julilili42/papers huggingface dataset:
Synthesis and Structure of a Zwitterionic Imidazolium 1,3-Dioxanide
2003-08-01

{Bis(methylthio)methylene}-2,2-dimethyl-4,6-dioxo-1,3- dioxane (7) reacts with cis-1,2-diamino-1,2-dicyanoethene to give 2,2-dimethyl-4,6-dioxo-5-{2-(4,5-dicyano)} imidazolio-1,3-dioxan-5-yl-imidazolium ylide (8) as a stable crystalline solid in good yield. The crystal structure of 8 × C 3 H 6 OS is discussed.
Development and application of new C30-modified TLC plates
2003-08-01

This paper reports the efficiency of the C 30 phase for HPLC and TLC separation of a mixture of tocopherol homologs and α -tocopherol acetate, in comparison with C 18 and unmodified silica gel. The C 30 TLC plates were prepared by the modification of silica gel plates with triacontyltrichlorosilane, using different ratios of the modifying agent. The novel TLC plates were characterized by use of 13 C and 29 Si solid-state cross-polarization magic-angle spinning (CP/MAS) NMR spectroscopy, which furnished detailed information about the structure of the resulting surface species, the chain order, and the mobility of the alkyl chain moiety. Chromatographic results showed these new TLC phases can be used for rapid separation of a tocopherol mixture. These new plates could therefore be of great interest for rapid, high-throughput screening.
Novel Zwitterionic Sulfides, Selenides and Tellurides
2003-08-01

Abstract The zwitterionic compounds Im‐E‐Mel [ 9 , E = S ( a ), Se ( b ), Te ( c ), Im = 2‐{1, 3‐diisopropyl‐4, 5‐dimethylimidazolium}, Mel = 5‐{2, 2‐dimethyl‐4, 6‐dioxo‐1, 3‐dioxan‐5‐ylide}] are obtained from the corresponding 2‐chalcogeno‐1, 3‐diisopropyl‐4, 5‐dimethylimidazolines 8 and 5‐bromo‐2, 2‐dimethyl‐4, 6‐dioxo‐1, 3‐dioxan ( 7 ) in the presence of triethylamine in excellent yields. The crystal structures of the thermally stable compounds reveal most effective charge separations from which the compounds 9 resemble closely to diaryl chalkogenides. 9b and 9c are the first selenocarbonyl and tellurocarbonyl ylides reported, to our knowledge.
A Six-Quark Dressed-Bag Description of np→dγ Radiative Capture
2003-08-01

The radiative capture process np→dγ is considered within the framework of a recently developed six-quark dressed-bag model for the nucleon-nucleon interaction. The calculations presented here include both the nucleon current and the meson-exchange current contributions. The latter uses short-range hadronic form factors for the pion exchange currents consistent with the soft cut-off parameter Λ πNN from the NN-potential. Contributions of the pion exchange current and Δ-isobar current to the total cross-section still cannot explain the discrepancy between the theoretical and experimental cross-sections. Possibilities for new types of meson exchange currents associated with chiral fields inside multi-quark dressed-bag states in nuclei are discussed.
KUGO–OJIMA CONFINEMENT CRITERION, ZWANZIGER–GRIBOV HORIZON CONDITION, AND INFRARED CRITICAL EXPONENTS IN LANDAU GAUGE QCD
2003-08-01

The Kugo-Ojima confinement criterion and its relation to the infrared\\nbehaviour of the gluon and ghost propagators in Landau gauge QCD are reviewed.\\nThe realization of this confinement criterion (which in Landau gauge relates to\\nZwanziger's horizon condition) results from quite general properties of the\\nghost Dyson-Schwinger equation. The numerical solutions for the gluon and ghost\\npropagators obtained from a truncated set of Dyson-Schwinger equations provide\\nan explicit example for the anticipated infrared behaviour. These results are\\nin good agreement, also quantitatively, with corresponding lattice data\\nobtained recently. The resulting running coupling approaches a fixed point in\\nthe infrared, . Solutions for the coupled system of\\nDyson-Schwinger equations for the quark, gluon and ghost propagators are\\npresented. Dynamical generation of quark masses and thus spontaneous breaking\\nof chiral symmetry is found. In the quenched approximation the quark propagator\\nfunctions agree well with those of corresponding lattice calculations. For a\\nsmall number of light flavours the quark, gluon and ghost propagators deviate\\nonly slightly from the quenched ones. While the positivity violation of the\\ngluon spectral function is apparent in the gluon propagator, there are no clear\\nindications of positivity violations in the Landau gauge quark propagator.\\n
Randomized Response and the Binary Probit Model
2003-08-01

The paper analyzes eects of randomized response with respect to some binary dependent variable on the estimation of the probit model. This approach is used in interviews when asking sensitive questions. Alternatively randomization can be considered as a means of statistical disclosure control which has been termed post randomization method (PRAM). The paper shows that all properties concerning parameter estimation are maintained although there is a loss in (asymptotic) eciency.
Reconstructive urology
2003-08-01

Although some controversies still exist, data on age adjusted deaths from CaP obtained from the Surveillance, Epidemiology, and End Results database from 1990 to 1998 in the USA revealed that Black American men have 2.3 times greater mortality from CaP than white American men.Previous works demonstrated that Black men are more frequently diagnosed with higher tumor volume, more advanced tumor stage, higher Gleason grade and higher prostate specific antigen (PSA) levels than white men are.The reasons for such findings are still not well understood.This is the first study measuring and comparing androgen receptor (AR) protein expression in malignant and benign prostate tissue from black and white men who underwent radical prostatectomy for clinically localized CaP.The authors found that AR protein expression was 22% higher in the benign prostate and 81% higher in the CaP of black compared with white American men.Based on these findings, the authors speculated that CaP might occur at a younger age and progress more rapidly in black than in white men due to racial differences in androgenic stimulation of the prostate.
Electron probe microanalysis of Mg–B compounds: stoichiometry and heterogeneity of superconductors
2003-08-01

The cover picture of the present issue of physica status solidi (a) is a false-colour representation of the back-scattered electron image from the surface of MgB12 (sample 2 of Ref. [1]). It shows the heterogeneity of the magnesium boride grains in the synthesized powders. The red colour approximately corresponds to the MgB12 phase and orange to the MgB7 phase, respectively; the yellow dots are holes in the sample.
Glacial North Atlantic: Sea‐surface conditions reconstructed by GLAMAP 2000
2003-08-02

The response of the tropical ocean to global climate change and the extent of sea ice in the glacial nordic seas belong to the great controversies in paleoclimatology. Our new reconstruction of peak glacial sea surface temperatures (SSTs) in the Atlantic is based on census counts of planktic foraminifera, using the Maximum Similarity Technique Version 28 (SIMMAX‐28) modern analog technique with 947 modern analog samples and 119 well‐dated sediment cores. Our study compares two slightly different scenarios of the Last Glacial Maximum (LGM), the Environmental Processes of the Ice Age: Land, Oceans, Glaciers (EPILOG), and Glacial Atlantic Ocean Mapping (GLAMAP 2000) time slices. The comparison shows that the maximum LGM cooling in the Southern Hemisphere slightly preceeded that in the north. In both time slices sea ice was restricted to the north western margin of the nordic seas during glacial northern summer, while the central and eastern parts were ice‐free. During northern glacial winter, sea ice advanced to the south of Iceland and Faeroe. In the central northern North Atlantic an anticyclonic gyre formed between 45° and 60°N, with a cool water mass centered west of Ireland, where glacial cooling reached a maximum of &gt;12°C. In the subtropical ocean gyres the new reconstruction supports the glacial‐to‐interglacial stability of SST as shown by CLIMAP Project Members ( CLIMAP ) [1981] . The zonal belt of minimum SST seasonality between 2° and 6°N suggests that the LGM caloric equator occupied the same latitude as today. In contrast to the CLIMAP reconstruction, the glacial cooling of the tropical east Atlantic upwelling belt reached up to 6°–8°C during Northern Hemisphere summer. Differences between these SIMMAX‐based and published U 37 k ‐ and Mg/Ca‐based equatorial SST records are ascribed to strong SST seasonalities and SST signals that were produced by different planktic species groups during different seasons.
A dressed-bag model study of the short-rangeN interaction in pion photoproduction processes off the deuteron
2003-08-04

The impact of the short-range interaction on the pion\\nphotoproduction processes off the deuteron in the -resonance region is\\nstudied in the framework of recently proposed dressed-bag model. A common\\ndressing procedure for bare three- and six-quark states is used to describe\\nboth the pion decay widths of baryon resonances and the effective (or\\n ) interaction at short ranges related to the inner dressed-bag\\nstates. It is shown that the effect of short-range interaction for\\nthe forward-angle photoproduction off the deuteron cannot be\\nneglected. The prospects for further development of the model to describe the\\nshort-range (or ) correlations in the lightest nuclei are\\ndiscussed.\\n
Representation of the Perceived 3-D Object Shape in the Human Lateral Occipital Complex
2003-08-05

We used human functional magnetic resonance imaging (fMRI) to test whether the human lateral occipital complex (LOC), an area known to be involved in the analysis of visual shape, represents the perceived 3-D shape of objects or simply their 2-D contours. We employed an fMRI adaptation paradigm, in which repeated presentation of a stimulus results in decreased responses compared to responses to different stimuli. We found adaptation in the LOC for images of objects with the same perceived 3-D shape structure but different 2-D contours that resulted from small rotations of the objects in the frontal plane or in depth. However, no adaptation was observed in the LOC for images of objects that had the same 2-D contours but differed in their perceived 3-D shape; namely, 2-D silhouettes versus 3-D shaded images of objects, or convex versus concave objects. Differences in the fMRI adaptation responses across subregions in the LOC suggest that different neural populations in the LOC may mediate different mechanisms for the processing of object features.
Site‐directed mutagenesis of the ATM promoter: Consequences for response to proliferation and ionizing radiation
2003-08-06

Abstract Although ATM, the protein defective in ataxia‐telangiectasia (A‐T), is activated primarily by radiation, there is also evidence that expression of the protein can be regulated by both radiation and growth factors. Computer analysis of the ATM promoter proximal 700‐bp sequence reveals a number of potentially important cis ‐regulatory sequences. Using nucleotide substitutions to delete putative functional elements in the promoter of ATM , we examined the importance of some of these sites for both the basal and the radiation‐induced activity of the promoter. In lymphoblastoid cells, most of the mutations in transcription factor consensus sequences [Sp1(1), Sp1(2), Cre, Ets, Xre, γIre(2), a modified AP1 site (Fse), and GCF] reduced basal activity to various extents, whereas others [γIre(1), NF1, Myb] left basal activity unaffected. In human skin fibroblasts, results were generally the same, but the basal activity varied up to 8‐fold in these and other cell lines. Radiation activated the promoter approximately 2.5‐fold in serum‐starved lymphoblastoid cells, reaching a maximum by 3 hr, and all mutated elements equally blocked this activation. Reduction in Sp1 and AP1 DNA binding activity by serum starvation was rapidly reversed by exposure of cells to radiation. This reduction was not evident in A‐T cells, and the response to radiation was less marked. Data provided for interaction between ATM and Sp1 by protein binding and co‐immunoprecipitation could explain the altered regulation of Sp1 in A‐T cells. The data described here provide additional evidence that basal and radiation‐induced regulation of the ATM promoter is under multifactorial control. © 2003 Wiley‐Liss, Inc.
The Self in Neuroscience and Psychiatry
2003-08-07

In recent years the clinical and cognitive sciences and neuroscience have contributed important insights to understanding the self. The neuroscientific study of the self and self-consciousness is in its infancy in terms of established models, available data and even vocabulary. However, there are neuropsychiatric conditions, such as schizophrenia, in which the self becomes disordered and this aspect can be studied against healthy controls through experiment, building cognitive models of how the mind works, and imaging brain states. In this 2003 book, the first to address the scientific contribution to an understanding of the self, an eminent, international team focuses on current models of self-consciousness from the neurosciences and psychiatry. These are set against introductory essays describing the philosophical, historical and psychological approaches, making this a uniquely inclusive overview. It will appeal to a wide audience of scientists, clinicians and scholars concerned with the phenomenology and psychopathology of the self
Synthesis, NMR Spectroscopic Characterization and Polysiloxane‐Based Immobilization of the Three Regioisomeric Monooctenylpermethyl‐β‐cyclodextrins and Their Application in Enantioselective GC
2003-08-07

Abstract 2 I−VI ,3 I−VII ,6 I−VII ‐Eicosa‐ O ‐methyl‐2 I ‐ O ‐(oct‐7‐enyl)cyclomaltoheptaose, 2 I−VII ,3 I−VI ,6 I−VII ‐eicosa‐ O ‐methyl‐3 I ‐ O ‐(oct‐7‐enyl)cyclomaltoheptaose, and 2 I−VII ,3 I−VII ,6 I−VI ‐eicosa‐ O ‐methyl‐6 I ‐ O ‐(oct‐7‐enyl)cyclomaltoheptaose were synthesized by selective introduction of an oct‐7‐enyl group at one of the O ‐2, O ‐3, or O ‐6 positions of selectively methylated cyclomaltoheptaose (β‐cyclodextrin, CD) and, depending on the synthetic route, by a subsequent permethylation step. Each of the regioisomeric mono‐oct‐7‐enylated permethylated β‐cyclodextrin derivatives was anchored by hydrosilylation to a hydridomethyldimethylsiloxane copolymer to yield unambiguously O ‐2‐, O ‐3‐, and O ‐6‐bonded chiral stationary phases (CSP) of Chirasil‐Dex, which were evaluated in enantioselective gas chromatography (GC). O ‐6‐Chirasil‐Dex displayed slightly inferior enantioselectivity relative to either O ‐3‐ or O ‐2‐Chirasil‐Dex. The statistical synthesis of the CSP by mono‐oct‐7‐enylation of β‐CD under varying reactions conditions (base, solvent), without the use of hydroxy group protection chemistry, furnished a mixture of O ‐6‐ and O ‐2‐Chirasil‐Dex in dimethylformamide and predominantly the O ‐2‐regioisomer in dimethyl sulfoxide. Chirasil‐Dex, previously formulated exclusively as the O ‐6 regioisomer, should be revised as an O ‐2‐ and O ‐6‐Chirasil‐Dex mixture. (© Wiley‐VCH Verlag GmbH &amp; Co. KGaA, 69451 Weinheim, Germany, 2003)
Self-consciousness: an integrative approach from philosophy, psychopathology and the neurosciences
2003-08-07

In this chapter, we want to try and integrate the divergent lines introduced in the other parts of this book. We propose a model of self-consciousness derived from phenomenology, philosophy, the cognitive and neurosciences. We will then give an overview of research data on self-processing from various fields and link it to our model. Some aspects of the disturbances of the self in pathological states such as brain lesions and schizophrenia will be discussed. Finally, the clinically important concept of insight into a disease and its neurocognitive origin will be introduced. We argue that self-consciousness is a valid construct and, as shown in this chapter, it is possible that it can be studied with the instruments of cognitive neuroscience.
The myth of dorsal ribs in gnathostome vertebrates
2003-08-07

Traditionally, two types of rib are distinguished in gnathostomes: dorsal (upper) and ventral (lower, pleural) ribs. They are defined according to their position in the connective tissue system of the body: dorsal ribs develop at the intersection of the serially arranged myosepta with the horizontal septum that separates epaxial from hypaxial musculature, whereas ventral ribs develop at the intersection of myosepta with the peritoneum and usually encircle the body cavity. Distribution of rib types among gnathostomes has traditionally been reported as follows: elasmobranchs have dorsal ribs; all Actinopterygii have only ventral ribs with the exception of polypterids, and two subgroups of teleosts, which supposedly also have dorsal ribs; within Sarcopterygii tetrapods have dorsal ribs, whereas dipnoans have ventral ribs. Here, we report the development of ribs in polypterids, a taxon playing a crucial role in discussions on rib homology. We demonstrate that putative dorsal ribs of polypterids have a unique ontogeny and represent an autapomorphy of this taxon. We discuss previous hypotheses of rib homology and offer a more plausible (i.e. more parsimonious) alternative to the conventional interpretation. We conclude that dorsal ribs do not exist and that ribs of gnathostomes are ventral ribs.
Introduction: the self and neuroscience
2003-08-07

Who are we and what makes us who we are? Like our world, our self is a construction of our minds. But we do not live in isolation. The self is also a construction of our relations with other selves. And most intriguingly, the self is a construction of its relation with itself. One question is, how does the mind construct this world and ourselves in it? Constantly we think, feel, decide, perceive. Understanding how these things happen is central to our grasp of what kind of being we are. The way our mental life is constituted is also important to our understanding of who we are individually, because the variation of our mental lives constitutes our feeling of differentiation between our fellow humans. Mental states, unlike most other things of our everyday experience, have no spatial characteristics and they do not seem to belong to a world constituted by physical things. How to place our mental experience in the physical universe is therefore perplexing. Mental phenomena also interest us because we infer from ourselves that others have similar mental experiences. Social interactions require us to understand each other's thoughts and feelings. And language would not exist as a medium of expressing our inner world without our elaborate cognitive abilities. We seem to understand the content of our mind readily from our own experience. The problem arises when we try to know objectively, independently from ourselves, what we experience.
Testing the climatic estimates from different palaeobotanical methods: an example from the Middle Miocene Shanwang flora of China
2003-08-08

The Miocene Shanwang biota from eastern China contains exceptionally well-preserved plant fossils with abundant leaf fossils and palynomorphs co-occurring at several levels in the sedimentary succession. This has provided an ideal opportunity to undertake detailed comparative quantitative palaeoclimate reconstruction, based on both mega- and microfloral assemblages, using various approaches, namely the coexistence approach (CoA), leaf margin analysis (LMA) and Climate Leaf Analysis Multivariate Programme (CLAMP). By applying these approaches to the same dataset and using multiple fossil assemblages from different levels we are able to compare results from the different methods of climate prediction. CLAMP and LMA give consistently lower temperature (mean annual temperature, MAT) predictions than the CoA. Taking errors into account all methods indicate no overall climate change through the sequence studied. Results from CoA show overall agreement in the palaeoclimate parameters obtained using both pollen and leaf datasets indicating a high degree of internal consistency with this method.
Infrared behavior of gluons and ghosts in ghost-antighost symmetric gauges
2003-08-08

To investigate the possibility of a ghost-antighost condensate, the coupled Dyson-Schwinger equations for the gluon and ghost propagators in Yang-Mills theories are derived in general covariant gauges, including ghost-antighost symmetric gauges. The infrared behavior of these two-point functions is studied in a barevertex truncation scheme which has proven to be successful in the Landau gauge. In all linear covariant gauges the same infrared behavior as in the Landau gauge is found: The gluon propagator is infrared-suppressed whereas the ghost propagator is infrared-enhanced. This infrared singular behavior provides an indication against a ghost-antighost condensate. In the ghost-antighost symmetric gauges we find that the infrared behavior of the gluon and ghost propagators cannot be determined when replacing all dressed vertices by bare ones. The question of a BRS invariant dimension-2 condensate remains to be further studied.
Differential peptide binding motif for three juvenile arthritis associated HLA-DQ molecules.
2003-08-08

These results imply a role for differential peptide presentation in the pathogenesis of oligoarthritic JIA. The search for peptides initiating the disease process might be facilitated which could then lead to therapeutical interventions.
Long term variability of Cygnus X–1
2003-08-11

We present the long term evolution of the timing properties of the black hole candidate Cygnus X-1 in the 0.002-128 Hz frequency range as monitored from 1998 to 2001 with the RXTE. The hard state power spectral density (PSD) is well modeled as the sum of four Lorentzians, which describe distinct broad noise components. Before 1998 July, Cyg X-1 was in a "quiet" hard state characterized primarily by the first three of these broad Lorentzians. Around 1998 May, this behavior changed: the total fractional rms amplitude decreased, the peak frequencies of the Lorentzians increased, the average time lag slightly increased, and the X-ray spectrum softened. The change in the timing parameters is mainly due to a strong decrease in the amplitude of the third Lorentzian. Since then, an unusually large number of X-ray flares have been observed. During these "failed state transitions", the X-ray power spectrum changes to that of the intermediate state. Modeling this PSD with the four Lorentzians, we find that the first Lorentzian component is suppressed relative to the second and third Lorentzian. Also the frequency-dependent time lags increase significantly. We confirm the interpretation as failed state transitions with observations from the 2001 Jan. and 2001 Oct. soft states. Such behavior suggests that some or all of the Lorentzian components are associated with the accretion disk corona. We discuss the physical interpretation of our results.