bluuebunny/crossref_metadata_2025_split huggingface dataset:
THE STRUCTURE OF EQUIVALENCE CLASSES
Authors: Fields Lanny , Verhave Thom 
Published: March 2006

The structure of equivalence classes can be completely described by four parameters: class size, number of nodes, the distribution of “singles” among nodes, and directionality of training. Class size refers to the number of stimuli in a class. Nodes are stimuli linked by training to at least two other stimuli. Singles are stimuli linked by training to only one other stimulus. The distribution of singles refers to the number of singles linked by training to each node. Directionality of training refers to the use of stimuli as samples and as comparison stimuli in training. These four parameters define the different ways in which the stimuli in a class can be organized, and thus provide a basis for systematically characterizing the properties of stimuli in a given equivalence class. The four parameters can also be used to account for the development of individual differences that are commonly characterized in terms of “understanding” and connotative meaning.Methods are described for generating all possible combinations of parameter values, and a formula is introduced which specifies all of the parameter values for an equivalence class. Its utility for interrelating experimental procedures is demonstrated by analyzing a number of representative experiments that have addressed equivalence‐class formation.
Diffraction Methods in Inorganic Chemistry
Authors: Howard Judith A. K. , Batsanov Andrei S. 
Published: March 2006

AbstractX‐ray diffraction is by far the largest source of information on crystal and molecular structures and (at high precision) can reveal fine details of the electron density distribution. Neutron diffraction is indispensable for special tasks, for example, locating hydrogen atoms and studying crystal dynamics and magnetic properties. After a brief introduction on crystal symmetry and diffraction physics, the article surveys the currently available instrumentation and practical techniques of diffraction experiments, of interpreting the structural data and assessing their quality, with an emphasis on recent progress in technology (synchrotron radiation, area detectors, low‐ and high‐temperature, and high‐pressure experiments), software (direct phasing, dealing with twinning and incommensurate phases), and data storage (crystallographic databases).
Dioxygen & Related LigandsBased in part on the article Dioxygen & Related Ligands by Rebecca R. Conry & Kenneth D. Karlin which appeared in theEncyclopedia of Inorganic Chemistry, First Edition.
Authors: Conry Rebecca R. 
Published: March 2006

AbstractMetal–dioxygen interactions are important in the activation of dioxygen by aerobic organisms and in other processes that utilize dioxygen, for instance, in catalytic oxygenation reactions. Most d‐block metals have been found to interact with dioxygen and many dioxygen‐containing complexes have been isolated. A number of binding modes have been found in these complexes, including the simple binding of one O2molecule to one metal center and systems where the O2moiety bridges two or more metal ions. Some reduction of dioxygen occurs upon binding; thus, these complexes are generally regarded as containing superoxide (one‐electron reduced) or peroxide (two‐electron reduced) ligands, which are typically spectroscopically distinguished. In general, superoxo complexes exhibit υ(OO) in their infrared or Raman spectra between about 960 and 1200 cm−1and usually contain planar metal2–O2units for dinuclear complexes, whereas peroxide complexes result in υ(OO) between about 650 and 950 cm−1and the dinuclear complexes typically have nonplanar metal2–O2units. Examples of superoxo and peroxo complexes for the different binding modes are discussed, including the discovery that some dinuclear metal–dioxygen complexes [M(O2)M; M = metal] are in equilibrium with bis‐μ‐oxo complexes [M(O)2M; i.e. the OO bond is no longer present].
Nitrogen: Inorganic ChemistryBased in part on the article Nitrogen: Inorganic Chemistry by Harry H. Sisler which appeared in theEncyclopedia of Inorganic Chemistry, First Edition.
Authors: Hammerl Anton , Klapötke Thomas M. 
Published: March 2006

AbstractThe chemistry of nitrogen and its compounds with hydrogen, oxygen, and halogens is discussed in this article. The high stability of the nitrogen–nitrogen triple bond in dinitrogen in comparison with nitrogen–nitrogen single or double bonds makes polynitrogen compounds promising, highly energetic materials. Recently, several new polynitrogen species have been detected experimentally and salts of the polynitrogen cation N5+have been isolated in bulk. Salts of the azide anion N3−are already used as highly energetic materials.Binary compounds of nitrogen and hydrogen include ammonia, hydrazine, and several metastable species with nitrogen–nitrogen bonds. Ammonia, which is the starting material for all industrially produced nitrogen compounds, is probably the most important industrial chemical. Most of the ammonia produced is used as fertilizer, whereas hydrazine is used as an energetic material.The monomeric nitrogen oxides are among the most simple odd‐electron molecules and play an important role in the chemistry of the atmosphere. In combustion engines, huge amounts of nitric oxide are formed, which influence the ozone cycle both in the troposphere and in the stratosphere. Nitric oxide is a chemical messenger in biological systems and it helps to regulate a diverse array of physiological processes, such as neurotransmission, blood pressure and blood clot prevention.Oxoacids of nitrogen include hydroxylamine, nitrous acid, and nitric acid. Nitric acid is a major industrial chemical, which is primarily used for nitrate fertilizer production. Hydroxylamine is a starting material for the production of polyamide synthetics.Chlorine, bromine, and iodine halogen nitrogen compounds include halogensubstituted derivatives of ammonia, hydrazine, and diimine. They are unstable species that decompose to molecules in excited states. Nitrogen fluorides are thermodynamically more stable than the other nitrogen halides.Ternary compounds of nitrogen, oxygen, and halogens include nitrosyl‐ and nitrylhalides as well as the halogen nitrates. The stability of these compounds decreases from fluorine to iodine.
Scandium, Yttrium & the Lanthanides: Inorganic & Coordination Chemistry
Authors: Cotton Simon A. 
Published: March 2006

AbstractThe lanthanides are a block of elements with atomic numbers 57–71, which exhibit subtle gradations in their chemical properties, since the ionic radii gradually decrease across the series (the ‘lanthanide contraction’). In reactivity, they resemble the group 2 elements, but are much more diverse; although the aqueous chemistry is essentially that of the +3 oxidation state, the +2 and +4 states are significant for certain metals. The 4f orbitals are well shielded and play little part in lanthanide chemistry, so lanthanides have virtually no chemistry in the zerovalent state and do not form multiple bonds to atoms like N and O. As with the transition metals, lanthanide ions usually have a partly filled subshell (4f), but, in contrast, crystal‐field splittings are weak compared with spin‐orbit coupling, and thus spectroscopic properties of lanthanide complexes strongly resemble those of the free ions; sharp f‐f‐transitions in both excitation and emission spectra confer valuable properties upon certain ions. Lanthanides form a full range of binary compounds with nonmetals, especially the group 16 and 17 elements. The halides LnX3, in particular, demonstrate both the high coordination numbers and the lanthanide contraction. The complex chemistry in aqueous solution is dominated by ‘hard’ donors, especially oxygen‐based ligands (lanthanide ions have very high hydration energies), but ligands with other donor atoms, such as nitrogen, form stable complexes in nonaqueous solvents. The lanthanide aqua ion has a coordination number of 9, decreasing to 8 for the later metals; higher coordination numbers of up to 12 are possible with ligands with a small ‘bite’, such as nitrate. Many complexes exist of oxygen‐donor ligands such as THF and phosphine oxides, with formulae of the type [La(THF)nCl3] (n, e.g. 3, 4) and [Ln(R3PO)n(NO3)3] (n, e.g. 2, 3). Diketonate complexes are important; stable adducts with molecules like polyethers are often volatile enough to be MOCVD precursors. Bi‐ and tridentate N‐donor ligands like bipy and terpy form high coordination number complexes that often exhibit subtle variations in structure with choice of lanthanide and solvent. Low‐coordination numbers are achieved using very bulky amide, alkoxide, and alkyl ligands, when values as low as 2 and 3 are possible. Polyaminepolycarboxylic acids such as EDTA and DTPA form very stable complexes that are highly important in separating mixtures of the lanthanides and also, in the case of [Gd(DTPA)(H2O)]3−, as a contrast enhancing agent in MRI, one of an increasing number of applications that rely upon their electronic and magnetic properties. Yttrium has very similar properties to the later lanthanides, but scandium is significantly smaller. Although the first 3d metal, scandium is not a transition metal, but has significantly different properties, partly on account of its slightly greater size, forming complexes with higher coordination numbers (e.g. the aqua ion [Sc(H2O)7]3+). Its developing chemistry is that of a slightly smaller version of lutetium.
Periodic Table: Historical Aspects
Authors: Rouvray Dennis H. 
Published: March 2006

AbstractThe periodic table effectively embodies a summary of the entire realm of chemistry. Because of this, the table is one of the most important classifications of the natural world. However, the table could not be constructed before the concept of the chemical element had been clarified in the mid‐seventeenth century. Additionally, an ordering of the elements was not possible until a method had been devised of associating a number with each element, that is, the atomic weight or, nowadays, the atomic number. The periodic table evolved gradually over half a century, starting with the ordered triads of elements of Döbereiner in 1817 and culminating in the publication of the 63‐element table of Mendeleev in 1869. After its appearance, the table was confronted with several problems, including the accommodation of the noble gases, allowance for the existence of elemental isotopes, and the placement of the lanthanide and actinide elements. In spite of many such challenges, the periodic table has stood the test of time and is now widely viewed as one of the greatest achievements of the human intellect.
Nonimmune idiopathic hydrops fetalis and congenital lymphatic dysplasia
Authors: Bellini Carlo , Hennekam Raoul C.M. , Boccardo Francesco , Campisi Corradino , Serra Giovanni , Bonioli Eugenio 
Published: February 2006

AbstractSix newborns that presented at birth with nonimmune hydrops fetalis and for whom no cause could be found were investigated for the presence of lymphatic dysplasia. Careful analysis led to findings of some degree of lymphatic dysplasia in all patients. This suggests that lymphatic dysplasia may represent at least part of the causes that are responsible for the “idiopathic” form of nonimmune hydrops fetalis. Carefully searching for lymphatic dysplasia in these patients, and if indicated in their relatives, as well as establishing the exact nature of the lymphatic dysplasia must be carried out so as to provide proper genetic counseling to families with nonimmune hydrops. © 2006 Wiley‐Liss, Inc.
The von Hippel–Lindau (VHL) germline mutation V84L manifests as early‐onset bilateral pheochromocytoma
Authors: Abbott Mary‐Alice , Nathanson Katherine L. , Nightingale Simon , Maher Eamonn R. , Greenstein Robert M. 
Published: February 2006

AbstractVon Hippel–Lindau (VHL) disease is a heritable tumor susceptibility syndrome caused by germline mutations in the VHL gene. The types of tumor that can occur in affected individuals include retinal and central nervous system hemangioblastoma, renal cell carcinoma, pheochromocytoma, and others. The pattern of tumor types that develops in a VHL‐affected family defines the clinical subtype (1, 2A, 2B, 2C). Generally, it is difficult to accurately predict an individual's clinical phenotype based on their VHL mutation. However, in a few specific VHL mutations, a strong genotype–phenotype correlation has been established. We report here on the clinical findings in individuals from three unrelated families with a V84L VHL germline mutation, and present follow‐up information regarding the only other reported family with this missense mutation. In each of these four families, the major clinical manifestation of VHL disease is multiple early‐onset pheochromocytomas (VHL type 2C). This series of eight patients strengthens the correlation between the V84L mutation and the VHL type 2C phenotype, and improves our ability to provide prognostic and management recommendations for similarly affected individuals. © 2006 Wiley‐Liss, Inc.
NTNG1 mutations are a rare cause of Rett syndrome
Authors: Archer Hayley L. , Evans Julie C. , Millar David S. , Thompson Peter W. , Kerr Alison M. , Leonard Helen , Christodoulou John , Ravine David , Lazarou Lazarus , Grove Lucy , Verity Christopher , Whatley Sharon D. , Pilz Daniela T. , Sampson Julian R. , Clarke Angus J. 
Published: February 2006

AbstractA translocation that disrupted the netrin G1 gene (NTNG1) was recently reported in a patient with the early seizure variant of Rett syndrome (RTT). The netrin G1 protein (NTNG1) has an important role in the developing central nervous system, particularly in axonal guidance, signalling and NMDA receptor function and was a good candidate gene for RTT. We recruited 115 patients with RTT (females: 25 classic and 84 atypical; 6 males) but no mutation in the MECP2 gene. For those 52 patients with epileptic seizure onset in the first 6 months of life, CDKL5 mutations were also excluded. We aimed to determine whether mutations in NTNG1 accounted for a significant subset of patients with RTT, particularly those with the early onset seizure variant and other atypical presentations. We sequenced the nine coding exons of NTNG1 and identified four sequence variants, none of which were likely to be pathogenic. Mutations in the NTNG1 gene appear to be a rare cause of RTT but NTNG1 function demands further investigation in relation to the central nervous system pathophysiology of the disorder. © 2006 Wiley‐Liss, Inc.
The natural history of trisomy 12p
Authors: Segel Reeval , Peter Inga , Demmer Laurie A. , Cowan Janet M. , Hoffman Jodi D. , Bianchi Diana W. 
Published: February 2006

AbstractTrisomy of the short arm of chromosome 12 is a rare chromosomal anomaly, with an estimated incidence of 1/50,000 births. It may present as a pure trisomy (complete or incomplete), as mosaic trisomy, or with other chromosomal abnormalities. Little is known from prior reports about the natural history and life expectancy of these individuals. In this study we describe the long‐term outcome and the differences between patients with mosaic trisomy 12p compared to patients with complete trisomy. We present a series of 16 patients with trisomy 12p; 6 of them are older than 10 years. Most patients were born at term with normal or above normal birth weight. Seven were born with congenital anomalies, but no single anomaly was present in more than one individual. A clear and consistent dysmorphic facial pattern was apparent in all of the subjects. Most patients over 7 years old had a seizure disorder. All individuals exhibited developmental delay with speech affected more severely than motor skills. Six patients were described as “being social.” Six had severe behavioral problems, and seven had significant sleep disturbances. Facial features of the three adult patients were different than the younger individuals. We show here that the outcome for patients with mosaic trisomy 12p is better than the outcome in complete trisomy 12p or in trisomy 12p with other chromosomal anomalies. We also provide recommendations for the long‐term follow‐up of patients with trisomy 12p. © 2006 Wiley‐Liss, Inc.
Orofaciodigital syndrome with cerebral dysgenesis
Authors: Lesca Gaetan , Fallet‐Bianco Catherine , Plauchu Henri , Vitrey Danielle , Verloes Alain , Attia‐Sobol Jocelyne 
Published: February 2006

AbstractOrofaciodigital syndromes (OFD) are a group of diseases classified according to the phenotype and the mode of inheritance. We report on a fetus presenting with some features of the OFDs but with additional global cerebral dysgenesis. Ultrasonography at 19 weeks of pregnancy disclosed hypoplasia of the cerebral hemispheres with a large intrahemispheric cyst, as well as dysmorphic facial features and brachy‐syndactyly IV–V. Fetal brain MRI confirmed these features and disclosed additional morphological anomalies: Agenesis of the vermis, complete agenesis of the corpus callosum, pachygyria of the left hemisphere. Pathological examination showed a disproportionate fetus with large head and short limbs. Dysmorphic features included hypertelorism, broad nasal root, long philtrum, severe micrognathia, microstomia, cleft palate, and lobulated tongue. Radiographs showed distal malformations of the four limbs. Neuropathological examination showed a severe disturbance of the architecture of both hemispheres, more severe on the right side, with four cystic structures located between the hemispheres. Olfactory stalks, mammillary bodies, and midline structures were absent. Cerebellum and brainstem were hypoplastic. On the right hemisphere as on most part of the left one, microscopic findings displayed a complete disruption of the developing mantle with disturbance of the neuronal migration. The present fetus fulfilled the diagnosis of OFD syndrome: Dysmorphic features, cleft palate and lobulate tongue and polysyndactylies of the feet and hands. The cerebral involvement would make it closer to OFD type VI, but brain malformations were far more severe in the present case, with complex and generalized cortical dysgenesis, evoking a disturbance occurring at a very early stage of the embryogenesis. © 2006 Wiley‐Liss, Inc.
Molecular characterization of an 11q interstitial deletion in a patient with the clinical features of Jacobsen syndrome
Authors: Wenger Sharon L. , Grossfeld Paul D. , Siu Benjamin L. , Coad James E. , Keller Frank G. , Hummel Marybeth 
Published: February 2006

AbstractThe 11q terminal deletion disorder or Jacobsen syndrome is a contiguous gene disorder. It is characterized by psychomotor retardation, cardiac defects, blood dyscrasias (Paris‐Trousseau syndrome) and craniofacial anomalies. We report on a female patient with an approximately 10 Mb interstitial deletion with many of the features of Jacobsen syndrome: A congenital heart defect, dysmorphic features, developmental delay, and Paris‐Trousseau syndrome. The karyotype of the patient is 46,XX,del(11)(q24.1q24.3). The interstitial deletion was confirmed using FISH probes for distal 11q, and the breakpoints were characterized by microarray analysis. This is the first molecularly characterized interstitial deletion in a patient with the clinical features of Jacobsen syndrome. The deletion includes FLI‐1, but not JAM‐3, which will help to determine the critical genes involved in this syndrome. © 2006 Wiley‐Liss, Inc.
A new syndrome of microtia with mixed type hearing loss, renal agenesis, and multiple skeletal anomalies
Authors: Demir Yavuz , Samli Hale , Yucel Aylin , Yilmaz M. Deniz , Haktanir Nurten Turhan , Maralcan Gokhan , Solak Mustafa 
Published: February 2006

AbstractWe report on a 17‐year‐old man who presented with unreported combination of right sided microtia and preauricular skin tag with conductive hearing loss, unilateral renal agenesis, partial syndactyly of forth and fifth metacarpals, multiple tarsal coalitions, absent toe, and hypoplastic tibia and fibula. Radiological and clinical findings did not match with the previously described syndromes with the type of anomalies seen in the case. We propose that this represents a new syndrome. © 2006 Wiley‐Liss, Inc.
Experimental and numerical study of heterogeneous pressure‐temperature‐induced lethal and sublethal injury of Lactococcus Lactis in a medium scale high‐pressure autoclave
Authors: Kilimann K.V. , Kitsubun P. , Delgado A. , Gänzle M.G. , Chapleau N. , Le Bail A. , Hartmann C. 
Published: March 2006

AbstractThe present contribution is dedicated to experimental and theoretical assessment of microbiological process heterogeneities of the high‐pressure (HP) inactivation of Lactococcus lactis ssp. cremoris MG 1363. The inactivation kinetics are determined in dependence of pressure, process time, temperature and absence or presence of co‐solutes in the buffer system namely 4 M sodium chloride and 1.5 M sucrose. The kinetic analysis is carried out in a 0.1‐L autoclave in order to minimise thermal and convective effects. Upon these data, a deterministic inactivation model is formulated with the logistic equation. Its independent variables represent the counts of viable cells (viable but injured) and of the stress‐resistant cells (viable and not injured). This model is then coupled to a thermo‐fluiddynamical simulation method, high‐pressure computer fluid dynamics technique (HP‐CFD), which yields spatiotemporal temperature and flow fields occurring during the HP application inside any considered autoclave. Besides the thermo‐fluiddynamic quantities, the coupled model predicts also the spatiotemporal distribution of both viable (VC) and stress‐resistant cell counts (SRC). In order to assess the process non‐uniformity of the microbial inactivation in a 3.3‐L autoclave experimentally, microbial samples are placed at two distinct locations and are exposed to various process conditions. It can be shown with both, experimental and theoretical models that thermal heterogeneities induce process non‐uniformities of more than one decimal power in the counts of the viable cells at the end of the treatment. © 2006 Wiley Periodicals, Inc.
Design, Synthesis, and Characterization of Conifer‐Shaped Dendritic Architectures
Authors: Newkome George R. , Kotta Kishore K. , Moorefield Charles N. 
Published: March 2006

AbstractAn elongated structural design leading to more conical‐shaped dendritic architectures by using a combination of 1→3, 1→(2+1), and 1→(2+1 Me) C‐branched monomers is presented. Synthesis of the conifer‐shaped macromolecule was achieved by reaction between isocyanate 20 and amine 26 in dry CH2Cl2. A resultant extended focal adamantane‐modified dendron was deprotected to generate the water‐soluble product, which was subsequently complexed with β‐cyclodextrin in D2O to create the desired tree‐like product. Host–guest interactions of the adamantane moiety with the β‐cyclodextrin cavity were monitored by 1H NMR spectroscopy. All monomers, key intermediates, and final products were fully characterized by 1H and 13C NMR spectroscopy, ESI or MALDI‐TOF mass spectrometry, and IR spectroscopy.
Synthesis, Crystal Structure, and Vibrational and Optical Spectroscopy of the First Quaternary Alkaline‐Earth Rare Earth Thiophosphates Ba3Ln2[P4S16] (Ln: Gd—Er).
Authors: Klawitter Yvonne , Bensch Wolfgang , Wickleder Claudia 
Published: March 2006

AbstractChemInform 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.
Bismuth Triflate Catalyzed Mukaiyama Aldol Reaction in an Ionic Liquid.
Authors: Ollevier Thierry , Desyroy Valerie , Debailleul Blandine , Vaur Sophie 
Published: March 2006

AbstractChemInform 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.