bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis of cyclooctapeptides: constraints analogues of the peptidic neurotoxin, ω‐agatoxine IVB—an experimental point of view
Authors: Minta Ewelina , Kafarski Pawel , Martinez Jean , Rolland Valérie 
Published: September 2007

Abstractω‐AGA IVB is an important lead structure when considering the design of effectors of glutamate release inducting P/Q‐type calcium channels. The best route to achieve the analogues possessing the three‐dimensional arrangement corresponding to the native binding loop was the introduction of constraint by ring formation via side chain to side chain lactamization for suitably protected Lys and Glu residues. Since tryptophane residue located at position 14 of this neuropeptide has been suggested as essential for binding, analogues in which this amino acid was replaced by aza‐tryptophane and alanine were synthesized. The synthesis was carried out on various acid‐labile resins (BARLOS chlorotrityl, Rink amide, PEG‐based or Wang resins), by Fmoc strategy. In this paper, we describe optimization of the peptide cyclization with various protecting groups, and on resin or in solution cyclization experimental parameters. Copyright © 2007 European Peptide Society and John Wiley & Sons, Ltd.
GISAXS study of the alignment of oriented carbon nanotubes grown on plain SiO2/Si(100) substrates by a catalytically enhanced CVD process
Authors: Mane Mane J. , Cojocaru C. S. , Barbier A. , Deville J. P. , Thiodjio Sendja B. , Le Normand F. 
Published: September 2007

AbstractWe report a quantitative Grazing Incidence Small Angle X‐Ray Scattering (GISAXS) study of the alignment of mutually oriented carbon nanotubes (CNTs) grown by a catalytically‐activated, a plasma direct current and hot filaments‐assisted (DC HF CCVD) process. Metallic catalytic (Co) islands were dispersed on plain SiO2 (5 nm thickness)/Si(100) substrates prior the growth of CNTs which can be considered as highly anisotropic 1D nanostructures. The GISAXS pattern analysis in the framework of the Distorted‐Wave Born Approximation (DWBA) has been expanded to multilayered non‐correlated surface science systems (non‐correlated carbon nanotubes) and is based on the determination of carbon nanotubes density, characteristic lengths, atomic Co dispersion throughout the CNTs and roughnesses of the uncorrelated particles. Even dominated by envelope features of disordered objects, they provide noticeable information about CNTs films: both structural (orientation, size and length distribution) and correlation (density, mutual alignment) information. The results stand in rather good agreement with the Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM) observations. Moreover, the GISAXS patterns could only be satisfactorily reproduced by adding a mixed C–Co contribution between the pure carbon and the metallic cobalt let on top of the CNT, inferring that cobalt continuously fills the nanotube in the course of the growth and that the CNTs experience a large tendency toward mutual alignment. The effect of variable X‐ray incidence angles has been investigated. With a weak addition of ammonia (from 1% to 3% of the gas mixture) the density has been found to decrease by more than one order of magnitude. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Three‐Dimensional Holographic Vector of Atomic Interaction Field Applied in QSAR of Anti‐HIV HEPT Analogues
Authors: Tong Jianbo , Liu Shuling 
Published: September 2007

AbstractA newly developed Three‐Dimensional Holographic Vector of Atomic Interaction Field (3D‐HoVAIF) was used to describe the chemical structures of 35 anti‐human immunodeficiency virus drugs as 1‐[(2‐Hydroxyethoxy)‐Methyl]‐6‐(Phenylthio)Thymine (HEPT). Here two Quantitative Structure–Activity Relationship (QSAR) models were built by both Partial Least Square (PLS) regression and Support Vector Machine (SVM) regression. Both estimation stability and prediction ability of these models were strictly analyzed by both internal and external validations. The correlation coefficient (R2) of established PLS and SVM models, Leave‐One‐Out (LOO) Cross‐Validation (CV), prediction values versus experimental ones of external samples were Rcum2=0.922, QCV2=0.656, Qext2=0.624 (PLS) and Rcum2=0.821, QCV2=0.797, Qext2=0.771 (SVM), respectively. The results of SVM were found to be better than those of PLS and Multiple Linear Regression (MLR) as previously reported by Garg et al. (Chem. Rev. 1999, 99, 3525–3601), which had both favorable estimation stability and good prediction capabilities. Satisfactory results showed that 3D‐HoVAIF could preferably express information related to biological activity of HEPT.
Robust discontinuous exponential regulation of dynamic nonholonomic wheeled mobile robots with parameter uncertainties
Authors: Ma B. L. , Tso S. K. 
Published: September 2007

AbstractFor regulating a dynamic nonholonomic WMR (wheeled mobile robot) with parameter uncertainties, we derive a simple robust discontinuous control law, yielding a global exponential convergence of position and orientation to the desired set point despite parameter uncertainties. The controller design relies on separating the error dynamics into two subsystems, followed by robust feedback control laws to stabilize the subsystems. The effectiveness of the proposed control laws is verified by simulation. Copyright © 2007 John Wiley & Sons, Ltd.
Synthesis of Magnetic Microspheres with Controllable Structure via Polymerization‐Triggered Self‐Positioning of Nanocrystals
Authors: Xia Ao , Hu Jianhua , Wang Changchun , Jiang Donglin 
Published: September 2007

AbstractA facile and novel method for the synthesis of magnetite–polymer hybrid microspheres with controllable structure is reported. On the basis of the interactions between polymers and magnetic nanocrytals, which are coated with a primary oleic acid layer, a variety of magnetic microspheres with well‐tailored structure are fabricated by carefully modulating polymerization and selecting components of composite microspheres; the evolvement of hierarchical structure, and the magnetic properties of microspheres were systematically studied. Importantly, the mechanism of polymerization‐triggered self‐positioningof magnetic nanocrystals is investigated.
Neurophysiological actions of methylphenidate in the primary somatosensory cortex
Authors: Drouin Candice , Wang Dorothy , Waterhouse Barry D. 
Published: September 2007

AbstractAs a catecholamine reuptake blocker, methylphenidate (MPH) enhances noradrenergic transmission and is likely to influence norepinephrine actions in sensory systems. To characterize neurophysiological actions of MPH in the primary somatosensory (SI) cortex, we recorded basal and whisker deflection‐evoked discharge of infragranular sensory cortical neurons, before and after intraperitoneal administrations of saline and MPH (5 mg/kg) in halothane‐anesthetized rats. MPH had two types of actions on sensory‐evoked neuronal responses in the SI cortex, depending on the initial amplitude of the sensory response. When the whisker deflection induced a small excitatory response under control conditions, MPH significantly increased the amplitude of the response by ∼40%. When the whisker stimulation induced a large excitatory response under control conditions, MPH did not significantly alter the amplitude of the response, but significantly decreased the duration and the peak latency of the response, so that the response was more focused. These neurophysiological actions of MPH may underlie some of the beneficial effects of the drug on sensory processing and attention.Synapse 61:985–990, 2007. © 2007 Wiley‐Liss, Inc.
Diversity combining with up‐link power control
Authors: Nam Sung Sik , Alouini Mohamed‐Slim , Qaraqe Khalid A. 
Published: September 2007

AbstractWe introduce in this paper a new adaptive power‐controlled diversity combining scheme that reduces the average transmitted power of the mobile units (MUs) while meeting a certain minimum required quality of service. The key idea is (i) to collect and combine all the available diversity paths at the base station (BS) and then (ii) to request the MU to increase or decrease its transmitted power just to track the required target signal‐to‐noise ratio (SNR). Four power control variants accounting for practical implementation constraints including discrete power levels and transmitter gain saturation are proposed and studied. Some selected numerical results show that the proposed scheme offers considerable savings in the transmitted power levels over a wide SNR range but amplifier saturation leads to a violation of the target BER requirement in the low average SNR range. Additional numerical examples show that the power control variants that take into account practical implementation constraints conserve the main features of the ideal continuous power algorithm. Copyright © 2007 John Wiley & Sons, Ltd.
QuESt: a QoS‐based energy efficient sensor routing protocol
Authors: Saxena Navrati , Roy Abhishek , Shin Jitae 
Published: September 2007

AbstractRapid penetration of smart wireless devices and enormous growth of wireless communication technologies has already set the stage for deployment of wireless sensor networks (WSNs). While these small sensor nodes are often considered as the future of wireless communications, they also suffer from energy constraints. On the other hand, with increasing demand for real‐time services in next generation wireless networks, quality‐of‐service (QoS)‐based routing has emerged as an interesting research topic. Naturally offering some QoS‐guarantee in sensor networks raises significant challenges. The network needs to cope up with battery‐constraints, while providing precise QoS (end‐to‐end delay and bandwidth requirement) guarantee. More precisely, designing such QoS‐protocols, optimizing multiple objectives, is computationally intractable. Based on the multi‐objective genetic algorithm (MOGA), in this paper we propose a QoS‐based energy‐efficient sensor routing (QuESt) protocol that determines application‐specific, near‐optimal sensory‐routes demand, by optimizing multiple QoS parameters, (end‐to‐end delay and bandwidth requirements) and energy consumption. Simulation results demonstrate that the proposed protocol is capable of discovering a set of QoS‐based, near‐optimal routes, even with imprecise network information. Copyright © 2007 John Wiley & Sons, Ltd.
On the performance of BICM with mapping diversity in hybrid ARQ
Authors: Szczecinski Leszek , Diop Fatou‐Kiné , Benjillali Mustapha 
Published: September 2007

AbstractHybrid ARQ with packet combining for high‐order modulations (such as 16‐QAM) may be significantly enhanced if the bits‐to‐symbols mappings are appropriately changed throughout the transmissions. In this paper, we analyze the relationship between such mapping diversity and channel coding. We calculate the capacity of the popular bit‐interleaved‐coded modulation (BICM) to draw qualitative and approximate quantitative conclusions that are valid for strong codes approaching the capacity limits. We conclude that the choice/design of the appropriate mapping depends on the targeted spectral efficiency and we demonstrate that certain forms of mapping diversity may be counterproductive. We also show that iterative demapping may be successfully applied to significantly reduce (by more than 1 dB) the gap between the BICM and coded modulations (CM) capacities. The analysis is illustrated with results obtained when the mapping diversity is combined with practical turbo codes. Copyright © 2007 John Wiley & Sons, Ltd.
Application and methodology of in vivo K x‐ray fluorescence of Pb in bone (impact of KXRF data in the epidemiology of lead toxicity, and consistency of the data generated by updated systems)
Authors: Nie Huiling , Hu Howard , Chettle David R. 
Published: September 2007

AbstractK x‐ray fluorescence (KXRF) technology has been used to make in vivo measurements of lead in bone for more than three decades. The data obtained are beneficial to research on lead toxicity as well as, in certain circumstances, the practice of occupational and environmental medicine. This paper reviews the impact of KXRF data on epidemiologic research involving lead toxicity and demonstrates that bone lead is and will continue to be a valuable biomarker in addressing long‐term health effects related to cumulative exposure. The KXRF system has been improved and upgraded several times ever since it was first used. The consistency of the data obtained from these KXRF systems has been investigated in many studies. This paper provides an overview of the factors that will affect the data generated by the KXRF systems. A calibration problem encountered in one of the major KXRF laboratories is described, and the approach taken to solve the problem is discussed. Despite all the theoretical considerations, there are still some important practical challenges to the intercalibration of KXRF instruments both within the laboratory, and between laboratories. Copyright © 2007 John Wiley & Sons, Ltd.
Hydrolysis of Epoxidized Soybean Oil in the Presence of Phosphoric Acid
Authors: Guo Yinzhong , Hardesty Jon H. , Mannari Vijay M. , Massingill John L. 
Published: September 2007

AbstractRing‐opening hydrolysis of epoxidized soybean oil in the presence of phosphoric acid was studied under varying experimental conditions. The influence of type and amount of solvents, phosphoric acid content and water content on the rate of ring‐opening reactions and the characteristics of the derived products were studied. The soy‐polyols prepared were characterized by determination of hydroxyl content, viscosity measurements, determination of average molecular weight and polydispersity index (GPC). The structural confirmation was done by FT‐IR and 1H‐NMR spectroscopy. The study shows that under the reaction conditions employed, a substantial degree of oligomerization due to oxirane‐oxirane, and/or oxirane‐hydroxyl reaction takes place. It is possible to synthesize soy‐polyols having varying hydroxyl content and phosphate‐ester functionality by controlling the type and amount of polar solvent and phosphoric acid content.
Prevalence, severity, and chronicity of pain and general health‐related quality of life in patients with localized prostate cancer
Authors: Gerbershagen Hans J. , Özgür Enver , Straub Karin , Dagtekin Oguzhan , Gerbershagen Kathrin , Petzke Frank , Heidenreich Axel , Lehmann Klaus A. , Sabatowski Rainer 
Published: September 2007

AbstractAims: To analyze the prevalence and the severity spectrum of pain and its relationships to health‐related quality of life and the bio‐psycho‐social consequences of pain among patients scheduled for radical prostatectomy.Methods: Urological inpatients completed an epidemiological pain questionnaire extensively exploring pre‐operative acute and chronic pains in 21 body regions. The severity of pain was determined using von Korff's Pain Grading (CPGQ). Pain chronicity was estimated employing the Mainz Pain Staging System (MPSS). Anxiety and depressive symptoms were identified with the HADS and the Habitual Well‐Being Questionnaire (FW‐7). Health‐related quality of life was measured using the SF‐12. Comorbidities and comorbidity‐related interferences with daily activities were ascertained with the Weighted Illness Checklist (WICL).Results: Eighty of 115 patients (69.6%) reported about pain during the last 3 months pre‐operatively. 28.7% of the pain patients had pain related to urological disease. Severe dysfunctional pain was identified by pain Grades 3 and 4 of the CPGQ in 20% and 13.8%, respectively. Advanced pain chronicity characterized by pain Stages II and III of the MPSS was present in 38.8% and 11.3%. Patients with localized prostate cancer without pain complaints had significantly better health‐related quality of life and habitual well‐being and lower anxiety and depression scores and fewer comorbidities. Patients with cancer‐related and non‐cancer pain did not differ in pain chronicity, pain severity, pain intensities, anxiety, comorbidities and physical health (SF12‐PCS).Conclusions: The high prevalence of severe and chronic pain in cancer patients before scheduled radical prostatectomy – combined with considerable disability effects and markedly reduced quality of life necessitate a short routine screening‐analysis of the severity spectrum of pain and psychopathology. Patient self‐rated pain chronicity staging and psychological distress analysis will allow a disorder severity‐guided treatment and the prevention of suffering and additional new chronic post‐surgical pain.
The responses of serum transferrin receptors to iron supplements in subjects with iron-deficiency erythropoiesis and iron-deficiency anaemia
Authors: Lin Xiao-Ming , Tian Wei , Ma Le , Long Zhu , Zhang Juan , Shen Xiao-Yi , Zhang Xiao-Peng 
Published: September 2007

We aimed to study the response of serum transferrin receptors (sTfR) to Fe supplementation in women of childbearing age with Fe-deficiency erythropoiesis (IDE) and Fe-deficiency anaemia (IDA). Primary screening was performed in 942 women ranging in age from 18 to 45 years. After Fe-related biochemical indices such as serum ferritin, Zn protoporphyrin and Hb were determined, the subjects were divided into four groups: normal, Fe store depletion, IDE and IDA. A total of 131 women were randomly selected from the normal, IDE and IDA groups. Subsequently, seventy-six women with IDE and IDA were given various doses of Fe (14 mg/d for IDE; 28 mg/d for IDA) with ferrousl-threonate capsules for twelve consecutive weeks. After receiving Fe supplements, the levels of Fe and sTfR were determined at weeks 0, 3, 6, 9 and 12.The levels of sTfR in women of childbearing age with IDE and IDA were significantly higher than those in the normal group. After receiving Fe supplements, the levels of sTfR were significantly decreased in women of childbearing age with IDE and IDA, while the levels of serum ferritin were significantly increased. In conclusion, STfR can be used as a reliable indicator for assessing the efficacy of Fe supplements.
Effect of the LoBAG30 diet on blood glucose control in people with type 2 diabetes
Authors: Nuttall Frank Q. , Schweim Kelly , Hoover Heidi , Gannon Mary C. 
Published: September 2007

In subjects with untreated type 2 diabetes, we previously determined that a weight-maintenance, non-ketogenic diet containing 30 % protein, 50 % fat and 20 % carbohydrate (30:50:20) decreased the percentage total glycohaemoglobin (%tGHb) by 2·2 % glycohaemoglobin over 5 weeks compared to a diet recommended for the American public (protein–fat–carbohydrate 15:30:55). Both the fasting and postprandial glucose were decreased. The objective of the present study was to determine if increasing the carbohydrate content from 20 to 30 % at the expense of fat would still provide a similar effect on %tGHb, fasting and postprandial glucose concentration. Eight men with untreated type 2 diabetes were studied over a 5-week period. Results at the beginning (standard diet) and end of the 5-week study were analysed. Body weight was stable. Fasting glucose concentration decreased by 40 %; 24 h glucose area response decreased by 45 %. Insulin did not change. Mean %tGHb decreased by 1·7 (from 10·8 to 9·1 %), and was still decreasing linearly at 5 weeks. In conclusion, a high-protein, 30 % carbohydrate diet could be a patient-empowering method of improving the hyperglycaemia of type 2 diabetes without pharmacologic intervention. Long-term effects and general applicability of this diet remain to be determined.
The ontogeny and systematics of the otarionine trilobiteOtarionellafrom the Devonian of the Montagne Noire, France and the Maider, Morocco
Authors: LEROSEY-AUBRIL RUDY , FEIST RAIMUND , CHATTERTON BRIAN D. E. 
Published: September 2007

AbstractA new otarionine trilobiteOtarionella rastrumsp. nov., from the late Emsian Mont Peyroux Formation (Montagne Noire, France), is described. Silicified remains, recovered from the underlying Bissounel Formation (early to late Emsian), are also attributed to this new species. These isolated silicified sclerites represent metaprotaspid to young holaspid growth stages, which enables the almost complete ontogeny of an otarionine trilobite with a spinose adult morphology to be described for the first time. Comparison with associated larval and juvenile growth stages ofCyphaspisreveal that the pattern of juvenile cranidial spine distribution inOtarionella rastrumsp. nov. differs from all patterns described so far in the Otarioninae, in particular that characterizing the tribe Otarionini. A second species,Otarionella lkomaliisp. nov., known only from a complete articulated specimen discovered in the early Eifelian of southern Morocco, is also described. Like the middle EifelianOtarionella chamaeleo(Basse, 1997), this new species has only ten thoracic segments, with the fourth and the sixth segments each bearing a long axial spine. In the light of the new elements provided by the ontogenetic sequence ofO. rastrumsp. nov. and the adult specimens of this species andO. lkomaliisp. nov., the putative synonymy ofOtarionellaandOtarionis rejected and a restricted concept of the genusOtarionellais defined.
RAPID FERTILITY DECLINE IN IRAN: ANALYSIS OF INTERMEDIATE VARIABLES
Authors: ERFANI AMIR , MCQUILLAN KEVIN 
Published: September 2007

SummaryThe remarkable decline in fertility in Iran, which saw the total fertility rate fall from 7 children per woman in 1986 to 2 in 2000, has received only limited analysis in the demographic literature. Using the 2000 Iran Demographic and Health Survey and Bongaarts’ age-specific fertility model, this paper examines the role of the major proximate determinants of fertility in bringing about the rapid decrease in fertility in Iran. The analysis indicates that contraception had the largest effect on fertility, accounting for 61% of the reduction in fertility from its theoretical maximum. The fertility-inhibiting effect of marriage patterns accounted for an additional 31% reduction, and was most important among the young. Further analysis of contraceptive behaviour suggests that the current period fertility rate of 2·0 children per woman is an outcome of a synchronization of delaying and spacing of births among younger women with stopping of childbearing among women in the middle and late reproductive ages. The policy implications of the results are discussed.
Vertigo, dizziness and imbalance in the elderly
Authors: Üneri A , Polat S 
Published: September 2007

AbstractObjective:The aim of this retrospective analysis was to evaluate the diagnosis of vertigo, dizziness and imbalance in elderly patients in two tertiary neurotology clinics.Design and setting:Six hundred and seventy-seven patients aged over 65 years were assessed by the same senior author, and 601 patients were enrolled in the study.Results:The most frequent diagnoses were benign paroxysmal positional vertigo (42.43 per cent), idiopathic vestibulopathy (20.29 per cent), migraine vestibulopathy (13.15 per cent), Ménière's disease (12.47 per cent) and acute vestibular attack (6.49 per cent).Conclusion and significance:This retrospective study showed that 93.5 per cent of the elderly patients studied had been diagnosed with peripheral vertigo. The majority of patients had been classified as having benign paroxysmal positional vertigo, idiopathic vestibulopathy or migraine vestibulopathy.