bluuebunny/crossref_metadata_2025_split huggingface dataset:
First Preparation of Nanocrystalline Zinc Silicate by Chemical Vapor Synthesis Using an Organometallic Single‐Source Precursor
Authors: Roy A. , Polarz S. , Rabe S. , Rellinghaus B. , Zähres H. , Kruis F. E. , Driess Matthias 
Published: March 2004

AbstractA method is presented to prepare nanocrystalline α‐Zn2SiO4 with the smallest crystal size reported so far for this system. Our approach combines the advantages of organometallic single‐source precursor routes with aerosol processing techniques. The chemical design of the precursor enables the preferential formation of pure zinc silicates. Since gas‐phase synthesis reduces intermolecular processes, and keeps the particles small, zinc silicate was synthesized from the volatile organometallic precursor [{MeZnOSiMe3}4], possessing a Zn‐methyl‐ and O‐silyl‐substituted Zn4O4‐heterocubane framework (cubane), under oxidizing conditions, using the chemical vapor synthesis (CVS) method. The products obtained under different process conditions and their structural evolution after sintering were investigated by using various analytical techniques (powder X‐ray diffraction, transmission electron microscopy, EDX analysis, solid‐state NMR, IR, Raman, and UV/Vis spectroscopy). The deposited aerosol obtained first (processing temperature 750 °C) was amorphous, and contained agglomerates with primary particles of 12 nm in size. These primary particles can be described by a [Zn‐O‐Si] phase without long‐range order. The deposit obtained at 900 °C contained particles with embedded nanocrystallites (3–5 nm) of β‐Zn2SiO4, Zn1.7SiO4, and ZnO in an amorphous matrix. On further ageing, the as‐deposited particles obtained at 900 °C form α‐Zn2SiO4 imbedded in amorphous SiO2. The crystallite sizes and primary particle sizes in the formed α‐Zn2SiO4 were found to be below ∼50 nm and mainly spherical in morphology. A gas‐phase mechanism for the particle formation is proposed. In addition, the solid‐state reactions of the same precursor were studied in detail to investigate the fundamental differences between a gas‐phase and a solid‐state synthesis route.
A Rationale for the Large Breathing of the Porous Aluminum Terephthalate (MIL‐53) Upon Hydration
Authors: Loiseau Thierry , Serre Christian , Huguenard Clarisse , Fink Gerhard , Taulelle Francis , Henry Marc , Bataille Thierry , Férey Gérard 
Published: March 2004

AbstractAluminum 1,4‐benzenedicarboxylate Al(OH)[O2CC6H4CO2]⋅ [HO2CC6H4CO2H]0.70 or MIL‐53 as (Al) has been hydrothermally synthesized by heating a mixture of aluminum nitrate, 1,4‐benzenedicarboxylic acid, and water, for three days at 220 °C. Its 3 D framework is built up of infinite trans chains of corner‐sharing AlO4(OH)2 octahedra. The chains are interconnected by the 1,4‐benzenedicarboxylate groups, creating 1 D rhombic‐shaped tunnels. Disordered 1,4‐benzenedicarboxylic acid molecules are trapped inside these tunnels. Their evacuation upon heating, between 275 and 420 °C, leads to a nanoporous open‐framework (MIL‐53 ht (Al) or Al(OH)[O2CC6H4CO2]) with empty pores of diameter 8.5 Å. This solid exhibits a Langmuir surface area of 1590(1) m2 g−1 together with a remarkable thermal stability, since it starts to decompose only at 500 °C. At room temperature, the solid reversibly absorbs water in its tunnels, causing a very large breathing effect and shrinkage of the pores. Analysis of the hydration process by solid‐state NMR (1H, 13C, 27Al) has clearly indicated that the trapped water molecules interact with the carboxylate groups through hydrogen bonds, but do not affect the hydroxyl species bridging the aluminum atoms. The hydrogen bonds between water and the oxygen atoms of the framework are responsible for the contraction of the rhombic channels. The structures of the three forms have been determined by means of powder X‐ray diffraction analysis. Crystal data for MIL‐53 as (Al) are as follows: orthorhombic system, Pnma (no. 62), a = 17.129(2), b = 6.628(1), c = 12.182(1) Å; for MIL‐53 ht (Al), orthorhombic system, Imma (no. 74), a = 6.608(1), b = 16.675(3), c = 12.813(2) Å; for MIL‐53 lt (Al), monoclinic system, Cc (no. 9), a = 19.513(2), b = 7.612(1), c = 6.576(1) Å, β = 104.24(1)°.
Shape‐Persistent Macrocycles: From Molecules to Materials
Authors: Höger Sigurd 
Published: March 2004

AbstractShape‐persistent macrocycles with an interior in the nanometer regime allow the attachment of (functional) side groups at defined positions at the ring. These side groups can have either a fixed orientation relative to the molecular backbone or they can adapt their orientation according to an external stimulus. The properties and applications of the compounds depend strongly on the orientation of these side groups. Macrocycles with intraannular or adaptable long alkyl groups display a new design principle for discotic liquid crystals. Macrocycles with extraannular (oligo)alkyl groups can be used for surface patterning in the nanometer regime and rings with extraannular oligostyryl groups are able to aggregate to supramolecular hollow polymer brushes.
Self‐Assembly of Tris(2‐ureidobenzyl)amines: A New Type of Capped, Capsule‐Like Dimeric Aggregates Derived from a Highly Flexible Skeleton
Authors: Alajarín Mateo , Pastor Aurelia , Orenes Raúl‐Ángel , Steed Jonathan W. , Arakawa Ryuichi 
Published: March 2004

AbstractA set of tris(2‐ureidobenzyl)amines 3 was prepared and their dimerization processes thoroughly investigated. In spite of their inherent flexibility, tris(ureas) 3 form dimeric aggregates both in the solid state and in solution. Evidence for the existence of these dimeric species was provided by a combination of techniques (X‐ray analysis, NMR and IR spectroscopy, and ESI‐MS). The association constants and thermodynamic parameters for the dimerization processes of selected tris(ureas) were determined and show that they are enthalpically driven. Heterodimerization experiments in solution reveal a high degree of self‐recognition or narcissistic self‐sorting. On the other hand, desymmetrized tris(ureas) derived from 3 self‐assemble with modest regioselectivities depending on the terminal substituent of every urea functionality.
Fredholm theory and transversality for noncompact pseudoholomorphic mapsin symplectizations
Authors: Dragnev Dragomir L. 
Published: March 2004

AbstractWe study pseudoholomorphic maps from a punctured Riemann surface into the symplectization of a contact manifold. A Fredholm theory yields the virtual dimension of the moduli spaces of such maps in terms of the Euler characteristic of the Riemann surface and the asymptotics data given by the periodic solutions of the Reeb vector field associated to the contact form. The transversality results establish the existence of additional structure for these spaces. To be more precise, we prove that these spaces are generically smooth manifolds, and therefore their virtual dimension coincides with their actual dimension. © 2004 Wiley Periodicals, Inc.
Gender differences in GAD antibody – positive diabetes mellitus in relation to age at onset, C‐peptide and other endocrine autoimmune diseases
Authors: Lindholm Eero , Hallengren Bengt , Agardh Carl‐David 
Published: March 2004

AbstractBackgroundFemales have an increased incidence of autoimmune diseases. However, no gender difference in the incidence of type 1 diabetes is found. The frequency of antibodies against glutamic acid decarboxylase (GADA) in diabetes mellitus depends on age at diagnosis and also gender. Several studies have shown that high GADA levels can predict future β‐cell failure and need for insulin treatment. The aim of this study was to investigate possible gender differences in relation to GADA levels, fasting plasma C‐peptide levels and frequency of other autoimmune endocrine diseases in GADA‐positive patients with different age at diabetes diagnosis.MethodsGADA were screened in 4974 patients from a local diabetes registry (Diabetes 2000), and plasma C‐peptide was measured and a history of other autoimmune endocrine diseases was recorded. Of these patients, 822 were GADA positive and were further divided into four groups depending on the age at diagnosis of diabetes; Group 1: <20 years, Group 2: 20–39 years, Group 3: 40–59 years and Group 4: ≥60 years.ResultsFemale patients in Group 3 had lower fasting plasma C‐peptide levels (median 0.21[0.00–0–56] vs. 0.41[0.00–0.73] nmol/L, p = 0.02), higher GADA levels (median 7 [4–9] vs. 5 [2–7] Arbitrary Unit (AU), p = 0.0003) and higher frequency of other autoimmune endocrine diseases (22.4 vs. 5.3%, p = 0.0001) than male patients. In a stepwise logistic regression analysis, diabetes duration (p < 0.000001), high GADA levels (Exp (B) 3.68 CI 1.69–7.98, p = 0.001) and low BMI (p = 0.00002) were associated with total β‐cell failure in Group 3.ConclusionsGADA‐positive female diabetic patients with an age at diagnosis between 40 and 59 years have higher GADA levels and a more severe loss of β‐cell function than male patients with the same age at diagnosis. This could be due to the effect of sex steroids and/or GnRH on the regulation of the immune system. Female patients with high GADA levels also had a high prevalence of other autoimmune endocrine diseases, especially autoimmune thyroid disease, which further emphasises the need for screening of thyroid function in female patients with high GADA levels. Copyright © 2004 John Wiley & Sons, Ltd.
Calcium‐dependent mitochondrial permeability transition is augmented in the kidney of Goto‐Kakizaki diabetic rat
Authors: Oliveira Paulo J. , Esteves Telma C. , Seiça Raquel , Moreno António J. M. , Santos Maria S. 
Published: March 2004

AbstractBackgroundRenal disease associated with diabetes mellitus is a major problem among diabetic patients. The role of mitochondria in the pathogenesis of diabetes has received a large amount of attention in the last years, but many aspects of this subject are still poorly understood. In the present study, we studied the susceptibility of the mitochondrial permeability transition (MPT) on kidney mitochondria from the Goto‐Kakizaki (GK) rat, an animal model featuring physiological and pathological alterations characteristic of type 2 diabetes.MethodsKidney mitochondria were isolated by differential centrifugations; mitochondrial electric transmembrane potential and calcium loading capacity were evaluated with a TPP+‐selective electrode and with a calcium‐sensitive fluorescent probe. Coenzyme Q9, Q10 and vitamin E were evaluated by high‐performance liquid chromatography (HPLC).ResultsKidney mitochondria from the diabetic animals had an increased susceptibility to the induction of the MPT by calcium. We observed a loss of calcium‐loading capacity and a higher calcium‐induced mitochondrial depolarization. Vitamin E and coenzyme Q9 were also increased in kidney mitochondria from GK rats.ConclusionsThe results show an enhanced MPT activation in kidney mitochondria from GK rats, which lead us to suggest that this condition may be one major alteration triggered by chronic diabetes in kidney cells, ultimately leading to cell dysfunction. Copyright © 2004 John Wiley & Sons, Ltd.
Genetic prediction of type 1 diabetes in a population with low frequency of HLA risk genotypes and low incidence of the disease (the DIABFIN study)
Authors: Buzzetti R. , Galgani A. , Petrone A. , Del Buono M. L. , Erlich H. A. , Bugawan T. L. , Lorini R. , Meschi F. , Multari G. , Pozzilli P. , Locatelli M. , Bottazzo G. , Di Mario U. 
Published: March 2004

AbstractBackgroundTo develop a sensitive, specific screening strategy for predicting genetic risk for type 1 diabetes mellitus (T1DM) in the low‐incidence continental Italian population, and to define with this tool, a cohort of high‐to‐moderate risk infants for an immunological follow‐up study aimed at identifying environmental risk factors for T1DM.Methods4855 newborns in three regions of continental Italy were screened for T1DM HLA‐DRB1‐DQB1 risk genotypes using a reverse line blot typing method. Risk classification was based on odds ratios (OR) found in a preliminary case–control study (356 T1DM patients, 412 controls). Screening efficiency was optimized by allele subtyping.ResultsScreening for well‐known T1DM susceptibility genotypes [DRB1*03/*04‐DQB1*0302; DRB1*03/*03; DRB1*04/*04‐DQB1*0302; DRB1*04‐DQB1*0302/X where X ≠ DRB1*03, DRB1*04‐DQB1*0302, DQB1*0602 or DQB1*0603] was associated with <60% sensitivity due to their low frequencies in the general Italian population. Inclusion of an additional genotype from which protective DRB1 and DQB1 alleles had been excluded [DRB1*03/X° where DQB1 ≠ *0301, *0503, *0602, or *0603 and X° ≠ DRB1*03, DRB1*04‐DQB1*0302 or DRB1*07] increased screening sensitivity to 75% (specificity: 85%). Among 4855 newborns, we have found the high‐risk genotype [DRB1*03/*04‐DQB1*0302; estimated absolute risk (AR) 1/23] to be present in only 0.9%. The moderate‐risk genotypes were found in 13.8% of newborns (estimated AR 1/177).ConclusionsRisk classification must be tailored to the characteristics of the individual population, in particular, the allelic frequencies in the background population and T1DM prevalence. We have developed a screening strategy with good levels of sensitivity that should prove effective for use throughout the Italian peninsula. Copyright © 2004 John Wiley & Sons, Ltd.
Evidence for a vicious cycle of exercise and hypoglycemia in type 1 diabetes mellitus
Authors: Ertl A. C. , Davis S. N. 
Published: March 2004

AbstractExercise is a cornerstone of diabetes management as it aids in glycemic control, weight management, reducing blood pressure, and improving the quality of life of patients. Unfortunately, owing to the complexity and difficulties of regulating exogenous insulin in a physiologic manner during exercise, physical activity often results in hypoglycemia in patients with type 1 diabetes mellitus (type 1 DM).When glucose levels fall below threshold glycemic levels, neuroendocrine, autonomic nervous system (ANS), and metabolic glucose counterregulatory mechanisms are activated. These hypoglycemic counterregulatory mechanisms in type 1 DM can be blunted irreversibly by disease duration or by acute episodes of prior stress. These reduced (or absent) counterregulatory responses result in a threefold increase in severe hypoglycemia when intensive glycemic control is implemented in type 1 DM 1. Much recent work has been focused on determining the in vivo mechanisms responsible for causing the increased incidence of severe hypoglycemia in type 1 DM. Studies from several laboratories have demonstrated the role played by episodes of antecedent hypoglycemia in producing blunted glucose counterregulatory responses during subsequent exposures of hypoglycemia.Until recently, the mechanisms responsible for exercise related hypoglycemia in type 1 DM have been attributed to relative or absolute increases of insulin levels or incomplete glycogen repletion after physical activity. Owing to the qualitative similarity of neuroendocrine, ANS, and metabolic responses to hypoglycemia and exercise, we have hypothesized that neuroendocrine and ANS counterregulatory dysfunction may also play an important role in the pathogenesis of exercise‐related hypoglycemia in type 1 DM. Vicious cycles can be created in type 1 DM, where an episode of hypoglycemia or exercise can feed forward to downregulate neuroendocrine and ANS responses to a subsequent episode of either stress, thereby creating further hypoglycemia (Figure 1). This article will review the recent work that has studied the contribution of counterregulatory dysfunction to exercise‐induced hypoglycemia in type 1 DM. Copyright © 2004 John Wiley & Sons, Ltd.
1. Reciprocal vicious cycles may be created in type 1 diabetes mellitus (type 1 DM), whereby an episode of hypoglycemia or exercise can feed forward to downregulate neuroendocrine and autonomic nervous system responses to a subsequent episode of either stress, thereby creating further hypoglycemiamagnified image1. Reciprocal vicious cycles may be created in type 1 diabetes mellitus (type 1 DM), whereby an episode of hypoglycemia or exercise can feed forward to downregulate neuroendocrine and autonomic nervous system responses to a subsequent episode of either stress, thereby creating further hypoglycemia
Memory effect of ferroelectric liquid crystal stabilized by polymer fibers
Authors: Murashige Takeshi , Fujikake Hideo , Ikehata Seiichiro , Sato Fumio 
Published: March 2004

AbstractWe investigated the bistable state of the molecular orientation of ferroelectric liquid crystal that is formed between micro‐polymer fibers, and demonstrated the occurrence of a memory effect when the smectic layer structure is corrected. In this study, we introduced high‐pretilt alignment layer and formed polymer fibers in the liquid crystal by using the photopolymerization phase separation method in order to make the creasing and bending of the layer in the direction of thickness unidirectional. In addition, we treated the composite film of the liquid crystal and the polymer fiber by applying an AC voltage in order to hold the cone axis of the liquid crystal molecule in a rubbing direction during the gradual cooling process in which the liquid crystal molecule tilt (phase transition from the smectic A phase to the smectic C* phase). The results of trial production confirmed an alleviation of the bending of the smectic layer in the horizontal plane and the occurrence of a memory effect, resulting in a minute distribution of bistable switching domains and a memory function involving area‐wise grayscale. © 2004 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 87(4): 16–24, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.10082
New design method for tapered buffer circuit with TIS (Trench‐Isolated Transistor using sidewall gate) and its application to high‐density DRAMs
Authors: Watanabe Shigeyoshi 
Published: March 2004

AbstractA new design method has been conceived for a buffer circuit using TIS. In the buffer circuit of a taper type with a fan‐out of 3 intended for driving a large load capacitance, a new design procedure is conceived that minimizes the pattern area without sacrificing characteristics such as power consumption. In the new design method, the “planar+TIS” method is employed, in which planar‐type transistors are used in the front stage of the buffer circuit while TIS‐type transistors are used in the latter stage. This design method is applied to a large‐capacity DRAM. Relative to the case in which conventional planar transistors are used, the chip area can be reduced by about 8% without sacrificing characteristics such as power consumption. © 2004 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 87(4): 9–15, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.10152
Fabrication of extended porous polymer films for aligning nematic liquid crystal
Authors: Kuboki Masashi , Fujikake Hideo , Murashige Takeshi , Sato Hiroto , Fujisaki Yosihide , Kawakita Masahiro , Kikuchi Hiroshi , Kurita Taichiro , Sato Fumio 
Published: March 2004

AbstractA method is proposed for fabricating extended porous polymer films for spatially aligning liquid crystals. By means of the successive biaxial extension method, polyolefin porous polymer films are extended to a great degree (10µm thick, porosity 72.4%). After the porous polymer films are filled with nematic liquid crystals, a liquid crystal cell is fabricated by attaching glass substrates. The extension factor is 2.4 times and 6 times along the two orthogonal directions. As a result of observation by a polarization microscope, it is recognized that the liquid crystal molecules are aligned along the extension direction within the porous film. An optical modulation function using the birefringence of the liquid crystal is observed on application of a voltage. Unlike the conventional rubbing orientation process, the present scheme does not generate any static electricity or fine dust. Further, high‐temperature baking of the alignment layer is not necessary. Orientation processing of liquid crystals is possible with the substrate maintained at room temperature. © 2004 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 87(4): 1–8, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.10164
A neural network system composed of 1000 neurons and 1 million 7‐bit synapses
Authors: Hirai Yuzo , Ochiai Tatsuo , Yasunaga Moritoshi 
Published: March 2004

AbstractA pulse‐density‐type digital neural network system is developed in which digital circuits are used and all neurons operate asynchronously. The system is hardware of a scale in which 1008 neurons are mutually coupled through more than 1 million synapses with 7‐bit precision. The scale is the largest in the world. The system has the feature that the operation of the individual neuron follows a nonlinear first‐order differential equation, although digital circuits are used. Consequently, it is a system that can solve a 1000‐dimensional system of nonlinear differential equations in continuous time and in parallel. In order to realize the physical mutual couplings between more than 1000 neurons, the following simplifications are applied. The number of signal lines is reduced through the use of pulse density. The precision of the synaptic coupling coefficient is maintained as 7 bits. Spatial summation of the synaptic outputs is realized by using a pulse OR circuit. In spite of these simplifications, a discrimination experiment on the handwritten numerals using the nearest‐neighbor method shows that the proposed method is comparable to that of a workstation with floating‐point arithmetic. This system is connected to the Internet and can be accessed from any part of the world. The home page address ishttp://www.viplab.is.tsukuba.ac.jp/. © 2004 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 87(4): 34–43, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.20069
Automatic prank call rejection system for home country direct based on speech recognition technology
Authors: Kuroiwa Shingo , Naito Masaki , Nakamura Makoto , Sakayori Shin'ichi , Mukasa Takeshi 
Published: March 2004

AbstractA system that automatically rejects prank calls coming through home country direct from abroad, which is one of the international telephone services, is presented in this paper. Home country direct is a service whereby a user can use international telephone services in his/her native language by directly accessing home country's international station operators. Since this service does not require fees for calling operators, prank calls made by children from abroad pose a problem. Thus, an “automatic prank call rejection system” that determines a legitimate user by instructing him in Japanese to say a specific word, and determining him to be a legitimate user if he repeats this word correctly or determining the call to be a prank call otherwise has been developed. When this system was applied to commercial services, it rejected 94.7% of prank calls. Legitimate users erroneously rejected constituted 0.8%. It has been confirmed that erroneously rejected legitimate users ended up being connected by repeating the word correctly ultimately by hanging up the phone and redialing a number of times. This system has been found to reject about 10,000 prank calls a day when applied to the operations of the KDD International Telephone Center since March 1996. © 2004 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 87(4): 44–52, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.20070