bluuebunny/crossref_metadata_2025_split huggingface dataset:
Molecular homochirality and the parity‐violating energy difference. A critique with new proposals
Authors: Chandrasekhar Sosale 
Published: December 2007

AbstractPrevious proposals for the origin of molecular homochirality, based on the effect of the weak neutral current (WNC) on enantiomers, and the amplification of the resultant parity‐violating energy difference (PVED), are possibly flawed. The additive amplification of PVED in crystals and polymers (“Yamagata hypothesis”) cannot lead to detectable levels of optical activity, the original theory apparently overestimating PVED by a factor equal to Avogadro's number. An alternative theory based on the irreversible and spontaneous evolution of a dynamically fluctuating system is apparently impractical. However, the nonlinear amplification of PVED via autocatalytic polymerization may be possible as indicated by a simplified physico‐chemical approach. This may also occur during crystallization and melting, and form the basis of the second order asymmetric transformation. (Thus, reported differences in the melting points of enantiomers in several cases may well be real). Also, the preponderance of racemic compounds over conglomerates may be based on the destabilization of the conglomerate by the action of the WNC on the crystalline lattice. The WNC may also be involved in the anomalous scattering of X‐rays, which possibly arises from their circular polarization: the current theory would need to be revised accordingly. Chirality, 2008. © 2007 Wiley‐Liss, Inc.
Resource allocation for statistical quality of service provision in buffered crossbar switches
Authors: Duan Qiang , Daigle John N. 
Published: December 2007

AbstractThe buffered crossbar switch is a promising switching architecture that plays a crucial role for providing quality of service (QoS) in computer networks. Sufficient amount of resources—bandwidth and buffer space—must be allocated in buffered crossbar switches for QoS provision. Resource allocation based on deterministic QoS objectives might be too conservative in practical network operations. To improve resource utilization in buffered crossbar switches, we study the problem of resource allocation for statistical QoS provision in this paper. First, we develop a model and techniques for analyzing the probabilistic delay performance of buffered crossbar switches, which is described by the delay upper bound with a prescribed violation probability. Then, we determine the required amounts of bandwidth and buffer space to achieve the probabilistic delay objectives for different traffic classes in buffered crossbar switches. In our analysis, we apply the effective arrival envelope to specify traffic load in a statistical manner and characterize switch service capacity by using the service curve technique. Instead of just focusing on one specific type of scheduler, the model and techniques developed in this paper are very flexible and can be used for analyzing buffered crossbar switches with a wide variety of scheduling algorithms. Copyright © 2007 John Wiley & Sons, Ltd.
Temporal–spatial ablation of neural crest in the mouse results in cardiovascular defects
Authors: Porras Diego , Brown Christopher B. 
Published: December 2007

AbstractNeural crest cells are thought to play a critical role in human conotruncal morphogenesis and dysmorphogenesis. Much of our understanding of the contribution of neural crest to cardiovascular patterning comes from ablation and transplantation experiments in avian species. Although fate mapping experiments in mice suggests a conservation of function, the functional requirement for neural crest in cardiovascular development in mammals has not been formally tested. We used a novel two component genetic system for the temporal–spatial ablation of neural crest in the mouse. Affected embryos displayed a spectrum of cardiovascular outflow tract defects and aortic arch patterning abnormalities. We show that the severity of the cardiovascular phenotype is directly related to the level and extent of neural crest ablation. This is the first report of cardiac neural crest ablation in mammals, and it provides important insight into the role of the mammalian neural crest during cardiovascular development. Developmental Dynamics 237:153–162, 2008. © 2007 Wiley‐Liss, Inc.
Biological spacetime and the temporal integration of functional modules: A case study of dento–gnathic developmental timing
Authors: Boughner Julia C. , Hallgrímsson Benedikt 
Published: December 2007

AbstractFor the individual, coordination between tooth and jaw development is important to proper food acquisition and ingestion later in life. Among and within species, variation in dental and gnathic size, shape, and, in the case of teeth, number, must be mutually accommodating and functionally compatible. For these reasons, the development and evolution of these two systems should be closely integrated. Furthermore, the timing of dental development correlates tightly with life history events such as weaning. This correlation hints at a central regulation of the developmental timing of multiple systems that have tandem effects on physiology and behaviour. Important work on embryonic oral development continues to tease apart the molecular mechanisms that pattern jaw identity and establish tooth morphology and position in the alveolar bone. Still very poorly understood is what underlies rates and periods of gene activity such that pre‐ and postnatal tooth and jaw development are coordinated. Recent literature suggests at least some level of autonomy between permanent tooth and mandibular ontogenetic timing. However, whether the timing of these various signaling pathways is directly regulated or is an outcome of the pathways themselves is untested. Here, we review what is currently known about the embryonic signaling pathways that regulate tooth and jaw development in the context of time rather than space, as has been traditional. We hypothesize that the timing of mandibular and dental development is not directly mediated by a common factor but is an indirect outcome of strong selection for coordinated molecular pathways and growth trajectories. The mandible and lower jaw dentition is a powerful model with which to investigate the mechanisms that facilitate morphological change—in this case, the development and evolution—of organs that are closely integrated in terms of function, space and time. Developmental Dynamics 237:1–17, 2008. © 2007 Wiley‐Liss, Inc.
From Interwoven to Noninterpenetration: Crystal Structural Motifs of Two New Manganese–Organic Frameworks Mediated by the Substituted Group of the Bridging Ligand
Authors: Fu Zhiyong , Yi Jianglong , Chen Yuan , Liao Shijun , Guo Ning , Dai Jingcao , Yang Guodong , Lian Yunxia , Wu Xintao 
Published: December 2007

AbstractThe respective reactions of the MnII ion with the homologous ligands 2‐aminoterephthalic acid and terephthalic acid afforded two novel manganese–organic compounds, [Mn(2‐atp)(bipy‐eta)0.5]n (1) and {[Mn(tp)(bipy‐eta)1.5]·2H2O}n (2). These two compounds were characterized by IR spectroscopy, elemental analysis, and single‐crystal X‐ray diffraction. Compound 1 (C14H11MnN2O4) belongs to the monoclinic C2 space group, Z = 4 [a = 11.9355(9) Å, b = 15.522(1) Å, c = 7.9542(6) Å, β = 112.591(2)°], whereas compound 2 (C26H26MnN3O6) belongs to the monoclinic P21/c space group, Z = 4 [a = 10.0330(3) Å, b = 11.9454(1) Å, c = 21.8640(5) Å, β = 92.842(2)°]. Both compounds have bimetallic blocks as basic units. With two bridging carboxylate groups, the Mn···Mn separation in compound 2 is 4.841 Å. By contrast, the distance of the Mn···Mn centers in compound 1 (with the first paddle‐like manganese core) is shortened to 3.058 Å by the bridging of four carboxylate groups, which suggests the existence of a Mn–Mn single bond. The paddle‐wheel clusters in compound 1 aggregate into a 3D modular framework that interpenetrates in a threefold manner. The binuclear units in 2 extend to a 3D network with a novel bilayer structural motif. The inclusion of the bipy‐eta molecules prevents the structure of 2 from being interwoven, and it thus adopts a noninterpenetrating arrangement. The results indicate that variations in the molecular self‐assembly are influenced by the substituted group in the bridging ligand.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Preparation of Brookite‐Type TiO2/Carbon Nanocomposite Electrodes for Application to Li Ion Batteries
Authors: Lee Du‐Hee , Park Jae‐Gwan , Jin Choi Kyoung , Choi Heon‐Jin , Kim Dong‐Wan 
Published: December 2007

AbstractThe increasing demand for portable energy has generated significant research interest in nanostructured electrode materials, because of their large interfacial contact area with the electrolyte and short path lengths for Li ion transport. To date, titanium dioxide (TiO2) has been widely investigated as an electroactive, Li‐insertion host. However, the lithium reactivity of brookite‐type TiO2 has rarely been addressed compared to the common polymorphs, anatase and rutile, because of the difficulties encountered in obtaining a phase‐pure brookite structure. Herein, we report on the simple synthesis of nanocrystalline brookite‐type TiO2 using titanium trichloride (TiCl3) and urea [(NH2)2CO]. The average size of the particles precipitated at 100 °C was ca. 10 nm. The brookite structure was stable up to 500 °C and was completely transformed to the rutile structure at 900 °C in an O2 atmosphere. We evaluated the electrochemical properties of each TiO2 powder heat‐treated sample at a preset temperature. Hybrid carbon/TiO2 nanocomposites with high conductivity were also fabricated using a stable suspension of multi‐walled carbon nanotubes (MWCNTs) in aqueous suspension with an appropriate surfactant and subsequent precipitation of TiO2. The carbon incorporation clearly improved the capacity retention of TiO2 upon cycling.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Two Photoluminescent Metal–Organic Frameworks Constructed from Cd3(μ3‐OH) Cluster or 1D Zn5(μ3‐OH)2(μ‐OH)2 Chain Units and In Situ Formed Bis(tetrazole)amine Ligands
Authors: Zheng Ling‐Ling , Li Hao‐Xiang , Leng Ji‐Dong , Wang Jing , Tong Ming‐Liang 
Published: December 2007

AbstractHydrothermal reactions of CdCl2·2.5H2O or ZnCl2, sodium dicyanamide, and sodium azide yield two interesting photoluminescent coordination polymers, namely, [Cd{Cd3(μ3‐OH)(dcadtzH)3(H2O)6}2] (1) and [Zn5(μ3‐OH)2(μ‐OH)2(dcadtz)2]·2H2O (2) [dcadtzH3 = bis(5‐tetrazolyl)amine], in which triangular [Cd3(μ3‐OH)]5+ cluster subunits in 1 and 1D [Zn5(μ3‐OH)2(μ‐OH)2]n6n+ chain subunits in 2 are linked by in situ generated bis(tetrazole)amine ligands to generate an interesting 2D coordination net and a 3D microporous metal–organic framework, respectively. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Lanthanide Formamidinates as Improved Catalysts for the Tishchenko Reaction
Authors: Zuyls Agustino , Roesky Peter W. , Deacon Glen B. , Konstas Kristina , Junk Peter C. 
Published: December 2007

AbstractThe tris(formamidinato)lanthanum(III) complexes [La(o‐TolForm)3(thf)2] [1; o‐TolForm = N,N′‐bis(o‐tolyl)formamidinate], [La(XylForm)3(thf)] [2; XylForm = N,N′‐bis(2,6‐dimethylphenyl)formamidinate], and [La(EtForm)3] [3, EtForm = N,N′‐bis(2,6‐diethylphenyl)formamidinate] are a new class of precatalysts for the Tishchenko reaction. Their catalytic activity is a result of their high Lewis acidity and the ease with which the ligand spheres can be interchanged. For the dimerization of benzaldehyde to give benzyl benzoate, which is a benchmark reaction, compound 1 is, to the best of our knowledge, the most active catalyst ever reported. On a preparative scale, the reaction can be performed in the absence of solvent. A range of aromatic, heteroaromatic, and aliphatic aldehydes was rapidly converted into the corresponding esters by using catalysts 1–3.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Low‐complexity fuzzy filter‐assisted turbo equalization for dispersive Rayleigh‐fading channels
Authors: Lain Jenn‐Kaie , Kuo Kun‐Huang , Zhang Liao Yuan‐Kai 
Published: December 2007

AbstractTurbo equalisation (TEQ) is an iterative detection and decoding technique that has been shown to be successful in mitigating the effects of intersymbol interference (ISI) introduced by partial response modems and by dispersive channels. In this paper, we propose a fuzzy filter‐assisted decision‐feedback equaliser (DFE)‐based TEQ scheme that not only is comparable in performance to the Jacobian radial basis function (RBF) DFE‐based TEQ but also is low‐complexity. The per iteration computation of both the fuzzy filter DFE TEQ using product inference and maximum defuzzification and the fuzzy filter DFE TEQ using minimum inference and maximum defuzzification is much lower than that of the Jacobian RBF DFE TEQ for binary phase‐shift keying (BPSK) modulation, 4 quadrature amplitude modulation (QAM), and 16 QAM. Notably, the computational complexity of the Jacobian RBF DFE TEQ is exponentially related to the feedforward order, but the fuzzy filter DFE TEQ using minimum inference and maximum defuzzification is independent of that. Previous TEQ research has shown that the Jacobian RBF DFE TEQ considerably reduces the computational complexity compared to the logarithmic maximuma posteriori(Log‐MAP) TEQ with similar performance. In this present study, the proposed fuzzy filter DFE TEQ further reduces the computational complexity with slight performance degradation in contrast to the Jacobian RBF DFE TEQ. With this, the materialisation of the TEQ scheme becomes more feasible. Copyright © 2007 John Wiley & Sons, Ltd.
Slot error rate performance of DH‐PIM with symbol retransmission for optical wireless links
Authors: Rajbhandari S. , Ghassemlooy* Z. , Aldibbiat N. M. 
Published: December 2007

AbstractIn this paper we introduce the dual‐header pulse interval modulation (DH‐PIM) technique employing a simple retransmission coupled with a majority decision detection scheme at the receiver. We analytically investigate the slot error rate (SER) performance and compare results with simulated data for the symbol retransmissions rates of three, four and five, showing a good agreement. We demonstrate that the proposed scheme significantly reduces the SER compared with the standard single symbol transmission system, with retransmission rate of five offering the highest code gain of ∼5 dB. Copyright © 2007 John Wiley & Sons, Ltd.
A palynological study of Galium L. (Rubiaceae) in Egypt and its systematic implication
Authors: Abdel Khalik K. , Abd El‐Ghani M. M. , Elkordy A. 
Published: December 2007

AbstractA pollen morphological investigation of eleven species and one subspecies of the genus Galium L. from Egypt were undertaken by using light microscope (LM) and scanning electron microscope (SEM). Pollen shape, size, exine ornamentation, number of apertures present powerful characters for distinguishing between species. The pollen grains were zonocolpate. The number of colpi ranges from 5 to 10. Their shape varies from prolate spheroidal, oblate spheroidal, spheroidal to suboblate. Three groups can be distinguished based on the size pollen grains. It was found used to distinguish between closely related species G. aparine and G. spurium and between G. tricornutum and G. ceratopodum. Two different types of exine ornamentation were recognized. The ornamentation was found useful to distinguish among closely related species such as Galium aparine and G. spurium. A key for the identification of the investigated taxa based on pollen grains characters is provided. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Influence of comorbidity and cognitive status on instrumental activities of daily living in amnestic mild cognitive impairment: results from the ReGAl project
Authors: Mariani E. , Monastero R. , Ercolani S. , Rinaldi P. , Mangialasche F. , Costanzi E. , Vitale D. F. , Senin U. , Mecocci P. 
Published: December 2007

AbstractObjectivesTo investigate whether amnestic mild cognitive impairment (aMCI) is characterised by restriction in instrumental activities of daily living (IADL). Further, to examine the role of comorbidity and cognitive performance on IADL changes in aMCI subjects.MethodsThe study included 132 subjects with aMCI and 249 subjects with no cognitive impairment (NCI), consecutively enrolled as outpatients in a multicentric Italian clinical‐based study, the ReGAl Project. All subjects underwent a comprehensive evaluation including clinical examination, laboratory screening, neuroimaging and cognitive and behavioral assessments. Functional status was evaluated by the Lawton's Instrumental Activities of Daily Living (IADL) scale. Comorbidity was evaluated by the Cumulative Illness Rating Scale (CIRS). Cognitive evaluation included tests assessing episodic memory, language, attention/executive functioning and praxis, as well as the the Mini‐Mental State Examination (MMSE) as a measure of global cogniton.ResultsSubjects with aMCI had higher IADL changes than NCI. Among IADL items, aMCI subjects showed a significant impairment in shopping, taking drugs, and handling economy; however also NCI had minor IADL changes regarding cooking, washing and cleaning. IADL restriction in aMCI subjects was significantly associated with cognitive performance, mainly related to executive functioning, but not with comorbidity. On the contrary, in NCI sensory impairment accounts for slight IADL changes.ConclusionIn aMCI subjects a mild degree of cognitive deterioration has a stronger impact on IADL than somatic comorbidity. Current diagnostic criteria for MCI should include a mild impairment in IADL. Copyright © 2007 John Wiley & Sons, Ltd.
Medication errors in older people with mental health problems: a review
Authors: Maidment Ian D , Haw Camilla , Stubbs Jean , Fox Chris , Katona Cornelius , Franklin Bryony Dean 
Published: December 2007

AbstractObjectiveTo review and summarise published data on medication errors in older people with mental health problems.MethodsA systematic review was conducted to identify studies that investigated medication errors in older people with mental health problems. MEDLINE, EMBASE, PHARMLINE, COCHRANE COLLABORATION and PsycINFO were searched electronically. Any studies identified were scrutinized for further references. The title, abstract or full text was systematically reviewed for relevance.ResultsData were extracted from eight studies. In total, information about 728 errors (459 administration, 248 prescribing, 7 dispensing, 12 transcribing, 2 unclassified) was available. The dataset related almost exclusively to inpatients, frequently involved non‐psychotropics, and the majority of the errors were not serious.ConclusionsDue to methodology issues it was impossible to calculate overall error rates. Future research should concentrate on serious errors within community settings, and clarify potential risk factors. Copyright © 2007 John Wiley & Sons, Ltd.
Improvement in behavioural symptoms in patients with moderate to severe Alzheimer's disease by memantine: a pooled data analysis
Authors: Gauthier S. , Loft H. , Cummings J. 
Published: December 2007

AbstractIntroductionBehavioural disturbances are a common and distressing aspect of Alzheimer's disease (AD). This pooled analysis evaluated the specific benefits of memantine on behavioural disturbances in patients with moderate to severe AD.MethodsData were pooled from six 24/28‐week, randomised, placebo‐controlled, double‐blind studies. Of the 2,311 patients included in these studies, 1,826 patients with moderate to severe AD (MMSE <20) were included in this analysis, corresponding to the extended indication for memantine in Europe. In this subgroup, 959 patients received memantine 20 mg/day and 867 received placebo. Behavioural symptoms were rated using the Neuropsychiatric Inventory (NPI) total and single‐item scores at weeks 12 and 24/28.ResultsAt weeks 12 and 24/28, ITT analysis demonstrated that memantine treatment produced statistically significant benefits over placebo treatment in NPI total score (p = 0.001 and p = 0.008), and in NPI single items: delusions (p = 0.007 week 12, p = 0.001 week 24/28), hallucinations (p = 0.037 week 12), agitation/aggression (p = 0.001 week 12, p = 0.001 week 24/28), and irritability/lability (p = 0.005 week 24/28), LOCF population. Analysis of the patients without symptoms at baseline indicated reduced emergence of agitation/aggression (p = 0.002), delusions (p = 0.047), and disinhibition (p = 0.011), at week 12, and of agitation/aggression (p = 0.002), irritability/lability (p = 0.004), and night‐time behaviour (p = 0.050) at week 24/28 in those receiving memantine. OC analyses yielded similar results.ConclusionsThe data suggest that memantine is effective in treating and preventing the behavioural symptoms of moderate to severe AD. Specific persistent benefits were observed on the symptoms of delusions and agitation/aggression, which are known to be associated with rapid disease progression, increased caregiver burden, early institutionalisation, and increased costs of care. Copyright © 2007 John Wiley & Sons, Ltd.
High‐dose escitalopram in the treatment of binge‐eating disorder with obesity: a placebo‐controlled monotherapy trial
Authors: Guerdjikova Anna I. , McElroy Susan L. , Kotwal Renu , Welge Jeffrey A. , Nelson Erik , Lake Katie , Alessio David D' , Keck Paul E. , Hudson James I. 
Published: December 2007

AbstractObjectiveThe purpose of this study was to evaluate the efficacy and safety of high‐dose escitalopram in the treatment of binge‐eating disorder (BED) associated with obesity.MethodForty‐four outpatients with BED by DSM‐IV criteria and obesity were randomized to receive either escitalopram (N = 21) or placebo (N = 23) in a 12‐week, double‐blind, flexible dose (10–30 mg/day) study.ResultsIn the primary analysis, escitalopram (mean dose 26.5 mg/day) and placebo had similar rates of reduction of binge episodes, binge days and obsessive‐compulsive symptoms of BED. However, escitalopram was associated with statistically significant reductions in weight, body mass index (BMI), and global severity of illness scores. In a secondary analysis, escitalopram was associated with statistically significant reductions in frequency of binge episodes and binge days, weight, BMI and severity of illness, but not in obsessive‐compulsive symptoms of BED. No changes in metabolic variables, including measures of ghrelin and leptin, were observed. High‐dose escitalopram was well tolerated.ConclusionHigh‐dose escitalopram was not efficacious in reducing obsessive‐compulsive symptoms of BED, but was efficacious in reducing weight and global severity of illness. No definitive conclusions about its efficacy in reducing binge‐eating frequency could be drawn due to limitations related to statistical power. Copyright © 2007 John Wiley & Sons, Ltd.