julilili42/papers huggingface dataset:
Low energy focused ion beam system design
2006-07-01

Focused ion beam (FIB) systems operated at typically 30keV energy have now reached a remarkable level of sophistication in terms of optical performance. Not unlike the much earlier developments in scanning electron microscopy, there now seems to be a fairly recent trend towards also enhancing the low energy performance of these systems—mainly driven by their possible utilization in transmission electron microscopy sample preparation. However, low energy operation indeed appears to have already been an issue in the very early days of FIB development—although then against the background of potential applications in direct semiconductor device fabrication. In this study, different approaches for generating low energy ion probes are discussed on the basis of previous and existing FIB systems for which experimental data have been made available. Subsequently, a dedicated low energy focused ion beam column design is introduced, which operates similarly to many modern field emission scanning electron microscopes. The performance of the system is assessed by means of standard aberration-optical calculations as well as by using data from direct ray tracing. The latter also allows the consideration of the impact of mutual Coulomb interactions.
Test of the dual‐belief system in women with and without phobic fear of spiders: a pilot study
2006-07-01

Abstract This study tests the so‐called dual‐belief systems. According to this concept, patients with phobia foster two conflicting peripheral beliefs (situational dependent) about the fear‐inducing stimulus. The existence of such conflicting beliefs can only be explained by so‐called bridging core beliefs. These bridging core beliefs are situation independent and integrate the contradictions of the peripheral beliefs. To test the existence of bridging core beliefs, 60 women with and without spider phobia were interviewed during exposition to phobic and neutral stimuli. Women with phobic anxiety reported more phobic emotions, thoughts, and peripheral beliefs during exposure to a phobic stimulus than during exposure to a neutral stimulus. In core beliefs no differences between the two conditions were found. In the non‐phobic control group, no differences were found for the conditions in any of the dependent variables. All together, these data provide support for the existence of dual‐belief systems as well as bridging core beliefs. Copyright © 2006 John Wiley &amp; Sons, Ltd.
Applicability of an Electrosurgical Device Based on Electromagnetics in Neurosurgery
2006-07-01

Because of electrical and thermal spread to healthy nervous tissue, the application of electrosurgical tools in neurosurgery has specific limitations. This is true for both bipolar and monopolar devices. These limitations are not inherent to an instrument in which action is based on electromagnetic interaction with human tissue. We evaluated the indications and the clinical applicability of a new radiofrequency electrosurgical unit that works on this biophysical principle. The system was found to be a useful addition for the resection of morphologically tougher tissue with keyhole approaches in which the ultrasound aspirator cannot easily be applied.
P3–340: Decrease of BDNF serum concentration from MCI to early Alzheimer's disease
2006-07-01

Alzheimer's disease (AD) is characterized by cognitive decline and loss of neurons in specific brain regions. Patients with mild cognitive impairment (MCI) have an increased risk of developing AD. Recent findings have suggested an involvement of brain–derived neurotrophic factor (BDNF) in the pathogenesis of AD. BDNF is an endogenous protein involved in the maintenance of neuronal function, synaptic plasticity and structural integrity in the adult brain. In the present study, we assessed BDNF serum concentrations by ELISA in 12 patients with MCI with a MMSE score ≥ 26 (mean of 26,5 ± 0,8 SD), 30 patients with early stages of probable AD with a MMSE score < 26 + ≥ 21 (mean of 23,4 ± 1,3 SD) in comparison to 20 age–matched healthy controls. MCI patients showed significantly increased BDNF serum concentrations (24,1 ng/ml ± 5,4 SD) as compared to patients with early stages of AD (19,6 ng/ml ± 4,5 SD; p=0,011) and a trend of increase in comparison to healthy controls (21,1 ng/ml ± 4,7 SD; p=0,119). In addition, in MCI patients alone and in the combined sample of patients with MCI and AD, BDNF serum values correlated significantly with MMSE scores (r=0,855; p=0,001 / r=0,396; p=0,010). The correlation between BDNF serum concentrations and MMSE scores in MCI and AD patients indicates, that BDNF serum values may reflect BDNF levels in the brain. The trend of increased BDNF serum values in MCI could be due to a compensatory repair mechanism in early neurodegeneration. During early stages of AD, BDNF is decreasing. The significant decrease of BDNF serum values from MCI to early AD stages may constitute a lack of trophic support, thus contributing to progressive degeneration of specific regions in the AD–affected brain and favour the development of Alzheimer's disease.
CrossLink: visualization and exploration of sequence relationships between (micro) RNAs
2006-07-01

CrossLink is a versatile tool for the exploration of relationships between RNA sequences. After a parametrization phase, CrossLink delegates the determination of sequence relationships to established tools (BLAST, Vmatch and RNAhybrid) and then constructs a network. Each node in this network represents a sequence and each link represents a match or a set of matches. Match attributes are reflected by graphical attributes of the links and corresponding alignments are displayed on a mouse-click. The distributions of match attributes such as E-value, match length and proportion of identical nucleotides are displayed as histograms. Sequence sets can be highlighted and visibility of designated matches can be suppressed by real-time adjustable thresholds for attribute combinations. Powerful network layout operations (such as spring-embedding algorithms) and navigation capabilities complete the exploration features of this tool. CrossLink can be especially useful in a microRNA context since Vmatch and RNAhybrid are suitable tools for determining the antisense and hybridization relationships, which are decisive for the interaction between microRNAs and their targets. CrossLink is available both online and as a standalone version at http://www-ab.informatik.uni-tuebingen.de/software.
Analysis of a previous smallpox vaccination study: estimation of the time period required to acquire vaccine-induced immunity as assessed by revaccination.
2006-07-01

The time interval required to develop immunity after vaccination, in the event of a bioterrorist attack using variola virus, is yet to be clarified. In this article, a historical vaccination study conducted in Japan in 1929 was re-examined. Forty-four previously vaccinated and 44 unvaccinated children were involved. After successful first round primary (or re-) vaccination, all children underwent revaccination at variable intervals. Absence of a major reaction (vaccine 'take') after revaccination was taken as a sign of immunity conferred by first round primary (or re-) vaccination. Univariate analysis was employed to examine the relationship between vaccine 'take' and the exposure variables. Maximum likelihood estimates of the time period required to develop immunity were obtained using a simple logit model. The interval between vaccinations was significantly associated with vaccine 'take' in both the previously unvaccinated (p < 0.01) and vaccinated (p < 0.01) groups, and the median interval required for immunity after vaccination was estimated to be 6.4 [95% Confidence Interval (CI): 5.8, 7.1] and 4.3 days (95 % CI: 4.1, 4.7), respectively. Obtained estimates were consistent with previous observations, and the logistic fits reasonably explained the discrepancy among previous suggestions. The findings suggest that it is necessary to vaccinate exposed susceptible individuals within 3 days after exposure to ensure disease protection, and within at least 5 days (for those previously unvaccinated) to provide a certain level of protection; the probability shows a dramatic decline hereafter.
P2–082: A randomised, single–blind, placebo–controlled, multicentre study to investigate the pharmacodynamic effects of lithium on GSK–3 activity in patients with mild Alzheimer's disease
2006-07-01

Inhibition of glycogen synthase kinase 3 (GSK–3), leads to a reduction of hyperphosphorylated tau (p–tau) characteristic of AD, and has been identified as a potential target for AD drug development. Lithium is a weak inhibitor of GSK–3 and could be used as a probe to investigate degree of inhibition and time aspects of GSK–3 inhibition in patients with AD. However, to our knowledge, this has never been studied in humans. The primary objective of this 10–week placebo–controlled study was to investigate the pharmacodynamic effects of lithium treatment on GSK–3 activity in patients with mild AD by assessment of cerebrospinal fluid (CSF) levels of p–tau and GSK–3 activity in lymphocytes. The secondary objectives are to investigate the effects of lithium treatment on the CSF and plasma levels of β–amyloid 42 (Aβ42), total tau, and study the effects of cognitive function as measured by the Alzheimer's Disease Assessment Scale (ADAS–Cog), Mini–Mental State Examination (MMSE), and the Neuropsychiatric Inventory (NPI). The treatment and the placebo group comprised 33 and 38 patients, respectively. The patient was, after informed consent was signed, screened at the enrollment visit. The screening procedure included vital signs, a standard physical examination, clinical chemistry, ECG, hematology, urinalysis and a measure of cognitive function (MMSE). Plasma, ADAS–Cog and NPI was collected at baseline and at the end of treatment. Blood was sampled 6 times during the 10 week study period. Preliminary results showed a 30% clinically significant improvement of 4–points or more on the ADAS–Cog scale in the Lithium group as compared to a 10% improvement in the placebo group. The analysis of the p–tau, GSK–3, NPI, and MMSE data is ongoing at present but will be reported at the meeting.
P3–280: Higher peripheral regulatory T cell activity in parkinson but not Alzheimer's disease
2006-07-01

Neuroinflammation is an established fact in neurodegenerative disorders like Alzheimer's (AD) and Parkinson disease (PD). Whether this inflammation is cause or consequence of the disease is still unknown. However, due to promising immunization studies in animal models for both diseases, the idea has evolved that a beneficial autoimmune response can prevent disease development. Even though this idea and the relevant effector mechanisms remain to be proven, we decided to analyze peripheral regulatory T cells (Treg) from AD and PD patients. The working hypothesis behind our study is, that higher activity or numbers of Treg could suppress a beneficial immune response, resulting in, or accelerating, either AD or PD. Four different groups have been analyzed: AD and PD patients as well as healthy young and aged–matched non–demented individuals (n > 30 for all groups). Our findings indicate that all elderly groups have a higher Treg (CD4+Foxp3+) frequency compared to the young group, without any difference between the elderly groups. In addition, we observed increasing Treg activity for all elderly groups compared to the young group. However, no difference between the aged healthy individuals and AD patients could be observed. In contrast, Treg activity in PD patients was significantly higher compared to the aged healthy donors. The increase of suppressive activity was thereby independent of the Foxp3 expression level. Our observations, of quantitative and qualitative differences already in the total pool of peripheral Treg between young and elderly groups, identify Treg as an immune–cell type undergoing immunological senescence. Taking into account that changes in Treg function increase with a neurodegenerative phenotype present in PD patients, our data support the hypothesis of an existing beneficial autoimmune effector mechanism in these patients, which is suppressed by Treg. Furthermore, we cannot exclude that by analyzing a more specialized subset of Treg in AD patients a similar result would be obtained for this group. Consequently, it will be of special interest to analyze Treg specific for CNS antigens relevant to AD and PD, in particular amyloid–beta and alpha–synuclein.
METHODS AND APPLICATIONS IN MICROPALAEONTOLOGY: Edited By J. Tyszka, M. Oliwkiewicz-Miklasinska, P. Gedl and M. A. Kaminski, 2005, Studia Geologica Polonica, v. 124, Polska Akademia Nauk, Poland, 410 pp; ISBN: 83-918081-4-9; List price: 30.00 or $36.00 (both prices include surface postage); http://www.ing.pan.pl/stud4www/Front124.html.
2006-07-01

Book Review| July 01, 2006 METHODS AND APPLICATIONS IN MICROPALAEONTOLOGY: Edited By J. Tyszka, M. Oliwkiewicz-Miklasińska, P. Gedl and M. A. Kaminski, 2005, Studia Geologica Polonica, v. 124, Polska Akademia Nauk, Poland, 410 pp; ISBN: 83-918081-4-9; List price: €30.00 or 36.00 (both prices include surface postage); http://www.ing.pan.pl/stud4www/Front124.html.. Journal of Foraminiferal Research 2006;; 36 (3): 276. doi: https://doi.org/10.2113/gsjfr.36.3.276 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyJournal of Foraminiferal Research Search Advanced Search Micropaleontology continues to evolve into a broad and methodologically diverse field. Since the day has only 24 hours, reviews and occasional state-of-the-art syntheses are increasingly important to catch up with the latest developments. Like many practitioners of the science watching the scene, we could not to fail to notice the appearance of a new book entitled “Methods and Applications in Micropaleontology”. The title of the book immediately awakened our curiosity. A comprehensive dedicated tome with such content is long overdue, since existing works either treat methods only in passing or are desperately outdated. Could this be the much-needed, up-to-date synthesis?... You do not have access to this content, please speak to your institutional administrator if you feel you should have access.
P4–409: Detection of serum antibodies against CNS proteins in health and neurodegenerative disease associated with dementia
2006-07-01

Self–reactive antibodies may play a considerable role in the removal of potentially toxic CNS proteins from the peripheral blood that would otherwise accumulate in the aged CNS (peripheral sink hypothesis). The occurrence of natural CNS–reactive antibodies is not well known. It has been shown that vaccination with amyloid–beta (1–42) can induce a considerable antibody response in patients suffering from Alzheimer's disease (AD), which has been linked to clinical improvement. In addition, antibodies against amyloid–beta (1–42) can be detected in the peripheral blood of healthy individuals. Therefore, with regard to the induction of antibodies, the natural antibody repertoire against CNS proteins appears to be of particular interest. We explored the occurrence of natural antibodies against a mixture of CNS proteins, and in particular amyloid–beta (1–42) and alpha–synuclein that play a pathogenic role in neurodegenerative diseases associated with dementia, such as AD and dementia with Lewy bodies (DLB). Serum antibodies from young and elderly individuals, as well as, patients with AD and DLB were determined by Western Blot and ELISA. Surprisingly, we detected antibodies against amyloid–beta (1–42), alpha–synuclein and the mixture of CNS proteins in healthy individuals and patients with neurodegenerative disease. The presence of CNS–specific antibodies in the peripheral blood points to their potential relevance in maintaining an equilibrium of CNS proteins or their degradation products with the peripheral circulation.
Corporate and Personal Income Tax Declarations
2006-07-01

Decisions by firms and individuals on the extent of their tax payments have generally been treated as separate choices. Empirically, a positive relationship between corporate and personal income tax evasion can be observed. The theoretical analysis in this paper shows that a manager's decision on the firm's behaviour will be independent of his personal preferences if the gain from reducing corporate tax payments is certain, as in the case of tax avoidance. If, however, the firm evades taxes so that the manager's income depends on whether the firm's activities are detected or not, corporate and personal income tax evasion choices cannot be separated.
M[B(CN)4]2: Two New Tetracyanoborate Compounds with Divalent Cations (M: Zn, Cu).
2006-07-03

Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
A Resourceful Access to α‐Functionalized Arylhydrazones.
2006-07-03

Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Comparative proteome analyses of maize (Zea mays L.) primary roots prior to lateral root initiation reveal differential protein expression in the lateral root initiation mutant rum1
2006-07-04

Abstract The embryonically preformed primary root is the first root type of maize that emerges after germination. In this study the abundant soluble proteins of 2.5‐day‐old primary roots of wild‐type and lateral root mutant rum1 seedlings were compared before the initiation of lateral roots. In CBB‐stained 2‐D gels, among 350 detected proteins 14 were identified as differentially accumulated (&gt;twofold change; t ‐test: 95% significance) in wild‐type versus rum1 primary roots. These proteins which were identified via ESI MS/MS are encoded by 12 different genes. Functionally, these proteins are involved in lignin biosynthesis, defense, and the citrate cycle. Nine of these genes were further analyzed at the RNA expression level. This study represents the first comparative proteomic analysis of maize primary roots prior to lateral root initiation and will contribute to a better understanding of the molecular basis of root development in cereals.
The PDZ-GEF Dizzy regulates cell shape of migrating macrophages via Rap1 and integrins in theDrosophilaembryo
2006-07-05

In Drosophila embryos, macrophages originate from the cephalic mesoderm and perform a complex migration throughout the entire embryo. The molecular mechanisms regulating this cell migration remain largely unknown. We identified the Drosophila PDZ G-nucleotide exchange factor (PDZ-GEF)Dizzy as a component essential for normal macrophage migration. In mutants lacking Dizzy, macrophages have smaller cellular protrusions, and their migration is slowed down significantly. This phenotype appears to be cell-autonomous, as it is also observed in embryos with a dsRNA-induced reduction of dizzy function in macrophages. In a complementary fashion, macrophages overexpressing Dizzy are vastly extended and form very long protrusions. These cell shape changes depend on the function of the small GTPase Rap1: in rap1 mutants, Dizzy is unable to induce the large protrusions. Furthermore, forced expression of a dominant-active form of Rap1,but not of the wild-type form, induces similar cell shape changes as Dizzy does overexpression. These findings suggest that Dizzy acts through Rap1. We propose that integrin-dependent adhesion is a Rap1-mediated target of Dizzy activity: in integrin mutants, neither Dizzy nor Rap1 can induce cell shape changes in macrophages. These data provide the first link between a PDZ-GEF,the corresponding small GTPase and integrin-dependent cell adhesion during cell migration in embryonic development.
Redox-Active Silica Nanoparticles. Part 1. Electrochemistry and Catalytic Activity of Spherical, Nonporous Silica Particles with Nanometric Diameters and Covalently Bound Redox-active Modifications,
2006-07-06

Nonporous spherical silica nanoparticles resulting from a controlled Stöber process are covalently surface modified with redox-active molecules. Ferrocene, a ruthenium(II) complex with an N2P2Cl2 ligand set, and a sterically hindered biphenylamine are used as modifiers. The resulting materials are characterized by physical, spectroscopic, electrochemical, and chemical methods. The cyclic voltammetric behavior is studied in detail and reveals effects of charge transport by electron hopping along the surface of particles adsorbed on a Pt electrode. The ruthenium(II) complex remains catalytically active with respect to hydrogenation upon immobilization on the particles. Thus, the respective material provides a heterogenized homogeneous hydrogenation catalyst on a solid support.
Crucial Mitochondrial Impairment upon CDC48 Mutation in Apoptotic Yeast
2006-07-06

Mutation in CDC48 (cdc48(S565G)), a gene essential in the endo-plasmic reticulum (ER)-associated protein degradation (ERAD) pathway, led to the discovery of apoptosis as a mechanism of cell death in the unicellular organism Saccharomyces cerevisiae. Elucidating Cdc48p-mediated apoptosis in yeast is of particular interest, because Cdc48p is the highly conserved yeast orthologue of human valosin-containing protein (VCP), a pathological effector for polyglutamine disorders and myopathies. Here we show distinct proteomic alterations in mitochondria in the cdc48(S565G) yeast strain. These observed molecular alterations can be related to functional impairment of these organelles as suggested by respiratory deficiency of cdc48(S565G) cells. Mitochondrial dysfunction in the cdc48(S565G) strain is accompanied by structural damage of mitochondria indicated by the accumulation of cytochrome c in the cytosol and mitochondrial enlargement. We demonstrate accumulation of reactive oxygen species produced predominantly by the cytochrome bc1 complex of the mitochondrial respiratory chain as suggested by the use of inhibitors of this complex. Concomitantly, emergence of caspase-like enzymatic activity occurs suggesting a role for caspases in the cell death process. These data strongly point for the first time to a mitochondrial involvement in Cdc48p/VCP-dependent apoptosis.
Processing of Information in the Human Visual System
2006-07-06

This chapter contains sections titled: Preface Design and Structure of the Eye Optical Aberrations and Consequences for Visual Performance Chromatic Aberration Neural Adaptation to Monochromatic Aberrations Optimizing Retinal Processing with Limited Cell Numbers, Space and Energy Adaptation to Different Light Levels Rod and Cone Responses Spiking and Coding Temporal and Spatial Performance ON/OFF Structure, Division of the Whole Illuminance Amplitude in Two Segments Consequences of the Rod and Cone Diversity on Retinal Wiring Motion Sensitivity in the Retina Visual Information Processing in Higher Centers Morphology Functional Aspects – Receptive Field Structures and Cortical Modules Effects of Attention Color Vision, Color Constancy, and Color Contrast Depth Perception Adaptation in the Visual System to Color, Spatial, and Temporal Contrast Conclusions