addition to the early source of cortical interneurons in the GE and later in the neocortical SVZ, other regions, such as the subpial granular layer, may also contribute to the population of human cortical interneurons. In conclusion, our findings from cryosections and previous in vitro results suggest that cortical interneuron progenitor population is more complex in humans relative to rodents. The increased complexity of progenitors is probably evolutionary adaptation necessary for development of the higher brain functions characteristic to humans. © 2010 Wiley Periodicals, Inc. Develop Neurobiol 71: 18–33, 2011
Cholecystokinin: A multi‐functional molecular switch of neuronal circuits
Authors: Lee Soo Yeun , Soltesz Ivan
Published: November 2010

Cholecystokinin (CCK), a peptide originally discovered in the gastrointestinal tract, is one of the most abundant and widely distributed neuropeptides in the brain. In spite of its abundance, recent data indicate that CCK modulates intrinsic neuronal excitability and synaptic transmission in a surprisingly cell‐type specific manner, acting as a key molecular switch to regulate the functional output of neuronal circuits. The central importance of CCK in neuronal networks is also reflected in its involvement in a variety of neuropsychiatric andneurological disorders including panic attacks and epilepsy. © 2010 Wiley Periodicals, Inc. Develop Neurobiol 71: 83–91, 2011
Origins of neocortical interneurons in mice
Authors: Welagen Jelle , Anderson Stewart
Published: November 2010

GABAergic interneurons influence the development and function of the cerebral cortex through the actions of a variety of subtypes. Despite the relevance to cortical function and dysfunction, including seizure disorders and neuropsychiatric illnesses, the molecular determinants of interneuron fate remain largely unidentified. Challenges to this endeavor include the difficulty of studying fate determination of cells that even in rodents do not fully mature until weeks after their embryonic birth. However, in recent years a strong literature has grown on the temporal and spatial origins of distinct interneuron groups and types. Here we seek to highlight these findings, particularly in mice. Our goal is to lay the groundwork for future studies that use mouse genetics to study cortical interneuron fate determination and function. © 2010 Wiley Periodicals, Inc. Develop Neurobiol 71: 10–17, 2011
Migration and ramification of microglia in quail embryo retina organotypic cultures
Authors: Carrasco Maria‐Carmen , Navascués Julio , Cuadros Miguel A. , Calvente Ruth , Martín‐Oliva David , Santos Ana M. , Sierra Ana , Ferrer‐Martín Rosa M. , Marín‐Teva José L.
Published: November 2010

Organotypic cultures of retina explants preserve the complex cellular microenvironment of the retina and have been used as a tool to assess the biological functions of some cell types. However, studies to date have shown that microglial cells activate quickly in response to the retina explantation. In this study, microglial cells migrated and ramified in quail embryo retina organotypic cultures (QEROCs) according to chronological patterns bearing a resemblance to those in the retina in situ, despite some differences in cell density and ramification degree. Retinal explants from quail embryos at 9 days of incubation (E9) proved to be the best in vitro system for reproducing a physiological‐like behavior of microglial cells when cultured in Eagle's basal medium supplemented with horse serum. During the first week in vitro, microglial cells migrated tangentially in the vitreal part of QEROCs, and some began to migrate radially from 3 days in vitro (div) onward, ramifying in the inner and outer plexiform layers, thus mimicking microglia development in the retina in situ, although reaching a lower degree of ramification after 7 div. From 8 div onward, microglial cells rounded throughout the explant thickness simultaneously with the nonphysiological appearance of dead photoreceptors and round microglia in the outernuclear layer. Therefore, E9 QEROCs can be used during the first week in vitro as a model system for experimental studies of molecules putatively involved in microglial migration and ramification. © 2010 Wiley Periodicals, Inc. Develop Neurobiol 71: 296–315, 2011
High‐frequency and adaptive‐like dynamics of human CD1 self‐reactive T cells
Authors: de Lalla Claudia , Lepore Marco , Piccolo Francesco M. , Rinaldi Anna , Scelfo Andrea , Garavaglia Claudio , Mori Lucia , De Libero Gennaro , Dellabona Paolo , Casorati Giulia
Published: November 2010

CD1 molecules present lipid antigens to T cells. An intriguing subset of human T cells recognize CD1‐expressing cells without deliberately added lipids. Frequency, subset distribution, clonal composition, naïve‐to‐memory dynamic transition of these CD1 self‐reactive T cells remain largely unknown. By screening libraries of T‐cell clones, generated from CD4+ or CD4−CD8− double negative (DN) T cells sorted from the same donors, and by limiting dilution analysis, we find that the frequency of CD1 self‐reactive T cells is unexpectedly high in both T‐cell subsets, in the range of 1/10–1/300 circulating T cells. These T cells predominantly recognize CD1a and CD1c and express diverse TCRs. Frequency comparisons of T‐cell clones from sorted naïve and memory compartments of umbilical cord and adult blood show that CD1 self‐reactive T cells are naïve at birth and undergo an age‐dependent increase in the memory compartment, suggesting a naïve/memory adaptive‐like population dynamics. CD1 self‐reactive clones exhibit mostly Th1 and Th0 functional activities, depending on the subset and on the CD1 isotype restriction. These findings unveil the unanticipated relevance of self‐lipid T‐cell response in humans and clarify the basic parameters of the lipid‐specific T‐cell physiology.
4‐Aminothioureaprolinal Dithioacetal as a Catalyst for Highly Enantioselective Michael Additions of Ketones and Aldehydes to Nitroolefins
Authors: Chuan Yong‐Ming , Yin Li‐Yang , Zhang Yan‐Mei , Peng Yun‐Gui
Published: November 2010

4‐Aminothioureaprolinal dithioacetal 4a is a highly efficient catalyst for the asymmetric Michael addition of ketones and aldehydes to nitroolefins requiring only 3 mol‐% catalyst loading. The reactions proceeded smoothly and gave syn selective adducts with excellent yields (up to 98 % yield), diastereoselectivity (up to >99:1 dr), and enantioselectivity (up to 99 % ee) under solvent free conditions at room temperature. This extremely simple and practical procedure increases the attractiveness of this reaction.
Capacitively coupled contactless conductivity detection for microseparation techniques – recent developments
Authors: Kubáň Pavel , Hauser Peter C.
Published: November 2010

An overview of the developments of capacitively coupled contactless conductivity detection in CE and related techniques over approximately the last 2 years is given. The method has seen strong growth, and diverse new applications are being reported. Besides more advanced techniques on conventional capillaries, these include further developments of detection on lab‐on‐chip devices as well as in miniaturized chromatographic systems and some methods not involving separations. An increasing number of reports are based on the now readily available commercial detectors, but, while few publications on fundamental studies have appeared recently, interesting new approaches on creating low cost devices have also appeared.
Navier–Stokes and Lattice–Boltzmann on octree‐like grids in the Peano framework
Authors: Mehl M. , Neckel T. , Neumann Ph.
Published: November 2010

The Navier–Stokes equations (NS) and the Lattice–Boltzmann method (LBM) are the main two types of models used in computational fluid dynamics yielding similar results for certain classes of flow problems both having certain advantages and disadvantages.

We present the realization of both approaches—laminar incompressible NS and LB—on the same code basis, our PDE framework Peano. Peano offers a highly memory efficient implementation of all grid and data handling issues for structured adaptive grids. Using a common code basis allows to compare NS and LB without distorting the results by differences in the maturity and degree of hardware‐optimality of the technical implementation.

In addition to a comparison for some test examples, we briefly present the coupling of NS and LB in one single simulation. Such a coupling might be useful to simulate boundary effects happening on a smaller scale more accurately with LB but still using NS in the main part of the domain. Copyright © 2010 John Wiley & Sons, Ltd.
Incompact3d: A powerful tool to tackle turbulence problems with up to O(105) computational cores
Authors: Laizet Sylvain , Li Ning
Published: November 2010

Understanding the nature of complex turbulent flows remains one of the most challenging problems in classical physics. Significant progress has been made recently using high performance computing, and computational fluid dynamics is now a credible alternative to experiments and theories in order to understand the rich physics of turbulence. In this paper, we present an efficient numerical tool called Incompact3d that can be coupled with massive parallel platforms in order to simulate turbulence problems with as much complexity as possible, using up to O(105) computational cores by means of direct numerical simulation (DNS). DNS is the simplest approach conceptually to investigate turbulence, featuring the highest temporal and spatial accuracy and it requires extraordinary powerful resources. This paper is an extension of Laizet et al.(Comput. Fluids 2010; 39(3):471–484) where the authors proposed a strategy to run DNS with up to 1024 computational cores. Copyright © 2010 John Wiley & Sons, Ltd.
Neighbour lists in smoothed particle hydrodynamics
Authors: Domínguez J. M. , Crespo A. J. C. , Gómez‐Gesteira M. , Marongiu J. C.
Published: November 2010

Since smoothed particle hydrodynamics (SPH) is based on interactions with the closer neighbouring particles, implementing the neighbour list is a key point in terms of the high performance of the code. The efficiency of the method depends directly on how to build and use the neighbour list. In the present work, the available searching algorithms for SPH codes are analyzed. Different gridding algorithms are evaluated, the gains in efficiency obtained from reordering of particles is investigated and the cell‐linked list and Verlet list methods are studied to create the neighbour list. Furthermore, an innovative searching procedure based on a dynamic updating of the Verlet list is proposed. The efficiency of the algorithms is analyzed in terms of computational time and memory requirements. Copyright © 2010 John Wiley & Sons, Ltd.
Volatility spillover effects and cross hedging in corn and crude oil futures
Authors: Wu Feng , Guan Zhengfei , Myers Robert J.
Published: November 2010

Using a volatility spillover model, we find evidence of significant spillovers from crude oil prices to corn cash and futures prices, and that these spillover effects are time‐varying. Results reveal that corn markets have become much more connected to crude oil markets after the introduction of the Energy Policy Act of 2005. Furthermore, when the ethanol–gasoline consumption ratio exceeds a critical level, crude oil prices transmit positive volatility spillovers into corn prices and movements in corn prices are more energy‐driven. Based on this strong volatility link between crude oil and corn prices, a new cross‐hedging strategy for managing corn price risk using oil futures is examined and its performance is studied. Results show that this cross‐hedging strategy provides only slightly better hedging performance compared with traditional hedging in corn futures markets alone. The implication is that hedging corn price risk in corn futures markets alone can still provide relatively satisfactory performance in the biofuel era. © 2010 Wiley Periodicals, Inc. Jrl Fut Mark
Protectiveness of water quality criteria for copper in western United States waters relative to predicted olfactory responses in juvenile Pacific salmon
Authors: DeForest David K. , Gensemer Robert W. , Van Genderen Eric J. , Gorsuch Joseph W.
Published: November 2010

Copper (Cu) can impair olfaction in juvenile Pacific salmon (as well as other fishes), thus potentially inhibiting the ability of juveniles to avoid predators or to find food. Because Cu is commonly elevated in stormwater runoff in urban environments, storm events may result in elevated Cu concentrations in salmon-bearing streams. Accordingly, there is concern that existing Cu criteria, which were not derived using data for olfactory-related endpoints, may not be adequately protective of juvenile salmon. However, a modification of the US Environmental Protection Agency (USEPA) biotic ligand model (BLM) for deriving site-specific Cu criteria was recently proposed, which accounted for the sensitivity of olfactory endpoints. The modification was based on olfactory inhibition in juvenile coho salmon (Oncorhynchus kisutch) exposed to Cu in various combinations of pH, hardness, alkalinity, and dissolved organic carbon (DOC) concentrations. We used that olfactory-based BLM to derive 20% inhibition concentrations (IC20) values for Cu for 133 stream locations in the western United States. The olfactory BLM-based IC20 values were compared to the existing hardness-based Cu criteria and the USEPA's BLM-based Cu criteria for these representative natural waters of the western United States. Of the 133 sampling locations, mean hardness-dependent acute and chronic Cu criteria were below the mean olfactory-based BLM IC20 value in 122 (92%) and 129 (97%) of the waters, respectively (i.e., <20% olfactory impairment would have been predicted at the mean hardness-based Cu criteria concentrations). Waters characterized by a combination of high hardness and very low DOC were most likely to have hardness-based Cu criteria that were higher than the olfactory-based BLM IC20 values, because DOC strongly influences Cu bioavailability in the BLM. In all waters, the USEPA's current BLM-based criteria were below the mean olfactory-based BLM IC20 values, indicating that the USEPA's BLM-based criteria are protective of olfactory impairment in juvenile salmon. Integr Environ Assess Manag 2011;7:336–347. © 2011 SETAC
Intake of n‐3 and n‐6 polyunsaturated fatty acids and development of colorectal cancer by subsite: Japan Public Health Center–based prospective study
Authors: Sasazuki Shizuka , Inoue Manami , Iwasaki Motoki , Sawada Norie , Shimazu Taichi , Yamaji Taiki , Takachi Ribeka , Tsugane Shoichiro ,   for the Japan Public Health Center–Based Prospective Study Group
Published: November 2010

To date, epidemiologic studies investigating intake of n‐3 and n‐6 polyunsaturated fatty acids and risk of colorectal cancer are limited, and results remain inconsistent. This is the first prospective study to show the association by subsite (proximal colon, distal colon, rectum). To clarify the role of n‐3 and n‐6 polyunsaturated fatty acids intake in colon carcinogenesis, we conducted a large, population‐based prospective study, characterized by high fish consumption and a wide range of n‐3 polyunsaturated fatty acids intakes. Subjects were followed from response to a lifestyle questionnaire in 1995–1999 through 2006. During 827,833 person‐years of follow‐up (average 9.3 years), we identified 1,268 new colorectal cancer cases (521 colon and 253 rectal for men; 350 colon and 144 rectal for women). Compared to the lowest quintile, the relative risk and 95% confidence interval of developing cancer among the fifth quintile of marine n‐3 polyunsaturated fatty acids intake were 0.60 and 0.31–1.14, respectively (p for trend = 0.04) in the colon in women and 0.35 and 0.14–0.88 (p for trend = 0.05) and 1.82 and 0.79–4.20 (p for trend = 0.16) in the proximal and distal colon, respectively, in men. For rectal cancer, the dose response for marine n‐3 polyunsaturated fatty acids s was unclear; rather, we observed U‐shaped associations in men and women. We found no evidence that n‐6 polyunsaturated fatty acids increases or the n‐3/n‐6 ratio decreases the risk of colorectal cancer. Our results suggest that intake of marine n‐3 polyunsaturated fatty acids may be inversely related to the risk of cancer in the proximal site of the large bowel.
Hydraulic Microdistribution of Cased Caddis Larvae in an Austrian Mountain Brook
Authors: Bacher I. , Waringer J. A.
Published: November 2010

Water velocity acting at the upper edge of the case opening was measured at the locations of 1074 cased caddis larvae along a cross section of the Seebach near Lunz Biological Station (Lower Austria). In addition, Froude number, boundary Reynolds number, bottom shear stress and thickness of the viscous sublayer were measured at the center of contagious sampling squares of 30 × 30 cm over the same cross section. Measurements were made at monthly intervals from 2 November 1993 to 24 October 1994 using an impeller‐meter (Ott C2; propeller diameter = 30 mm) and a set of FST hemispheres. A total of 16 species was recorded with Drusus biguttatus Pictet, Allogamus auricollis Pictet and Potamophylax cingulatus Stephens being most abundant. Maximum values of current velocity and hydraulic stress parameters (e.g. Froude numbers up to 0.90) were recorded for D. biguttatus. P. cingulatus and Glossosoma conformis Neboiss, whereas lowest values of hydraulic stress parameters were observed in Sericostoma flavicorne Schneider. In addition, up to 40% of the population in Drusinae species and P. cingulatus was over‐represented in high stress areas at the streambed, whilst up to 36% of the population in S. flavicorne and Allogamus spp. were over‐represented in low stress areas.
Effects of Aufwuchs on Colonization by Simuliids (Simuliidae, Diptera)
Authors: Kiel Ellen
Published: November 2010

While different studies investigated effects of surface properties on the adhesion and population dynamics of marine sessile organisms (Balanidae, Bryozoa etc.), little is known about sedentary freshwater macroinvertebrates. Artificial substrates were used to investigate the effects of Aufwuchs on density and distribution of colonizing blackfly larvae and pupae. Although, settlement of blackfly larvae often is said to be impeded by Aufwuchs or siltation, they colonized both bare substrates and those on which a thick Aufwuchs cover had developed. Often no differences in density appeared on substrates exposed for less than 6‐9 d. Thus Aufwuchs apparently does not prevent initial settling of larvae. However, simuliid densities on Aufwuchs covered substrates declined after several more days of exposure, suggesting that surface properties may affect long‐term settlement.
Polychaete Distribution on the Chatham Rise, Southwest Pacific
Authors: Probert P. Keith , Grove Simon L. , McKnight Don G. , Read Geoffrey B.
Published: November 2010

Macrobenthic samples Were collected along 3 north‐south transects at 244‐1394 m depth across the Chatham Rise, eastern New Zealand, to examine the distribution of polychaete assemblages in the region of the Subtropical Convergence (STC). Two main assemblages were identified: at 244‐663 m depth occurring mainly on the crest of the Rise, and at 802‐1394 m on the slopes of the Rise. Community composition differed., however, between the northern and southern slopes of the Rise. The southern slope supported higher faunal densities and a greater proportion of surface deposit feeders. This latitudinal difference may reflect variability in organic flux across the STC.
Two New Species of Rotifera from China
Authors: Zhugex Yan , Koste Walter
Published: November 2010

Two new rotifera species,Brachionus huangin. sp. andLecane chinesensisn. sp. are described and illustrated from different localities in China. The main distinguishing taxonomic features ofB. huangiare three pairs of apical spines, a pair of symmetrical caudal spines and a wide caudal projection. ForL. chinesensis, the main characteristics are the two‐sided small extentions of the foot pseudosegment, the long and innercurved apical spines and ventral lorica anteriorly narrower than the dorsal one.
A convenient synthesis of 2′,3′‐dideoxyinosine‐13C5 and related 2′,3′‐dideoxyadenosine‐13C5
Authors: Ekhato I. Victor , Rinehart Jay K.
Published: November 2010

2′,3′‐Dideoxyinosine‐13C5 (ddI‐13C5) and the related 2′,3′‐dideoxyadenosine‐13C5 (ddA‐13C5) were prepared from (S)‐5‐[13C5]2,3‐dideoxyribonolactone 1. From a batch of this starting material ddI‐13C5 was made in 27% overall yield in seven steps and ddA‐13C5 in five steps and 14% overall yield. The known synthesis of ddI‐13C5 from glucose‐13C6 took 18‐steps; therefore the present work is a substantial improvement. Copyright © 2010 John Wiley & Sons, Ltd.
Synthesis and biological evaluation of 125I/123I‐labelled analogues of citalopram and escitalopram as potential radioligands for imaging of the serotonin transporter
Authors: Madsen Jacob , Elfving Betina , Frokjaer Vibe G. , Kornum Birgitte R. , Thomsen Gerda , Martiny Lars , Knudsen Gitte M.
Published: November 2010

Two novel radioligands for the serotonin transporter (SERT), [125I]{3‐[5‐iodo‐1‐[4‐fluorophenyl)‐1,3‐dihydroisobenzofuran‐1‐yl]‐propyl}‐dimethylamine ([125I]‐2) and S‐[125I]{3‐[5‐iodo‐1‐(4‐fluorophenyl)‐1,3‐dihydroisobenzofuran‐1‐yl]‐propyl}‐dimethylamine ([125I]‐(S)‐2) were synthesized in a Br/125I exchange reaction. Binding experiments in rats yielded Kd values of 0.7 ± 0.06 and 0.52 ± 0.02 nM for [125I]‐2 and [125I]‐(S)‐2, respectively. One hour after intravenous injection of [125I]‐2, 0.34% of the injected dose had accumulated in the brain. The highest hypothalamus‐to‐cerebellum ratio was reached 2 h after injection of [125I]‐(S)‐2 and amounted to 2.4. Pre‐treatment experiments with paroxetine resulted in effective reduction of the target‐to‐cerebellum ratios.

The corresponding iodine‐123 labelled compound S‐[123I]{3‐[5‐Iodo‐1‐(4‐fluorophenyl)‐1,3‐dihydroisobenzofuran‐1‐yl]‐propyl}‐dimethylamine [123I]‐S‐2 was investigated in a pig single photon emission computed tomography (SPECT) study. Between 60 and 110 min after IV injection, the midbrain‐to‐cerebellum ratio was 1.2. However, the uptake did not differ between high‐density and medium‐density regions questioning the feasibility of the radioligand in imaging cortical SERT distribution in vivo.

These data suggest that the iodine‐labelled derivatives of citalopram and escitalopram are not superior to another SPECT tracer for the SERT, namely [123I]ADAM. Copyright © 2010 John Wiley & Sons, Ltd.
Synthesis of 3H‐, 13C3‐, and 14C‐labeled Sch 727965
Authors: Lavey C. Flader , Hesk D. , Koharski D. , Truong V. , McNamara P.
Published: November 2010

The preparation of [3H]Sch 727965 from unlabeled compound and tritiated water was base catalyzed. Diethyl [13C3]malonate was used to prepare [13C3]Sch 727965 in five steps in 21.8% overall yield. In a similar manner, [14C]Sch 727965 was prepared in five steps from diethyl [2‐14C]malonate in 11.1% radiochemical yield. Copyright © 2010 John Wiley & Sons, Ltd.
Electron beam welding of titanium aluminides – Influence of the welding parameters on the weld seam and microstructure
Authors: Reisgen U. , Olschok S. , Backhaus A.
Published: November 2010

This paper gives an account of research which has been carried out on electron‐beam welded specimens made of high‐Niobium γ/α2‐titanium aluminides in comparison to γ‐titanium aluminides. The high niobium content of this alloy (5–8%) has a positive effect on the strength and the creep resistance and also on the oxidation resistance. The standard welding parameters weld speed and beam current and also additional beam oscillation have been used for the determination of factors which will effect the solidification morphology and structural constitution since those, in return, exert influence on the high cracking susceptibility of the alloy. In order to reduce the critical cooling rate, preheating which has a positive effect on crack formation has, in addition, been applied. In a direct comparison of both alloys, micrographs and electron beam micro‐analyses of the developing weld structure and of the heat affected zone, the effects of the beam parameters on both alloys have been established.

Diese Veröffentlichung berichtet über Untersuchungen an Elektronenstrahl geschweißten Proben aus hochniobhaltigen γ/α2‐Titan‐Aluminiden im Vergleich zu γ‐Titan‐Aluminiden. Der hohe Niobgehalt dieser Legierung von 5–8% wirkt sich positiv auf die Festigkeit und Kriechbeständigkeit sowie die Oxidationsbeständigkeit aus. Anhand der Standard‐Schweißparameter Schweißgeschwindigkeit und Strahlstrom sowie zusätzlicher Strahlpendelung werden Einflussfaktoren auf die Erstarrungsmorphologie und Gefügeausbildung bestimmt, die die hohe Rissanfälligkeit der Legierung beeinflussen. Zusätzlich wird eine Vorwärmung zur Reduzierung der kritischen Abkühlrate appliziert, die günstig auf die Rissvermeidung einwirkt. Im direkten Vergleich der zwei Legierungen werden durch Schliffbilder und Elektronenstrahlmikroanalysen des entstehenden Schweißgefüges und der Wärmeeinflusszone Auswirkungen der Strahlparameter auf die beiden Legierungen festgestellt.
Resistance spot welding and weldbonding of advanced high strength steels
Authors: Weber G. , Thommes H. , Gaul H. , Hahn O. , Rethmeier M.
Published: November 2010

The resistance spot welding procedure is one of the most important joining techniques in lightweight car body shell mass production. Especially for newly developed high strength multiphase steels, also called advanced high strength steels (AHSS), and ultra high strength steels (UHSS), this joining technique has more advantages than other thermal and mechanical joining procedures for thin steel sheets. Additionally, the technique of adhesive bonding and its combination with the technique of resistance spot welding called weldbonding becomes more and more important. One of the targets of the contribution is to show the influence of joined advanced high strength steels on the process reliability for both the resistance spot welding process and the weldbonding process. Based on welding current ranges and on results of electrode wear tests, statements concerning the resistance spot weldability of some special AHSS will be given. The mechanical behaviour of spot welded and weldbonded joints for different AHSS will be studied. Furthermore, some statements regarding the fracture behaviour, the hardness and the fatigue behaviour of both spot welded and weldbonded joints for different AHSS will be given. Finally, some results on the mechanical properties of spot welded and weldbounded joints under corrosive attacks with be discused.

Widerstandspunktschweißen ist die am häufigsten eingesetzte Fügetechnik in der Massenfertigung von Rohkarosserien. Insbesondere beim Einsatz von neuentwickelten, hochfesten Mehrphasenstählen, auch Advanced High Strength Steels (AHSS) genannt, und Ultra hochfesten Stählen (UHSS) hat das Widerstandspunktschweißen eindeutige Vorzüge gegenüber anderen, thermischen oder mechanischen, Fügetechniken für Feinbleche. Darüberhinaus gewinnt das Kleben und die Kombination des Klebens mit dem Widerstandspunktschweißen, Punktschweißkleben genannt, zunehmend an Bedeutung. Ein Ziel dieses Beitrags ist es, den Einfluss der gefügten hochfesten Stähle auf die Prozesssicherheit sowohl des Widerstandspunktschweißprozesses als auch des Punktschweißklebprozesses zu zeigen. Anhand der Schweißbereichsdiagramme und der Ergebnisse von Standmengenversuchen werden Aussagen zur Widerstandspunktschweißeignung einiger besonderer AHSS getroffen. Die mechanischen Eigenschaften von punktgeschweißten und punktschweißgeklebten Verbindungen aus verschiedenen AHSS und UHSS werden untersucht. Darüberhinaus werden noch einige Aussagen zum Bruchverhalten, zur Härte und zur Ermüdungsfestigkeit sowohl der punktgeschweißten als auch der punktschweißgeklebten Verbindungen für verschiedene AHSS getroffen. Abschließend werden einige Ergebnisse zum mechanischen Verhalten punktgeschweißter und punktschweißgeklebter Verbindungen in korrosiver Umgebung diskutiert.
Spatially quantifying microscopic tumor invasion and proliferation using a voxel‐wise solution to a glioma growth model and serial diffusion MRI
Authors: Ellingson Benjamin M. , LaViolette Peter S. , Rand Scott D. , Malkin Mark G. , Connelly Jennifer M. , Mueller Wade M. , Prost Robert W. , Schmainda Kathleen M.
Published: November 2010

The purpose of this study was to develop a voxel‐wise analytical solution to a glioma growth model using serial diffusion MRI. These cell invasion, motility, and proliferation level estimates (CIMPLE maps) provide quantitative estimates of microscopic tumor growth dynamics. After an analytical solution was found, noise simulations were performed to predict the effects that perturbations in apparent diffusion coefficient values and the time between apparent diffusion coefficient map acquisitions would have on the accuracy of CIMPLE maps. CIMPLE maps were then created for 53 patients with gliomas with WHO grades of II–IV. MR spectroscopy estimates of the choline‐to‐N‐acetylaspartate ratio were compared to cell proliferation estimates in CIMPLE maps using Pearson's correlation analysis. Median differences in cell proliferation and diffusion rates between WHO grades were compared. A strong correlation (R2 = 0.9714) and good spatial correspondence were observed between MR spectroscopy measurements of the choline‐to‐N‐acetylaspartate ratio and CIMPLE map cell proliferation rate estimates. Estimates of cell proliferation and diffusion rates appear to be significantly different between low‐ (WHO II) and high‐grade (WHO III–IV) gliomas. Cell diffusion rate (motility) estimates are highly dependent on the time interval between apparent diffusion coefficient map acquisitions, whereas cell proliferation rate estimates are additionally influenced by the level of noise present in apparent diffusion coefficient maps. Magn Reson Med, 2010. © 2010 Wiley‐Liss, Inc.
“PINOT”: Time‐resolved parallel magnetic resonance imaging with a reduced dynamic field of view
Authors: Hamilton Lei Hou , Fabregat Javier Acebron , Moratal David , Ramamurthy Senthil , Lerakis Stamatios , Parks W. James , Sallee Denver , Brummer Marijn E.
Published: November 2010

This article introduces a novel method named “Parallel Imaging and Noquist in Tandem” (PINOT) for accelerated image acquisition of cine cardiac magnetic resonance imaging. This method combines two prior information formalisms, the SPACE‐RIP implementation of parallel imaging and the Noquist method for reduced‐data image reconstruction with prior knowledge of static and dynamic regions in the field of view. The general theory is presented, and supported by results from experiments using time‐resolved two‐dimensional simulation data and retrospectively sub‐sampled magnetic resonance imaging data with acceleration factors around 4. A signal‐to‐noise ratio analysis and a comparison study with TSENSE and k‐t SENSE show that PINOT performs favorably in preserving edge detail, at a cost in signal‐to‐noise ratio and computational complexity. Magn Reson Med, 2010. © 2010 Wiley‐Liss, Inc.
Influence of cell cycle phase on apparent diffusion coefficient in synchronized cells detected using temporal diffusion spectroscopy
Authors: Xu Junzhong , Xie Jingping , Jourquin Jerome , Colvin Daniel C. , Does Mark D. , Quaranta Vito , Gore John C.
Published: November 2010

The relationship between the apparent diffusion coefficient of tissue water measured by MR methods and the physiological status of cells is of particular relevance for better understanding and interpretation of diffusion‐weighted MRI. In addition, there is considerable interest in developing diffusion‐dependent imaging methods capable of providing novel information on tissue microstructure, including intracellular changes. To this end, both the conventional pulsed gradient spin–echo methods and the oscillating gradient spin–echo method, which probes diffusion over very short distance (<<cell size) and time scales, were used to measure apparent diffusion coefficient of synchronized packed HL‐60 cells at 7 T. The results show that the pulsed gradient spin–echo method with relatively long diffusion times does not detect changes in apparent diffusion coefficient when structural variations arise during cell division. On the contrary, the oscillating gradient spin–echo method can detect and quantify major changes in intracellular organization that occur during mitosis by appropriate choice of gradient frequency. Cell structural parameters, including cell size, intracellular diffusion coefficient, and surface‐to‐volume ratio were also obtained by fitting the oscillating gradient spin–echo data to simple analytical models. These oscillating gradient spin–echo features may be used in diffusion‐weighted MRI to create parametric maps that may be useful for detecting cancer or changes caused by treatment. Magn Reson Med, 2010. © 2010 Wiley‐Liss, Inc.
A simple approach for three‐dimensional mapping of baseline cerebrospinal fluid volume fraction
Authors: Qin Qin
Published: November 2010

A simple method of measuring baseline cerebrospinal fluid volume fraction (VCSF) in three‐dimensional is proposed that used the characteristic of cerebrospinal fluid with very long T2. It is based on the fitting of monoexponential decay of only cerebrospinal fluid signal, using a nonselective T2 preparation scheme. Three‐dimensional gradient‐ and spin‐echo acquisition also improves signal‐to‐noise ratio efficiency and brain coverage. Both VCSF and T2,CSF are fitted voxel by voxel and analyzed in different cortical areas across subjects. VCSF is largely regionally dependent (occipital: 8.9 ± 1.7%, temporal: 11.4 ± 2.4%, and frontal: 21.4 ± 6.9%). Measured T2,CSF was 1573 ± 146 msec within cortical lobes as compared with 2062 ± 37 msec from ventricle regions. Different parameter set were compared, and the robustness of the new method is demonstrated. Conversely, when comparing with the proposed approach, large overestimation of segmentation based method using T1‐weighted images is found, and the underlying causes are suggested. Magn Reson Med, 2011. © 2010 Wiley‐Liss, Inc.
Kleine Poren — große Wirkung
Authors: Fischer Michael , Sartor Michael , Fröba Michael
Published: November 2010

Metallorganische Gerüstverbindungen eignen sich dazu, Stoffgemische zu trennen und zu reinigen. Neben der Trennung von Gasen wird in jüngerer Zeit zunehmend auch die Trennung von Flüssigkeiten untersucht.
Als Quereinsteiger im Berufsschuldienst
Authors: Schwarz‐Verhoefen Brian
Published: November 2010

Berufliche Schulen stellen viele Quereinsteiger als Lehrer ein — vor allem für wissenschaftliche Fächer. Chemiker, die gerne Wissen vermitteln, sind hier richtig.
Eine Wirtschaftschemikerin in Dubai
Authors: Marcinowski Alice
Published: November 2010

Es begann mit einem Praktikum während des Studiums, dann folgte die Diplomarbeit bei dem internationalen Konsumgüterhersteller Reckitt Benckiser Arabia. Seit April 2009 ist Alice Marcinowski dort als Qualitätsmanagerin zuständig für die Region Naher Osten und Nordafrika.
Chemie und Chemiedidaktik in Äthiopien
Authors: Barke Hans‐Dieter , Harsch Günther
Published: November 2010

Seit zehn Jahren engagieren sich Chemiedidaktiker aus Münster für die Chemikerausbildung in Afrika, denn eine gute naturwissenschaftliche Ausbildung ist essenziell für eine positive Entwicklung.
Die nächste Generation der Point‐of‐care‐Systeme
Authors: Ritzi‐Lehnert Marion
Published: November 2010

Personalisierte Medizin hilft, ineffektive Therapien zu vermeiden, und senkt so Nebenwirkungen und Kosten. Neue, chipbasierte und patientennahe Labordiagnostik weist Grippeviren nach und detektiert Tumorzellen — auch in äußerst geringen Konzentrationen.
Leichte Proteine schwingen besser
Authors: Strasser Ralf , Niemax Jens , Hampel Paul , Rant Ulrich
Published: November 2010

Eine neue chipbasierte Messmethode detektiert Proteine und bestimmt gleichzeitig deren Größe — labelfrei und in Echtzeit.
Tragbares Massenspektrometer für die Analytik vor Ort
Authors: Berchtold Christian
Published: November 2010

Ein mobiler Prototyp ermittelt beispielsweise den Melamingehalt von Milch, und zwar mit hoher Empfindlichkeit, Selektivität und Geschwindigkeit, aber ohne Probenvorbereitung. Neue Ionisierungsmethoden und mobile Ionenfallen unterstützen womöglich bald die Lebensmittelhersteller.
Methoden zur Bestimmung der antioxidativen Aktivität
Authors: Rohn Sascha , Cämmerer Bettina , Kroh Lothar W.
Published: November 2010

Je niedriger die antioxidative Aktivität von Erdnüssen ist, desto schneller verderben sie. Die Elektronenspinresonanzspektroskopie erfasst den Gehalt von antioxidativen Substanzen eines Lebensmittels und sagt so die Lagerfähigkeit der Produkte voraus.
Schnelle Fettextraktion
Authors: Szesniak Ulrich , Holters Marina , Kurowski Christel
Published: November 2010

Nährwertkennzeichnungen informieren etwa über den Fettgehalt eines Frischkäses. Für die Analyse sind die Fette zuvor aus den Lebensmitteln zu extrahieren. Dabei hilft ein Extraktionsgerät von Büchi.
Chemische Risiken in Lebensmitteln
Authors: Grob Konrad
Published: November 2010

Eine riesige Zahl von Chemikalien gelangt in die Lebensmittel, wenn diese verarbeitet oder gelagert werden. Es ist anzunehmen, dass einige der Substanzen gesundheitliche Schäden verursachen. Da die Risiken vermutlich vor allem von den unkontrollierten Stoffe ausgehen, sollte die Lebensmittelüberwachung mehr Ressourcen für die Suche nach diesen Substanzen aufwenden.
Was die Analytik über Blatt und Bohne verrät
Authors: Engelhardt Ulrich H.
Published: November 2010

Wann ist ein Tee schwarz und wann ist er grün? Das zeigt der Catechingehalt. Doch nicht immer ist die Antwort eindeutig. Bei Tee und Kaffee bleiben für den analytischen Chemiker noch viele Rätsel zu lösen.
HPLC auf der Technoparty
Authors: Allemann Daniel , Pauli Hans , Mürner André , Steiner Samuel , Helmlin Hans‐Jörg
Published: November 2010

Seit 1998 analysiert das mobile Labor des Kantonsapothekeramts Bern Partydrogen vor Ort: Über 1700 Proben an mehr als 100 Events haben die Pharmazeuten gemessen. Indem das Labor Jugendliche neugierig macht und neue Trends erfasst, hilft es bei Projekten zur Drogenprävention.