bluuebunny/crossref_metadata_2025_split huggingface dataset:
Simultaneous Atlantic–Pacific blocking and the Northern Annular Mode
Authors: Woollings Tim , Hoskins Brian 
Published: October 2008

AbstractA synoptic situation termed ‘high‐latitude blocking’ (HLB) is shown to occur frequently in both the Atlantic and Pacific sectors, and to result in flow anomalies very similar to those associated with the negative phase of the Northern Annular Mode (NAM) in the respective sector. There is a weak but significant link between the occurrence of HLB in the two sectors, with Atlantic HLB tending to lead Pacific HLB by 1–3 days. This link arises from rare events in which both sectors are almost simultaneously affected by a large‐scale wave‐breaking event which distorts the polar trough over Northern Canada. In several cases the tropospheric wave‐breaking occurs in tandem with a large‐scale disturbance of the stratospheric polar vortex.There is, therefore, a physical link between the Atlantic and Pacific sectors, but analysis suggests that this does not contribute to determining the pattern of the NAM, as conventionally defined from monthly mean data. However, an alternative version of the NAM, derived directly from daily data, does appear to reflect this physical link. These conflicting results highlight the sensitivity of the NAM to the period over which data are averaged. Copyright © 2008 Royal Meteorological Society
Small‐scale precipitation variability in the Alps: Climatology in comparison with semi‐idealized numerical simulations
Authors: Zängl G. , Aulehner D. , Wastl C. , Pfeiffer A. 
Published: October 2008

AbstractThis study examines small‐scale precipitation patterns in a north‐Alpine region, and their dependence on the freezing level and on the crest‐level (700 hPa) wind direction and speed. On the one hand, measurements from a uniquely dense operational rain‐gauge network are analyzed for a period of 15 years (1991‐‐2005). Information on the ambient atmospheric fields was extracted from climate‐mode MM5 simulations driven with ECMWF (re‐analysis data. On the other hand, high‐resolution semi‐idealized MM5 simulations have been conducted, combining realistic topography with idealized atmospheric fields. The atmospheric flow parameters have been chosen to be representative of those used to classify the observational data, focusing on atmospheric conditions conducive to stratiform, orographically enhanced precipitation in the region under consideration.The results of the data analysis indicate a pronounced tendency for local precipitation maxima in the lee of individual mountain ridges, whereas the variability between stations in the centre of wider valleys and stations on the windward foot of individual ridges is comparatively small. This points towards a strong contribution of local precipitation enhancement due to the seeder‐‐feeder mechanism, combined with downstream advection of the precipitating hydrometeors by the ambient winds. The data analysis also reveals that strong winds and high temperatures tend to shift the precipitation field towards the interior of the Alps, whereas low temperatures and weak winds favour precipitation maxima near the northern edge of the Alps. The semi‐idealized simulations are consistent with these findings, but their quantitative agreement with the observed precipitation patterns depends on the ambient flow conditions. The closest agreement is found for atmospheric conditions conducive to strong orographic lifting, for which our present idealized flow fields were designed. Lower skill is obtained for conditions not dominated by orographic lifting, which implies that future work should include a generalization of the idealized flow fields. Nevertheless, precipitation patterns generated with semi‐idealized simulations seem to be very promising to support the spatial interpolation of point measurements (such as are needed for precipitation climatologies), which currently is usually based on statistical methods rather than physically motivated structures. Copyright © 2008 Royal Meteorological Society
Hosoya polynomials of TUC4C8(R) nanotubes
Authors: Chen Jianfu , Xu Shoujun , Zhang Heping 
Published: October 2008

AbstractFor a connected graph G, the Hosoya polynomial of G is defined as H(G, x) = ∑{u,v}⊆V(G)xd(u, v), where V(G) is the set of all vertices of G and d(u,v) is the distance between vertices u and v. In this article, we obtain analytical expressions for Hosoya polynomials of TUC4C8(R) nanotubes. Furthermore, the Wiener index and the hyper‐Wiener index can be calculated. © 2008 Wiley Periodicals, Inc. Int J Quantum Chem, 2009
The dual sense of the term “element,” attempts to derive the Madelung rule, and the optimal form of the periodic table, if any
Authors: Scerri Eric R. 
Published: October 2008

AbstractThis article concerns various foundational aspects of the periodic system of the elements. These issues include the dual nature of the concept of an “element” to include element as a “basic substance” and as a “simple substance.” We will discuss the question of whether there is an optimal form of the periodic table, including whether the left‐step table fulfils this role. We will also discuss the derivation or explanation of the [n + ℓ, n] or Madelung rule for electron‐shell filling and whether indeed it is important to attempt to derive this rule from first principles. In particular, we examine the views of two chemists, Henry Bent and Eugen Schwarz, who have independently addressed many of these issues. © 2008 Wiley Periodicals, Inc. Int J Quantum Chem, 2009
Sensitive analysis of anti‐HIV drugs, efavirenz, lopinavir and ritonavir, in human hair by liquid chromatography coupled with tandem mass spectrometry
Authors: Huang Yong , Gandhi Monica , Greenblatt Ruth M. , Gee Winnie , Lin Emil T. , Messenkoff Nicholas 
Published: October 2008

AbstractA highly sensitive and selective method using liquid chromatography coupled with tandem mass spectrometry (LC/MS/MS) was developed and validated for the measurement of three antiretroviral agents, efavirenz, lopinavir and ritonavir, in human hair. Hair samples from adherent HIV‐infected patients on antiretroviral therapies were cut into about 1 mm length segments and drugs were extracted by first shaking the samples with methanol in a 37°C water bath overnight (>14 h), followed by methyl tert‐butyl ether/ethyl acetate (1:1) extraction under weak alkaline conditions. The extracted lopinavir and ritonavir were separated by reversed‐phase chromatography and detected by tandem mass spectrometry in electrospray positive ionization mode with multiple reaction monitoring (MRM), while efavirenz was monitored in negative ionization MRM mode. This method was validated from 0.01 to 4.0 ng/mg hair for ritonavir and 0.05–20 ng/mg hair for lopinavir and efavirenz by using 2 mg of a human hair sample. The interday and intraday assay precision (coefficients of variation, CV) for spiked quality control (QC) samples at low, medium and high concentrations were within 15% and accuracy ranged from 89% to 110%. Assay reproducibility was also demonstrated by analysis of incurred hair QC samples (CV <14%). No significant matrix ionization suppression was observed. This developed method allowed for the monitoring of these target medications in the hair samples of HIV‐infected women on antiretroviral therapy in an observational study using small amounts of hair. Copyright © 2008 John Wiley & Sons, Ltd.
Making classroom assessment more accountable to scientific reasoning: A case for attending to mechanistic thinking
Authors: Russ Rosemary S. , Coffey Janet E. , Hammer David , Hutchison Paul 
Published: October 2008

AbstractWhen teachers or students assess the quality of ideas in science classes, they do so mostly based ontextbook correctness; ideas are good to the extent they align with or lead to the content as presented in the textbook or curriculum. Such appeals to authority are at odds with the values and practices within the disciplines of science. There has been significant amount of attention to this mismatch in the science education research literature, primarily with respect to experimentation and argumentation as core disciplinary means of assessing ideas. In this article, we call attention to another aspect of scientific reasoning: a focus on causal mechanisms in explaining natural phenomena. We highlight examples and research from the history and philosophy of science to clarify what scientists mean by “mechanism” and to make the case for its centrality. We then present an excerpt from a second‐grade class in which a student provides an incorrect mechanistic explanation, and the teacher gives priority to textbook correctness. As the conversation proceeds, the student shifts from mechanistic sensemaking to quoting terminology she does not understand. We argue that attention to mechanism in the classroom would better support student reasoning and better reflect disciplinary epistemology. © 2008 Wiley Periodicals, Inc.Sci Ed93:875–891, 2009
Building a financial sector in Central and Eastern Europe
Authors: Geiger Kurt 
Published: October 2008

AbstractThe public mission of the European Bank for Reconstruction and Development (EBRD) is to foster the transition toward an open, market‐oriented financial sector. It combines private‐sector principles in making investments, building institutions, privatizing banks, and raising equity with policy dialogue with all stakeholders, lawmakers, central banks, regulators, shareholders, and clients. Wellstructured creative individual projects, tailor‐made for the specific situation and executed in a pragmatic and successful way, provide a strong demonstration effect to market participants. Today the financial sector in Central and Eastern Europe is sound, competitive, and provides the fuel for sustained economic growth. Challenges remain, however. © 2008 Wiley Periodicals, Inc.
Asian tax review: Going green in Red China
Authors: Lipsher Laurence E. 
Published: October 2008

AbstractTaxes in China are no laughing matter. The rules change often, and it takes a lot of energy to keep up. As more foreign investors enter the Chinese market, drawn by its size and dynamic entrepreneurial spirit, it can be very helpful to get frequent updates on the latest tax policies. This article talks about China's growing energy needs, increased interest in green technology, and how best to incentivize developers. The author, an expert on taxes, also provides updated information specifically from Hong Kong. © 2008 Wiley Periodicals, Inc.
Fetal abdominal cysts in the first trimester: prenatal detection and clinical significance
Authors: Sepulveda W. , Dickens K. , Casasbuenas A. , Gutierrez J. , Dezerega V. 
Published: October 2008

AbstractObjectiveIn order to determine the clinical significance of fetal abdominal cysts detected in the first trimester, we reviewed our experience with such cases collected over a 5‐year period.MethodsFive cases in which a fetal abdominal cyst was detected by ultrasound in the first trimester were identified. Information on the ultrasound findings, antenatal course and perinatal outcome was obtained in all cases.ResultsThe abdominal cyst was confirmed by an early second‐trimester scan at 14–16 weeks in all cases, at which time no associated anomalies were detected. The standard detailed second‐trimester scan at 18–22 weeks demonstrated complete resolution in three cases. These women had an uneventful antenatal course, and normal newborn infants were delivered at term. However, one of these infants had intestinal malrotation, chronic abdominal distension and midgut volvulus requiring surgery at the age of 7 months. Among the remaining two cases in which the abdominal cyst persisted, one required prenatal aspiration at 19 weeks owing to significant enlargement and resolved. The other remained stable in size and was managed conservatively, but the infant required surgery at the age of 7 weeks owing to a choledochal cyst causing intermittent episodes of acholia.ConclusionAbdominal cysts in early pregnancy often resolve spontaneously or remain small and are usually associated with a good outcome. Nevertheless, as they can also be associated with serious underlying gastrointestinal pathological conditions, close surveillance in the perinatal period is advocated. Copyright © 2008 ISUOG. Published by John Wiley & Sons, Ltd.
Umbilical venous volume flow in twin–twin transfusion syndrome
Authors: Gungor S. , Glosemeyer P. , Huber A. , Hecher K. , Baschat A. A. 
Published: October 2008

AbstractObjectivesTo examine umbilical venous volume flow (UVF) dynamics by twin status and disease severity in untreated twin–twin transfusion syndrome (TTTS).MethodsIn 70 cases of untreated TTTS, absolute UVF, UVF corrected for estimated fetal weight (UVF/kg), intertwin difference (ΔUVF/kg) and recipient to donor ratio (R/D‐UVF/kg) were calculated. Parameters for UVF were compared with respect to twin status and disease severity (early, Quintero Stages I and II; advanced, Stages III and IV).ResultsUVF/kg was higher in recipients than in donors and decreased with advancing stage in both twins (in recipients, 183.9 mL/kg/min vs. 145.6 mL/kg/min, P = 0.043; in donors, 137.5 mL/kg/min vs. 122.5 mL/kg/min, P = 0.033). Linear regression analysis demonstrated that the overall best correlation coefficient for ΔUVF/kg was obtained for the Doppler pulsatility index of the umbilical artery (t = − 4.536, P < 0.001). In advanced stage, absolute and weight‐corrected UVF were lower overall, while significant differences in intertwin volume flows persisted. The lowest flows were observed in hydropic recipients (median, 67.0 (range, 55.2–122.0) mL/kg/min vs. 180.8 (range, 59.1–565.4) mL/kg/min; P = 0.001).ConclusionsIn TTTS, UVF is significantly higher in recipients than in donors. With progression to advanced stage UVF/kg decreases in both twins as the magnitude of UVF that can be accommodated by the recipient declines. Further study of these dynamics in combination with cardiac performance parameters is warranted to refine diagnostic and prognostic assessment. Copyright © 2008 ISUOG. Published by John Wiley & Sons, Ltd.
Impacts and solutions of control packets vulnerabilities with IEEE 802.11 MAC
Authors: Rachedi Abderrezak , Benslimane Abderrahim 
Published: October 2008

AbstractIn this paper, we focus on the medium access control (MAC), particularly the IEEE 802.11 and we deal with some hidden vulnerabilities based on the control packets CTS (clear to send) and ACK (acknowledgment). Through these vulnerabilities, we show two new smart attacks which were not dealt by the solutions proposed recently like the attack based on the RTS (request to send) packet vulnerability. The malicious node can exploit these vulnerabilities on the MAC protocol, in order to corrupt the monitoring and routing processes. Furthermore, we demonstrate the attacks through algorithms and we show how vulnerabilities can be exploited and how these attacks can be implemented by the attacker. The impact of these attacks is presented through simulation and implementation. Simulation and exprimental results show the impact of the attacks on the network. In addition, the experimental results demonstrate the feasibility of these real attacks and their exploitation. These experimentations allow us to confirm the simulation's results. Furthermore, in order to prevent these attacks, the solutions based on control packet authentication are presented. We propose two kinds of the solution one is cryptography independent and the other one is cryptography dependent. The evaluation and analysis of these solutions are investigated by analytic and simulations analysis. The simulations' results of the proposed solution show that the attacks are prevented and the negative impacts are significantly reduced. In addition, the security cost of the proposed solutions are investigated. Hence, the security costs are insignificant in comparison with the negative impact of these attacks. Copyright © 2008 John Wiley & Sons, Ltd.
Local Anesthetic Hernia Repair in Overweight and Obese Patients
Authors: Reid T. D. , Sanjay P. , Woodward A. 
Published: October 2008

AbstractBackgroundInguinal hernia repair under local anesthesia (LA) has many advantages and is associated with high patient satisfaction. However, there are concerns of exceeding the maximum safe dose of LA agents in overweight and obese patients. The aim of the present study was to establish whether inguinal hernia repair could be safely performed under LA in overweight and obese patients.MethodsPatients who underwent elective LA hernia repair under a single consultant surgeon were studied retrospectively. Each patient received the same LA mixture developed at our hospital specifically for hernia repair. The mixture includes lignocaine and bupivocaine, both with adrenaline, made up to a volume of 100 ml with saline. Data were collected by case note review, and by postal and telephone surveys.ResultsA total of 125 patients who underwent LA hernia repair, in whom body mass index (BMI) was measured, were studied. Based on the World Health Organization (WHO) classification, there were 35 (28%) normal weight patients and 63 (72%) overweight (BMI ≥ 25 < 30) or obese (BMI ≥30) patients. The median BMI was 27 (range 19–38). The mean volumes of LA mixture used for each group were 58 ml and 62 ml, respectively. High day case rates of 91% and 84% were obtained for the two groups, respectively. Complications included three wound hematomas and three simple wound infections, with no significant differences between groups. One patient developed a recurrent hernia (<1%).ConclusionsLocal anesthetic inguinal hernia repair in the obese is safe and well tolerated. Use of a large volume local anesthetic mixture is recommended in overweight and obese patients.
Male rescue maintains low frequency parthenogenesis‐inducingWolbachiainfection inTrichogrammapopulations
Authors: Miura Kazuki , Yamanaka Takehiko , Suzuki Yoshito , Tagami Yohsuke , Davies Andrew Paul 
Published: October 2008

AbstractParthenogenesis‐inducing (PI)Wolbachiabacteria are reproductive parasites that cause infected (W+) female haplodiploid parasitoids to produce daughters without fertilization by males. Theoretically, PIWolbachiainfection should spread to fixation withinTrichogrammapopulations as males are no longer required to produce female offspring. Infections in some naturally occurringTrichogrammapopulations are, however, maintained at frequencies ranging from 4 to 26%. Here we describe discrete equation models to examine if the PIWolbachiainfection inTrichogrammapopulations can be maintained at relatively low frequencies by mating regularity. Model outcomes suggest the probability ofW+females mating could stabilizeWolbachiainfection frequency at low levels inTrichogrammapopulations. The primary mechanism maintaining low‐level PIWolbachiainfection inTrichogrammapopulations is reducing the survivorship from egg to adult in infected relative to uninfected females. The model successfully demonstrates that the relatively low PIWolbachiainfection frequency in host populations can be maintained by fertilization, or male rescue, of infected eggs, which avoids potentially hazardous gamete duplication that occurs duringWolbachia‐induced parthenogenesis.
Short‐term response of arbuscular mycorrhizal association to spider mite herbivory
Authors: Nishida Takaaki , Izumi Naoyuki , Katayama Noboru , Ohgushi Takayuki 
Published: October 2008

AbstractWe examined effects of aboveground herbivory by spider mites (Tetranychus urticae) on colonization and activity of arbuscular mycorrhizal fungi (AMF; Gigaspora margarita) using potted plants (Lotus japonicus). We evaluated changes in arbuscular mycorrhizal (AM) association two ways: (1) conventional trypan blue staining of mycorrhizal hyphae to examine AMF biomass in roots (mycorrhizal colonization) and (2) vital staining for a mycorrhizal enzyme (succinate dehydrogenase, SDH) to examine mycorrhizal activity (SDH activity). Mycorrhizal colonization and SDH activity started to increase 4 days after aboveground herbivory, and returned to the initial levels in the absence of mite herbivory in 7 and 12 days, respectively. These results suggest that the change in AM association in response to mite herbivory is a short‐term response.
Left atrial velocity vector imaging for the detection and quantification of left ventricular diastolic function in type 2 diabetes
Authors: Jarnert Christina , Melcher Anders , Caidahl Kenneth , Persson Hans , Rydén Lars , Eriksson Maria J. 
Published: October 2008

AbstractLeft ventricular (LV) diastolic dysfunction (DD) is diagnosed by Doppler echocardiography (DE) and Tissue Doppler imaging (TDI). Velocity vector imaging (VVI) evaluates myocardial deformation (strain). We studied left atrial (LA) deformation and volumes by VVI in relation to established Doppler‐derived indices of LV diastolic function in diabetic patients.Material:Using DE and TDI, 87 patients (males 49%; age 60±7 years) with type 2 diabetes mellitus were classified as having no (n=60), mild (n=13) or moderate (n=14) DD.Results:LA volume was larger in moderate (72.3±22.4 ml) than in mild DD (58.8±16.1 ml; p=0.01) and no DD (57.9±16.0 ml; p=0.01). LA roof strain distinguished no DD from mild and moderate DD (p=0.0073). Systolic LA strain correlated to total emptying fraction (r=0.70, p<0.0001), and inversely to LA volume (r=−0.35, p=0.0009). A cross‐validated analysis of no versus mild or moderate DD expressed by LA strain revealed a positive predictive value of 48% and negative of 84%.Conclusion:LA strain by VVI is impaired in patients with type 2 diabetes mellitus and mild or moderate LV DD. LA strain seems of value in distinguishing normal from abnormal diastolic function. VVI offers new information on regional LA function and LA volumes but has too limited discriminative power to detect early LV DD.
The Spectrum of Periodic Jacobi Matrices with Slowly Oscillating Diagonal Terms
Authors: Martíinez Carmen 
Published: October 2008

AbstractWe study the spectrum of periodic Jacobi matrices. We concentrate on the case of slowly oscillating diagonal terms and study the behaviour of the zeros of the associated orthogonal polynomials in the spectral gap. We find precise estimates for the distance from single eigenvalues of truncated matrices in the spectral gap to the diagonal entries of the matrix. We include a brief numerical example to show the exactness of our estimates.
Lamé Equation, Quantum Euler Top and Elliptic Bernoulli Polynomials
Authors: Grosset M.-P. , Veselov A. P. 
Published: October 2008

AbstractA generalization of the odd Bernoulli polynomials related to the quantum Euler top is introduced and investigated. This is applied in order to compute the coefficients of the spectral polynomials for the classical Lamé operator.
Spectral Multipliers for Laplacians Associated with some Dirichlet Forms
Authors: Carbonaro Andrea , Mauceri Giancarlo , Meda Stefano 
Published: October 2008

AbstractLet be the self-adjoint operator associated with the Dirichlet formwhere ϕ is a positive C2 function, dλϕ = ϕdλ and λ denotes Lebesgue measure on ℝd. We study the boundedness on Lp(λϕ) of spectral multipliers of . We prove that if ϕ grows or decays at most exponentially at infinity and satisfies a suitable ‘curvature condition’, then functions which are bounded and holomorphic in the intersection of a parabolic region and a sector and satisfy Mihlin-type conditions at infinity are spectral multipliers of Lp(λϕ). The parabolic region depends on ϕ, on p and on the infimum of the essential spectrum of the operator on L2(λϕ). The sector depends on the angle of holomorphy of the semigroup generated by on Lp(λϕ).