bluuebunny/crossref_metadata_2025_split huggingface dataset:
Toxicity of spiromesifen to the developmental stages of Bemisia tabaci biotype B
Authors: Kontsedalov Svetlana , Gottlieb Yuval , Ishaaya Isaac , Nauen Ralf , Horowitz Rami , Ghanim Murad 
Published: September 2008

AbstractBACKGROUND: Spiromesifen is a novel insecticidal/acaricidal compound derived from spirocyclic tetronic acids that acts effectively against whiteflies and mites via inhibition of acetyl‐CoA‐carboxylase, a lipid metabolism enzyme. The effects of spiromesifen on the developmental stages of the whitefly Bemisia tabaci (Gennadius) were studied under laboratory conditions to generate baseline action thresholds for field evaluations of the compound.RESULTS: Adult B. tabaci mortality rate after spiromesifen treatment (5 mg L−1) was 40%. Treatment with 0.5 mg L−1 reduced fecundity per female by more than 80%, and fertility was almost nil. LC50 for eggs was 2.6 mg L−1, and for first instar 0.5 mg L−1. Scanning electron microscopy revealed that eggs laid by treated adult females had an abnormally perforated chorion, and females were unable to complete oviposition. Light and fluorescent microscopy showed significantly smaller eggs following treatment, and smaller, abnormally formed and improperly localized bacteriomes in eggs and nymphs. The number of ovarioles counted in females treated with 5 mg L−1 was significantly reduced. Spiromesifen showed no cross‐resistance with other commonly used insecticides from different chemical groups, and resistance monitoring in Israel showed no development of field resistance to this insecticide after 1 year of use.CONCLUSION: The strong effect on juvenile stages of B. tabaci with a unique mode of action and the absence of cross‐resistance with major commonly used insecticides from different chemical groups suggest the use of spiromesifen in pest and resistance management programmes. Copyright © 2008 Society of Chemical Industry
Efficient generation of Heisenberg Hamiltonian matrices for VB calculations of potential energy surfaces
Authors: Tokmachev A. M. , Robb M. A. 
Published: September 2008

AbstractThe spin‐Hamiltonian valence bond theory relies upon covalent configurations formed by singly occupied orbitals differing by their spin counterparts. This theory has been proven to be successful in studying potential energy surfaces of the ground and lowest excited states in organic molecules when used as a part of the hybrid molecular mechanics—valence bond method. The method allows one to consider systems with large active spaces formed by n electrons in n orbitals and relies upon a specially proposed graphical unitary group approach. At the same time, the restriction of the equality of the numbers of electrons and orbitals in the active space is too severe: it excludes from the consideration a lot of interesting applications. We can mention here carbocations and systems with heteroatoms. Moreover, the structure of the method makes it difficult to study charge‐transfer excited states because they are formed by ionic configurations. In the present work we tackle these problems by significant extension of the spin‐Hamiltonian approach. We consider (i) more general active space formed by n ± m electrons in n orbitals and (ii) states with the charge transfer. The main problem addressed is the generation of Hamiltonian matrices for these general cases. We propose a scheme combining operators of electron exchange and hopping, generating all nonzero matrix elements step‐by‐step. This scheme provides a very efficient way to generate the Hamiltonians, thus extending the applicability of spin‐Hamiltonian valence bond theory. © 2008 Wiley Periodicals, Inc. Int J Quantum Chem, 2009
A simple model for the band structure and D.C. conductivity of an infinite CO···HN chain perpendicular to the protein backbone
Authors: Bende Attila , Bogár Ferenc , Ladik János 
Published: September 2008

AbstractThe1 Hartree–Fock crystal orbital (CO) method in its linear combination of atomic orbitals form was applied to determine the band structure of histone proteins taking 0.041e charge transfer per nucleotide base from the PO groups of poly(guanilic acid) to the arginine, and lysine side chains in histones (see text). Assuming that there are infinite COs, perpendicular to the main chain, formed by the amide groups of one segment of the protein chain bound together by H‐bonds with the CO groups of another segment of the chain, we have calculated the band structure. From this, we have determined the mobility using the deformation potential approximation. Multiplying this with the mobile electron concentration due to the charge transfer between the PO groups of DNA and the positive side chains in histones, we have obtained for the direct current (D.C.) electron conductivity σfib = 1.07 × 10−9 Ω−1 cm for a single fiber and after division by the cross‐section of 9.10 × 10−16 cm2, σspec = 1.18 × 106 Ω−1 cm−1 for the specific conductivity. © 2008 Wiley Periodicals, Inc. Int J Quantum Chem, 2009
On the Hamiltonicity Gap and doubly stochastic matrices
Authors: Borkar Vivek S. , Ejov Vladimir , Filar Jerzy A. 
Published: September 2008

AbstractWe consider the Hamiltonian cycle problem embedded in singularly perturbed (controlled) Markov chains. We also consider a functional on the space of stationary policies of the process that consists of the (1,1)‐entry of the fundamental matrices of the Markov chains induced by these policies. We focus on the subset of these policies that induce doubly stochastic probability transition matrices which we refer to as the “doubly stochastic policies.” We show that when the perturbation parameter, ε, is sufficiently small, the minimum of this functional over the space of the doubly stochastic policies is attained at a Hamiltonian cycle, provided that the graph is Hamiltonian. We also show that when the graph is non‐Hamiltonian, the above minimum is strictly greater than that in a Hamiltonian case. We call the size of this difference the “Hamiltonicity Gap” and derive a conservative lower bound for this gap. Our results imply that the Hamiltonian cycle problem is equivalent to the problem of minimizing the variance of the first hitting time of the home node, over doubly stochastic policies. © 2008 Wiley Periodicals, Inc. Random Struct. Alg., 2009
A comparison of changes in secretory immunoglobulin A following a stress‐inducing and stress‐reducing task
Authors: Benham Grant , Nash Michael R. , Baldwin Debora R. 
Published: September 2008

AbstractResearch suggests that the immune system may be adversely affected by chronic stress. There is some evidence that relaxation‐based practices may effect an increase in immune functioning, but recent findings suggest that acute stress may lead to similar increases. Given this, we used a counterbalanced within‐subjects design to directly compare the effects of a stressful mental arithmetic task and a relaxation‐based task on secretory immunoglobulin A (S‐IgA). Thirty participants were seen in small groups of two or three where they were administered both a mental arithmetic (stress) task and a relaxing hypnosis task. Four‐minute timed saliva samples were obtained immediately following the two experimental tasks and following two baseline periods. Results demonstrated that, compared with baseline, S‐IgA concentration and secretion rate were significantly higher following both the relaxation‐based task and stress task. Additionally, our data showed that the increases were short‐lived, decreasing significantly within 8 min following the completion of each task. Our results indicate that both stress‐reducing and stress‐inducing tasks can increase S‐IgA levels, and these results are discussed with reference to the potential differential mechanisms and clinical significance of such changes. Copyright © 2008 John Wiley & Sons, Ltd.
Transport control of shear‐thinning fluids within corrugated microannulus
Authors: Chu Z.Kwang‐Hua , Qin Chen 
Published: September 2008

AbstractThe rheological characteristics and volume flow rates (up to the second order) of shear‐thinning fluids inside the transversely corrugated microannuli were obtained by using the verified fluid model and boundary perturbation method. Our results show that the temperature as well as wavy‐roughness could influence the transport of the shear‐thinning fluids significantly. Meanwhile, the phase shift between the outer and inner walls of microannuli could tune the transport of shear‐thinning fluids significantly when the wavy‐roughness (of the microannuli) is larger enough and the external forcing is small. Our results could be applied to the flow control in biofluidics and microfluidics.
ALE formulation of Reynolds fluid film equation
Authors: Schweizer B. 
Published: September 2008

AbstractThe pressure distribution in hydrodynamic journal bearings is usually calculated by the Reynolds fluid film equation, a linear elliptical partial differential equation. Applying appropriate boundary conditions, e.g., Reynolds boundary conditions, the governing boundary value problem becomes nonlinear. For solving this nonlinear boundary value problem, there exist several established methods. The paper at hand presents an alternative approach using an ALE (Arbitrary Lagrangian Eulerian) formulation.
The effect of the boundary slip on the stability of shear flow
Authors: He Qiaolin , Wang Xiao‐Ping 
Published: September 2008

AbstractWe study the linearized stability of shear flow satisfying Navier slip boundary conditions. The Orr‐Sommerfeld equation for the plane Poiseuille flow with Navier slip boundary conditions is solved numerically by the Chebyshev collocation method. Our numerical results show that slip at the boundary increases the critical Reynolds number Rc for instability. The dependence of the this critical Reynolds number on the slip length ls is found to be Rc(ls)‐ Rc(0) ≈ C ls2.
Thermoviscoplasticity at small strains
Authors: Bartels S. , Roubíček T. 
Published: September 2008

AbstractA viscoelastic solid in Kelvin‐Voigt rheology involving plasticity coupled with a heat‐transfer equation through a temperature‐dependent yield stress is investigated. No hardening is studied but the evolution of the plastic strain is considered to be rate‐dependent. A numerical scheme which is semi‐implicit in time and employs lowest order finite elements on weakly acute triangulations in space is devised and its convergence is proved by careful subsequent limit passage. Computational studies underline robustness and efficiency of the method and illustrate physical effects such as the softening of a material due to dissipated energy that causes a rise in temperature and a local decrease of the yield stress.
Prospective Outcomes of Selective Lymph Node Dissection for Papillary Thyroid Carcinoma Based on Preoperative Ultrasonography
Authors: Sugitani Iwao , Fujimoto Yoshihide , Yamada Keiko , Yamamoto Noriko 
Published: September 2008

AbstractBackgroundAlthough many patients with papillary thyroid carcinoma (PTC) display associated cervical lymph node metastases (LNM), the optimal extent of lymph node dissection (LND) remains a matter of debate. Since 1993, we have performed cervical LND based on the preoperative suspicion of LNM by ultrasonography (US). We prospectively analyzed the outcomes of our “selective” LND to determine when prophylactic lateral neck dissection is advisable.MethodsProspective analysis was conducted for 361 consecutive patients with PTC who received initial surgery between 1993 and 2001. Mean duration of follow‐up was 8.1 years. Dissection of the central compartment only was performed for patients with LNM in the central zone only and for patients with no LNM detected by US (Group A). Modified radical lateral neck dissection (MND; combined with central compartment dissection) was performed for patients diagnosed with lateral neck LNM (Group B).ResultsPathological LNM was found in 136 of 231 patients in Group A (59%). As for the accuracy of US diagnosis, positive predictive value was 82%. Nodal recurrences, occurring all in the lateral cervical region associated with one case of contralateral paratracheal region, was seen in 18 patients (8%) and 10‐year nodal disease‐free survival was 91%. Univariate analysis revealed true positive diagnosis by US, large primary tumor (≥4 cm), primary tumor located in the upper part of the thyroid lobe, presence of distant metastasis, extrathyroidal invasion of the primary tumor, and a poorly differentiated component of the primary tumor as significant risk factors for nodal recurrence. Among the risk factors that could be diagnosed preoperatively, distant metastasis (risk ratio, 46; p = 0.01) and large primary tumor (risk ratio, 3.6; p = 0.03) were the most important factors under multivariate analysis. Of the other 130 patients in Group B, only 3 patients had no pathological LNM (positive predictive value, 98%). Twenty‐six patients (20%) developed nodal recurrence, with a 10‐year nodal disease‐free survival of 76%. Age (50 years or older), large nodal metastasis (≥3 cm), extrathyroidal invasion, and higher serum thyroglobulin level (≥320 ng/ml) represented significant factors for nodal recurrence.ConclusionsWhen preoperative US shows no LNM or indicates only LNM in the central compartment, dissection of the central compartment alone offers a sufficient alternative to routine prophylactic MND. However, patients with PTC demonstrating large primary tumor and/or distant metastasis were high‐risk for recurrence in the lateral cervical compartment. We recommend prophylactic MND to reduce nodal recurrence for those patients.
A test of the latitudinal defense hypothesis: herbivory, tannins and total phenolics in four North American tree species
Authors: Adams Jonathan M. , Rehill Brian , Zhang Yangjian , Gower Jonathan 
Published: September 2008

AbstractIt is widely believed that insect herbivory is less intense at higher latitudes, due to winter mortality which would tend to keep insect herbivores from reaching density‐limitation of their populations. One prediction of this theory is that plants should tend to be better defended at lower latitudes. Here we investigated latitudinal trends in herbivory and tannins, in four species of common North American trees. Our comparisons spanned 15° of latitude in Acer rubrum, Fagus grandifolia, and Quercus alba, and 10° latitude in Liquidambar styraciflua. Sun leaves on forest edges were sampled, at phenologically equivalent times of year. Analysis revealed significant differences between populations, including those at similar latitudes, but no significant latitudinal trend in herbivory, condensed and hydrolyzable tannins, or total phenolics measured as Folin–Denis reactives in any of the four species. Our findings contradict the theory that low latitude plants are better defended, in that lower latitude populations of the four tree species showed no greater amounts of phenolics. The possible implications for community ecology are discussed.
Sesamin Increases Alpha‐Linolenic Acid Conversion to Docosahexaenoic Acid in Atlantic Salmon (Salmo salar L.) Hepatocytes: Role of Altered Gene Expression
Authors: Trattner Sofia , Ruyter B. , Østbye T. K. , Gjøen T. , Zlabek V. , Kamal‐Eldin A. , Pickova J. 
Published: September 2008

AbstractIn vitro cultivated Atlantic salmon (Salmo salar L.), hepatocytes were incubated without or with a mixture of sesamin and episesamin in order to test for possible effects on lipid metabolism. Sesamin/episesamin exposure (0.05 mM, final concentration) led to increased elongation and desaturation of 14C 18:3n‐3 to docosahexaenoic acid (14C 22:6n‐3, DHA, P < 0.01) and down regulated gene expression of Δ6 and Δ5 desaturases compared to control treatment. Sesamin/episesamin further increased the hepatocytes capacity for fatty acid β‐oxidation of 14C 18:3n‐3 (P < 0.01) to the 14C acid soluble products, acetate, malate and oxaloacetate, in agreement with an increased gene expression of carnitine palmitoyltransferase I. Also the gene expression of cluster of differentiation 36 was upregulated and the expression of scavenger receptor type B, peroxisome proliferator‐activated receptors α and γ were downregulated. The amount of triacylglycerols secreted by the cells tended to be lower in the sesamin/episesamin incubated hepatocytes than the control cells. This study shows that sesamin has favourable effects on lipid metabolism leading to increased level of DHA, which may be of interest for aquaculture use.
Advanced imaging of the cervical spine and spinal cord in 22q11.2 deletion syndrome: Age-matched, double-cohort, controlled study
Authors: Ricchetti Eric T. , Hosalkar Harish S. , Gholve Purushottam A. , Cameron Danielle B. , Drummond Denis S. 
Published: September 2008

Purpose The 22q11.2 deletion syndrome is a common genetic syndrome with a wide spectrum of abnormalities. We have previously described multiple anomalies of the upper cervical spine in this disorder. The objective of this study was to use advanced imaging to further define the morphology of the cervical spine and spinal cord in the 22q11.2 deletion syndrome, with a comparison to age-matched controls. Methods A total of 32 patients with a 22q11.2 deletion underwent advanced imaging (computed tomography/magnetic resonance imaging; CT/MRI) of the cervical spine. In 27 patients, space available for the cord (SAC); the sagittal diameter of the vertebral body, spinal canal, cerebrospinal fluid (CSF), and spinal cord; and the cross sectional area of the spinal canal, CSF, and spinal cord were measured at each cervical level and compared to 29 age-matched controls. Statistical analysis was performed and potential implications were hypothesized. Results In 22q11.2 patients, advanced imaging identified 40 pathologies not evident on plain radiographs with potential mechanical and/or neurological implications. These patients also had significantly smaller values ( P ≤ 0.05) of the following parameters at one or more cervical levels, relative to age-matched controls: width of the vertebral body, spinal canal, CSF, and spinal cord; area of the spinal canal, CSF, and spinal cord. Neurologic symptoms were observed in 4/32 patients, with one patient requiring surgical intervention. Conclusions Advanced imaging of the cervical spine can detect findings not evident on plain radiographs in the 22q11.2 deletion syndrome. CT and/or MRI may be indicated when there is a high index of suspicion for clinical instability or neurologic compromise in order to rule out dynamic encroachment or impending neurologic sequelae. Spinal canal and spinal cord dimensions are reduced in these patients relative to controls with currently unknown clinical significance.
Existence of minimizers of free autonomous variational problems via solvability of constrained ones
Authors: Cupini Giovanni , Guidorzi Marcello , Marcelli Cristina 
Published: September 2008

We consider the following autonomous variational problem

\text{minimize }\left\{\:\int \limits_{a}^{b}f\left(v(x),v^{′}(x)\right)\:\mathrm{d}x:\:v∊W^{1,1}(a,b),\:v(a) = \alpha ,\:v(b) = \beta \right\}

where the Lagrangian

f

is assumed to be continuous, but not necessarily coercive, nor convex. We show that the existence of the minimum is linked to the solvability of certain constrained variational problems. This allows us to derive existence theorems covering a wide class of nonconvex noncoercive problems.

Résumé
On considère la classe des problèmes variationels autonomes ci-dessous :

\text{minimiser }\left\{\:\int \limits_{a}^{b}f\left(v(x),v^{′}(x)\right)\:\mathrm{d}x:\:v∊W^{1,1}(a,b),\:v(a) = \alpha ,\:v(b) = \beta \right\}

où le lagrangien

f

est une fonction continue sans hypothèse de coercivité ou de convexité. On démontre que l'existence de solutions pour ces problèmes est liée à l'existence de solutions de certains problèmes variationels sous contraintes. Ce résultat permet d'obtenir des théorèmes d'existence pour une classe étendue de problèmes variationels ni coercifs ni convexes.
Perioperative ketamine does not prevent chronic pain after thoracotomy
Authors: Dualé Christian , Sibaud Fabrice , Guastella Virginie , Vallet Laurent , Gimbert Yves‐Alain , Taheri Hammou , Filaire Marc , Schoeffler Pierre , Dubray Claude 
Published: September 2008

ABSTRACTThoracotomy is often responsible for chronic pain, possibly of neuropathic origin. To confirm preclinical studies, the preventive effects of perioperative ketamine were tested in a randomized, double‐blind, placebo‐controlled clinical trial on persistent neuropathic pain after thoracotomy. Eighty‐six patients scheduled for thoracotomy under standardised general anaesthesia were randomised to receive either ketamine (1mgkg−1 at the induction, 1mgkg−1h−1 during surgery, then 1mgkg−1 during 24h; n=42) or normal saline (n=44). Postoperative analgesia included a single dose of intrapleural ropivacaine, intravenous paracetamol and nefopam, and patient‐controlled intravenous morphine. Vital parameters and analgesia were recorded during the 48 first postoperative hours. Seventy‐three patients were followed up. The patient's chest was examined 1–2 weeks, 6 weeks and 4 months after surgery. At the last two observations, spontaneous pain score over a one‐week period (visual analogue scale), neuropathic pain score (NPSI), and intake of analgesics, were assessed. No drug affecting neuropathic pain (except opiates) was given during the follow‐up. Two patients in each group were lost to follow‐up after the 6 week visit. Ketamine improved immediate postoperative pain, but the groups were similar in terms of neuropathic pain and intake of analgesics, 6 weeks (NPSI score: ketamine: 1.25 [0–4.125]; placebo: 1 [0–4]) and 4 months after surgery. Thus, ketamine given in 24‐h infusion failed to prevent chronic neuropathic pain after thoracotomy. Other perioperative preventive long‐lasting treatments or techniques could be tested in this context.
Prospects for the classification of mental disorders of children and adolescents
Authors: Schmidt M.H. , Sinzig J. 
Published: September 2008

AbstractSuggestions for classification of mental disorders of children and adolescents in DSM-V and ICD-11 have been made, which differ strongly from the current descriptive approach of dimensional classification.These suggestions even comprise a dichotomized system for health care as well as for scientific purposes.Nevertheless it is obvious that we are far behind an “etiological” classification, so that trade-offs have necessarily to be made in DSM-V and ICD-11.Appropriate proposals concern the strict separation of disorders that are typical for children and adolescents as well as for adults.Furthermore a differentiation of diagnosis for infants, toddlers and preschool children is required in both classification systems. As far as it is relevant for treatment, combined diagnosis in DSM-V and subthreshold diagnosis as well as coding-possibilities for findings in molecular biology should be permitted.As personality disorders should only be diagnosed after the age of 16, it is recommended to dimensionally classify personality traits that are pathognomonic for specific symptom patterns and of prognostic relevance.DSM-V and ICD-11 should allow age-specific information on axis-IV. The article discusses the general question of how relational disorders respectively disturbances should be classified and include furthermore special recommendations concerning ICD and DSM categories.