Search

Chronic hemodialysis patients exhibit an excessive cardiovascular risk and a marked increase in both thromboembolism and bleeding episodes. Factor XI inhibition may provide anticoagulation, with a low risk of bleeding, and several factor XI inhibitors, including fesomersen, an antisense oligonucleotide, are under development. Recently, a phase 2 study of fesomersen showed a good safety profile in chronic hemodialysis patients and suggested that clotting rates of the arteriovenous fistula and the dialysis circuit are lower.

Social role theory posits that binary gender gaps in agency and communion should be larger in lessegalitarian countries, reflecting these countries’ more pronounced sex-based power divisions. Conversely, evolutionary and self-construal theorists suggest that gender gaps in agency and communion should be larger in moreegalitarian countries, reflecting the greater autonomy support and flexible self-construction processes present in these countries. Using data from 62 countries (N= 28,640), we examine binary gender gaps in agentic and communal self-views as a function of country-level objective gender equality (the Global Gender Gap Index) and subjective distributions of social power (the Power Distance Index). Findings show that in more egalitarian countries, gender gaps in agency are smaller and gender gaps in communality are larger. These patterns are driven primarily by cross-country differences in men’s self-views and by the Power Distance Index (PDI) more robustly than the Global Gender Gap Index (GGGI). We consider possible causes and implications of these findings.

Comparing companies can be useful for various purposes. Despite the widespread use of industry classification systems as a peer selection standard, these have been criticized for various reasons. Financial statements, however, offer a promising alternative to such classification systems. They are standardized, widely available, and offer deep insights into the nature of the company. In this paper, we present a graph distance metric for financial statements using the earth mover's distance. When using the distance metric on real‐world tasks such as peer identification and industry classification, it shows promising results in terms of accuracy and computational efficiency.

Training healthcare physicians to perform intestinal ultrasound (IUS) during outpatient visits with equal accuracy as radiologists could improve clinical management of IBD patients. We aimed to assess whether a healthcare-physician can be trained to perform IUS, with equal accuracy compared with experienced radiologists in children with iBD, and to assess inter-observer agreement. Consecutive children, 6 to 18 years with IBD or suspicion of IBD, who underwent ileo-colonoscopy were enrolled. iUS was performed independently by a trained healthcare-physician and a radiologist in 1 visit. Training existed of an international training curriculum for IUS. Operators were blinded for each other's IUS, and for the ileocolonoscopy. Difference in accuracy of IUS by the healthcare-physician and radiologist was assessed using areas under the ROC curve (AUROC). Inter-observer variability was assessed in terminal ileum (TI), transverse colon (TC) and descending-colon (DC), for disease activity (ie, bowel wall thickness [BWT] >2 mm with hyperaemia or fat-proliferation, or BWT >3 mm). We included 73 patients (median age 15, interquartile range [IQR]:13–17, 37 [51%] female, 43 [58%] with Crohn disease). AUROC ranged between 0.71 and 0.81 for the healthcare-physician and between 0.67 and 0.79 for radiologist (P>0.05). Inter-observer agreement for disease activity per segment was moderate (K: 0.58 [SE: 0.09], 0.49 [SE: 0.12], 0.52 [SE: 0.11] respectively for TI, TC, and DC). A healthcare- physician can be trained to perform IUS in children with IBD with comparable diagnostic accuracy as experienced radiologists. The interobserver agreement is moderate. Our findings support the usage of IUS in clinical management of children with IBD.

Chronic kidney disease (CKD) triggers the risk of developing uremic cardiomyopathy as characterized by cardiac hypertrophy, fibrosis and functional impairment. Traditionally, animal studies are used to reveal the underlying pathological mechanism, although variable CKD models, mouse strains and readouts may reveal diverse results. Here, we systematically reviewed 88 studies and performed meta-analyses of 52 to support finding suitable animal models for future experimental studies on pathological kidney-heart crosstalk during uremic cardiomyopathy. We compared different mouse strains and the direct effect of CKD on cardiac hypertrophy, fibrosis and cardiac function in “single hit” strategies as well as cardiac effects of kidney injury combined with additional cardiovascular risk factors in “multifactorial hit” strategies. In C57BL/6 mice, CKD was associated with a mild increase in cardiac hypertrophy and fibrosis and marginal systolic dysfunction. Studies revealed high variability in results, especially regarding hypertrophy and systolic function. Cardiac hypertrophy in CKD was more consistently observed in 129/Sv mice, which express two instead of one renin gene and more consistently develop increased blood pressure upon CKD induction. Overall, “multifactorial hit” models more consistently induced cardiac hypertrophy and fibrosis compared to “single hit” kidney injury models. Thus, genetic factors and additional cardiovascular risk factors can “prime” for susceptibility to organ damage, with increased blood pressure, cardiac hypertrophy and early cardiac fibrosis more consistently observed in 129/Sv compared to C57BL/6 strains.

Patients with CKD display a significantly higher risk of cardiovascular and thromboembolic complications, with around half of patients with advanced CKD ultimately dying of cardiovascular disease. Paradoxically, these patients also have a higher risk of hemorrhages, greatly complicating patient therapy. Platelets are central to hemostasis, and altered platelet function resulting in either platelet hyper- or hyporeactivity may contribute to thrombotic or hemorrhagic complications. Different molecular changes have been identified that may underlie altered platelet activity and hemostasis in CKD. In this study, we summarize the knowledge on CKD-induced aberrations in hemostasis, with a special focus on platelet abnormalities. We also discuss how prominent alterations in vascular integrity, coagulation, and red blood cell count in CKD may contribute to altered hemostasis in these patients who are high risk. Furthermore, with patients with CKD commonly receiving antiplatelet therapy to prevent secondary atherothrombotic complications, we discuss antiplatelet treatment strategies and their risk versus benefit in terms of thrombosis prevention, bleeding, and clinical outcome depending on CKD stage. This reveals a careful consideration of benefits versus risks of antiplatelet therapy in patients with CKD, balancing thrombotic versus bleeding risk. Nonetheless, despite antiplatelet therapy, patients with CKD remain at high cardiovascular risk. Thus, deep insights into altered platelet activity in CKD and underlying mechanisms are important for the optimization and development of current and novel antiplatelet treatment strategies, specifically tailored to these patients who are high risk. Ultimately, this review underlines the importance of a closer investigation of altered platelet function, hemostasis, and antiplatelet therapy in patients with CKD.

Chronic kidney disease (CKD) induces modifications in lipid and lipoprotein metabolism and homeostasis. These modifications can promote, modulate and/or accelerate CKD and secondary cardiovascular disease (CVD). Lipid and lipoprotein abnormalities — involving triglyceride-rich lipoproteins, LDL and/or HDL — not only involve changes in concentration but also changes in molecular structure, including protein composition, incorporation of small molecules and post-translational modifications. These alterations modify the function of lipoproteins and can trigger pro-inflammatory and pro-atherogenic processes, as well as oxidative stress. Serum fatty acid levels are also often altered in patients with CKD and lead to changes in fatty acid metabolism — a key process in intracellular energy production — that induce mitochondrial dysfunction and cellular damage. These fatty acid changes might not only have a negative impact on the heart, but also contribute to the progression of kidney damage. The presence of these lipoprotein alterations within a biological environment characterized by increased inflammation and oxidative stress, as well as the competing risk of non-atherosclerotic cardiovascular death as kidney function declines, has important therapeutic implications. Additional research is needed to clarify the pathophysiological link between lipid and lipoprotein modifications, and kidney dysfunction, as well as the genesis and/or progression of CVD in patients with kidney disease.

IMPORTANCE: The incidence rates of keratinocyte cancer are increasing globally; however, the incidence rates of cutaneous squamous cell carcinoma (cSCC) in situ and the risk of developing subsequent invasive cSCC remain unknown. OBJECTIVE: To estimate annual population-based age-standardized incidence rates of histopathologically confirmed cSCC in situ stratified by sex, age, and body site and to assess the risk of developing invasive cSCC among patients with cSCC in situ compared with the general population. DESIGN, SETTING, AND PARTICIPANTS: This nationwide epidemiological population-based cohort study used cancer registry data to identify all patients with a first incident of histopathologically confirmed cSCC in situ between January 1, 1989, and December 31, 2017. In addition, all patients with cSCC in situ who subsequently had a first incident of invasive cSCC were identified up to June 11, 2019. Data were analyzed between March 18 and November 12, 2019. MAIN OUTCOMES AND MEASURES: Age-standardized incidence rates per year for cSCC in situ, standardized to the 2013 edition of the European Standard Population, were calculated by sex, age, and body site. Cumulative risks, standardized incidence ratios, and absolute excess risks were calculated to assess the risk of invasive cSCC in patients with cSCC in situ compared with the general population. RESULTS: In this population-based cohort study of 88 754 patients with a first incident of cSCC in situ between January 1, 1989, and December 31, 2017, 58.8% were women; the median age was 75 years (interquartile range [IQR], 67-82 years) for women and 73 years (IQR, 65-80 years) for men. Increasing incidence rates were observed, with the highest incidence rates in 2017 among women in general (71.7 cases per 100 000 person-years) and among men 80 years and older (540.9 cases per 100 000 person-years). The most common body site among women was the face (15.9 cases per 100 000 person-years) and among men was the scalp and/or neck (12.3 cases per 100 000 person-years). After 5 years of follow-up, among patients with cSCC in situ, the cumulative risk of developing an invasive cSCC at any anatomic location was 11.7% (95% CI, 11.6%-11.9%) in men and 6.9% (95% CI, 6.8%-7.0%) in women (P < .001). The standardized incidence ratio was highest in the first year of follow-up among both men (16.6; 95% CI, 15.7-17.5) and women (15.1; 95% CI, 14.2-16.1). CONCLUSIONS AND RELEVANCE: This study reports the first nationwide incidence rates of cSCC in situ to date. The increasing incidence rates of cSCC in situ and the high risk of developing invasive cSCC among patients with cSCC in situ may increase the health care burden associated with precursors of keratinocyte cancer and highlight the need to include cutaneous skin cancer precursor lesions when exploring policies to address skin cancer care.

Supplemental Digital Content is available in the text.

A symposium on kidney stones and mineral metabolism held on December 2017 in Brussels, Belgium was the first international multidisciplinary conference of the International Collaborative Network on Kidney Stones and Mineral Metabolism. This meeting addressed epidemiology, underlying pathophysiological mechanisms, genetics, pathological, as well as clinical and research topics. The participants included clinicians and recognized experts in the field from Europe and the United States interacted closely during the symposium which promoted a chance to explore new frontiers in the field of kidney stone disease. This manuscript summarizes some of the major highlights of the meeting.

With the incidence and impact of atherosclerotic cardiovascular disease and its clinical manifestations still rising, therapeutic options that target the causal mechanisms of this disorder are highly desired. Since the CANTOS trial (Canakinumab Antiinflammatory Thrombosis Outcome Study) has demonstrated that lowering inflammation can be beneficial, focusing on mechanisms underlying inflammation, for example, leukocyte recruitment, is feasible. Being key orchestrators of leukocyte trafficking, chemokines have not lost their attractiveness as therapeutic targets, despite the difficult road to drug approval thus far. Still, innovative therapeutic approaches are being developed, paving the road towards the first chemokine-based therapeutic against inflammation. In this overview, recent developments for chemokines and for the chemokine-like factor MIF (macrophage migration inhibitory factor) will be discussed.

Supplemental Digital Content is available in the text.

This paper analyzes the effect of the offset mismatch in time-interleaved analog-to-digital converter (TI-ADC) circuits on bit error rate (BER) performance of a receiver for pulse amplitude-modulated or quadrature amplitude-modulated signals in orthogonal frequency division multiplexed systems. Exact BER expressions, as well as simplified BER expressions that hold for high signal-to-noise ratios (SNRs) and large offset mismatch values only, are derived. From the obtained exact BER expressions, a condition is established on the offset mismatch level, under which the BER performance shows an error floor at high SNRs. Numerical results further show that if we keep the offset mismatch level below 25% of the threshold above, which the offset mismatch causes an error floor, there is essentially no BER performance degradation compared with the offset-mismatch free case. Our analysis further evinces that the tolerable level of the offset mismatch is proportional to the square-root of the number of sub-ADCs, indicating that as opposed to what might be expected, the offset mismatch level that can be tolerated actually increases with the number of sub-ADCs. [ABSTRACT FROM PUBLISHER]

Supplemental Digital Content is available in the text.

Ondanks dalende werkloosheidscijfers, blijft het aantal bijstandsgerechtigden alsmaar groeien. Hoe kunnen de uitstroomcijfers omhoog? Wat helpt: benut de kansen op arbeidsmarkt beter. Want die zijn er zeker, ook voor deze doelgroep. Verder kunnen technologie en data slimmer ingezet worden en professionals ontketend.

Context. Solar-like oscillations have been observed in numerous red giants from ground and from space. An important question arises: could we expect to detect non-radial modes probing the internal structure of these stars?

Context. We search for new variable B-type pulsators in the CoRoT data assembled primarily for planet detection, as part of CoRoT's additional programme.

Context. Observations suggest that a relationship exists between the driving mechanism of roAp star pulsations and the heavy element distribution in these stars.

We perform seismic modelling of the massive $\beta\,$Cep star EN Lacertae. The starting point of our analysis is the spectroscopic mode identification recently performed. To this, we add a new updated photometric mode identification based upon a non-adiabatic description of the eigenfunctions in the outer atmosphere. Both mode identifications agree and this allows us to fine-tune the stellar parameters of EN Lacertae with unprecedented precision. This is done by producing a huge amount of stellar models with different parameters and selecting those that fulfill the frequency values and the mode identification. Our study is the first one of its kind in which a reconcilation between observed pulsational characteristics and theoretical models can be achieved at a level that allows accurate determination of the basic stellar parameters of a massive oscillator. We derive a mass of $M=9.62\pm 0.11\,M_\odot$and an age of 15.7 million years if we assume that convective overshooting does not occur.

We present ground-based high-resolution high $S/N$spectra of the slowly pulsating B star HD?147394. Two frequencies are clearly found in the moments of the Si?II 4128-4130 doublet: $f_1=0.8008$c?d-1and $f_2=0.7813$c?d-1. The frequency f1is also found in the HIPPARCOS data. A third frequency is also present in our spectroscopic data: $f_3=0.7175$c?d-1or its aliases due to the time sampling. A mode identification is performed by means of a new version of the moment method optimized for multiperiodic signals. It points towards several equivalent solutions of non-axisymmetric $\ell \le 3$for all three modes. We have too limited information to perform seismic modelling at this stage, but we do show that the different possibilities for the mode identifications are compatible with pulsational models for SPBs.

We present an improved version of the method of photometric mode identification of Heynderickx et al. ([CITE]). Our new version is based on the inclusion of precise non-adiabatic eigenfunctions determined in the outer stellar atmosphere according to the formalism recently proposed by Dupret et al. ([CITE]). Our improved photometric mode identification technique is therefore no longer dependent on ad hoc parameters for the non-adiabatic effects. It contains the complete physical conditions of the outer atmosphere of the star, provided that rotation does not play a key role. We apply our method to the two slowly pulsating B stars HD 74560 and HD 138764 and to the ßCephei star EN (16) Lac. Besides identifying the degree $\ell$of the pulsating stars, our method is also a tool for improving the knowledge of stellar interiors and atmospheres, by imposing constraints on parameters such as the metallicity and the mixing-length parameter a(a procedure we label non-adiabatic asteroseismology).

Some recent observations of the abundances of s-process, r-process, and αelements in metal-poor stars have led to a new scenario for their formation. According to this scenario, these stars were born in a globular cluster and accreted the s-process enriched gas expelled by cluster stars of higher-mass, thereby modifying their surface abundances. Later on, these polluted stars evaporated from the globular cluster to constitute an important fraction of the current halo population. In addition, there are now many direct observations of abundance anomalies not only in globular cluster giant stars but also in subgiant and main-sequence stars. Accretion again provides a plausible explanation for (at least some of) these peculiarities. Here we investigate further the efficiency of the accretion scenario. We find that in concentrated clusters with large escape velocities, accretion is very efficient and can indeed lead to major modifications of the stellar surface abundances.

Supplemental Digital Content is available in the text.

De mallet thumb is een zeldzaam letsel van de duim, dat gemakkelijk kan worden gemist. Tot op heden is er geen consensus over de diagnostiek en behandeling van dit letsel, conservatief of operatief. Wij presenteren een casus met de gedachtegang omtrent de diagnostiek en behandeling. Verder geven wij het belang aan van het tijdig herkennen van dit specifieke letsel. The mallet thumb is an injury to the thumb that is relatively rare and it may be missed as a diagnosis. There is no consensus as to how to confirm the diagnosis, nor is it clear whether conservative or operative treatment is superior. We present a case report discussing our diagnostic workup and treatment. Furthermore, we emphasize the importance to recognize this specific injury.

Context. The detection with CoRoT of solar-like oscillations in nearly 800 red giants in the first 150-days long observational run paves the way for detailed studies of populations of galactic-disk red giants.Aims. We investigate which information on the observed population can be recovered by the distribution of the observed seismic constraints: the frequency of maximum oscillation power (?max) and the large frequency separation (??).Methods. We propose to use the observed distribution of ?max?and of ?? as a tool for investigating the properties of galactic red-giant stars through comparison with simulated distributions based on synthetic stellar populations.Results. We can clearly identify the bulk of the red giants observed by CoRoT as red-clump stars, i.e. post-flash core-He-burning stars. The distribution of ?max?and of ?? gives us access to the distribution of the stellar radius and mass, and thus represent a most promising probe of the age and star formation rate of the disk, and of the mass-loss rate during the red-giant branch.Conclusions. CoRoT observations are supplying seismic constraints for the most populated class of He-burning stars in the galactic disk. This opens a new access gate to probing the properties of red-giant stars that, coupled with classical observations, promises to extend our knowledge of these advanced phases of stellar evolution and to add relevant constraints to models of composite stellar populations in the Galaxy.

Understanding transport processes inside stars is one of the main goals of asteroseismology. Chemical turbulent mixing can affect the internal distribution of μnear the energy generating core, having an effect on the evolutionary tracks similar to that of overshooting. This mixing leads to a smoother chemical composition profile near the edge of the convective core, which is reflected in the behavior of the buoyancy frequency and, therefore, in the frequencies of gravity modes. We describe the effects of convective overshooting and turbulent mixing on the frequencies of gravity modes in B-type main sequence stars. In particular, the cases of p-g mixed modes in βCep stars and high-order modes in SPBs are considered. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

We investigate how the frequencies of gravity modes depend on the detailed properties of the chemical composition gradient that develops near the core of main-sequence stars and, therefore, on the transport processes that are able to modify the μprofile in the central regions. We show that in main-sequence models, similarly to the case of white dwarfs, the periods of high-order gravity modes are accurately described by a uniform period spacing superposed to an oscillatory component. The periodicity and amplitude of such a component are related, respectively, to the location and sharpness of the μgradient. We briefly discuss and interpret, by means of this simple approximation, the effect of turbulent mixing near the core on the periods of both high-order and low-order g modes, as well as of modes of mixed pressure-gravity character. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Two new homobimetallic ruthenium-arene complexes [(p-cymene)Ru(μ-Cl)3RuCl(η2-C2H4)(L)], where L=1,3-bis(2,4,6-trimethylphenyl)imidazolin-2-ylidene (3a) or 1,3-bis(2,4,6-trimethylphenyl)-4,5-dichloroimidazolin-2-ylidene (3b), were isolated in high yields upon heating a toluene solution of [RuCl2(p-cymene)]2 with 1 equivalent of carbene ligand under an ethylene atmosphere. They were characterized by NMR and TGA. Their catalytic activity was investigated in the atom transfer radical polymerization of vinyl monomers. In the polymerization of methyl methacrylate, complex 3a displayed faster reaction rates than 3b and the related phosphine-based complex 2a (L=tricyclohexylphosphine), although control was more effective with the latter catalyst. When n-butyl acrylate or styrene served as monomer, a major shift of reactivity was observed between complex 2a that promoted controlled radical polymerization, and complexes 3a or 3b that favored metathetical coupling. Further homocoupling experiments with various styrene derivatives confirmed the outstanding aptitude of complex 3a (and to a lesser extent of 3b) to catalyze olefin metathesis reactions. Contrary to monometallic ruthenium-arene complexes of the [RuCl2(p-cymene)(L)] type, the new homobimetallic species did not require the addition of a diazo compound or visible light illumination to initiate the ring-opening metathesis of norbornene or cyclooctene. When α,ω-dienes were exposed to 3a or 3b, a mixture of cycloisomerization and ring-closing metathesis products was obtained in a non-selective way. Addition of a terminal alkyne co-catalyst enhanced the metathetical activity while completely repressing the cycloisomerization process. Thus, quantitative conversions of diethyl 2,2-diallylmalonate and N,N-diallyltosylamide were achieved within 2 4;h at room temperature using 2 mol % of catalyst precursor 3 a and 6 mol % of phenylacetylene.

Abstract??A virtual test facility (VTF) for studying the three-dimensional dynamic response of solid materials subject to strong shock and detonation waves has been constructed as part of the research program of the Center for Simulating the Dynamic Response of Materials at the California Institute of Technology. The compressible fluid flow is simulated with a Cartesian finite volume method and treating the solid as an embedded moving body, while a Lagrangian finite element scheme is employed to describe the structural response to the hydrodynamic pressure loading. A temporal splitting method is applied to update the position and velocity of the boundary between time steps. The boundary is represented implicitly in the fluid solver with a level set function that is constructed on-the-fly from the unstructured solid surface mesh. Block-structured mesh adaptation with time step refinement in the fluid allows for the efficient consideration of disparate fluid and solid time scales. We detail the design of the employed object-oriented mesh refinement framework AMROC and outline its effective extension for fluid?structure interaction problems. Further, we describe the parallelization of the most important algorithmic components for distributed memory machines and discuss the applied partitioning strategies. As computational examples for typical VTF applications, we present the dynamic deformation of a tantalum cylinder due to the detonation of an interior solid explosive and the impact of an explosion-induced shock wave on a multi-material soft tissue body.

New imidazolium and imidazolinium salts were synthesized and their ability to act as stable N-heterocyclic carbene (NHC) ligand precursors was investigated in various ruthenium-catalyzed processes. Thus, 1,3- diarylimidazol(in)ium chlorides bearing the phenyl, 1-naphthyl, 4-biphenyl, 3,5-dimethylphenyl, 2-tolyl, 2,6- dimethylphenyl, 2,4,6-trimethylphenyl (mesityl), and 2,6-diisopropylphenyl substituents were prepared. They were combined with the [RuCl2(p-cymene)]2 dimer and potassium tert-butoxide or sodium hydride to generate the corresponding ruthenium-arene complexes [RuCl2(p-cymene)(NHC)] in situ. The catalytic activity of all these species was investigated in the photoinduced ring-opening metathesis polymerization (ROMP) of norbornene and cyclooctene. Results from this study showed that the C4-C5 double bond in the imidazole ring of the NHC ligands was not crucial to achieve high catalytic efficiencies. The presence or the absence of alkyl groups on the ortho positions of the phenyl rings had a more pronounced influence. Blocking all the ortho positions was a requisite for obtaining efficient catalysts. Failure to do so probably resulted in the ortho-metallation of the carbene ligand, thereby altering the coordination sphere of the ruthenium active centers. Catalytic screenings were also carried out with the various imidazol(in)ium salts to evaluate their ability at promoting the cyclopropanation of styrene and cyclooctene with ethyl diazoacetate. Under the experimental conditions adopted, the exact nature of the N,N'-diaryl groups had very little influence on the outcome of these reactions. The imidazolium salts were further probed as catalyst modifiers for the Atom Transfer Radical Addition (ATRA) of carbon tetrachloride to styrene. Some species displayed a dual activity and promoted both olefin metathesis and ATRA.

This contribution considers turbo synchronization, that is to say, the use of soft data information to estimate parameters like carrier phase, frequency, or timing offsets of a modulated signal within an iterative data demodulator. In turbo synchronization, the receiver exploits the soft decisions computed at each turbo decoding iteration to provide a reliable estimate of some signal parameters. The aim of our paper is to show that such "turbo-estimation" approach can be regarded as a special case of the expectation-maximization (EM) algorithm. This leads to a general theoretical framework for turbo synchronization that allows to derive parameter estimation procedures for carrier phase and frequency offset, as well as for timing offset and signal amplitude. The proposed mathematical framework is illustrated by simulation results reported for the particular case of carrier phase and frequency offsets estimation of a turbo-coded 16-QAM signal.

In this paper, we derive the Cramér-Rao bound (CRB) for joint carrier phase, carrier frequency, and timing estimation from a noisy linearly modulated signal with encodeddata symbols. We obtain a closed-form expression for the CRB in terms of the marginal a posteriori probabilities of the coded symbols, allowing efficient numerical evaluation of the CRB for a wide range of coded systems by means of the BCJR algorithm. Simulation results are presented for a rateturbo code combined with QPSK mapping. We point out that the synchronization parameters for the coded system are essentially decoupled. We find that, at the normal (i.e., low) operating SNR of the turbo-coded system, the trueCRB for codedtransmission is (i) essentially the same as the modifiedCRB and (ii) considerably smaller than the trueCRB for uncodedtransmission. Comparison of actual synchronizer performance with the CRB for turbo-coded QPSK reveals that a "code-aware" soft-decision-directed synchronizercan perform very closely to this CRB, whereas "code-unaware" estimators such as the conventional non-data-aidedalgorithm are substantially worse; when operating on coded signals, the performance of the latter synchronizers is still limited by the CRB for uncoded transmission.

An efficient and highly stereoselective synthetic procedure is reported for the construction of symmetrical and unsymmetrical (E)-polymethoxystilbene and (E)-polyhydroxystilbene derivatives. The strategy rests on a cross-metathesis reaction catalyzed by stable, well-defined (alkylidene)ruthenium complexes, in particular the second-generation Grubbs catalyst [RuCl2(=CHPh)(SIMes)(PCy3)] [SIMes = 1,3-bis(2,4,6-trimethylphenyl)imidazolidin-2-ylidene]. The metathesis of unprotected phenolic styrenes is illustrated by the synthesis of the important phytoalexins (E)-3,4',5-trihydroxystilbene (resveratrol) and (E)-3,3',4,5'-tetrahydroxystilbene(piceatannol). (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)

In a previous article we proposed an algebraic setting in which to perform harmonic analysis on noncompact, nondiscrete quantum groups and in particular, on quantum E(2). In the present paper we shall explicitly construct Fourier transforms between quantum E(2) and its Pontryagin dual, involving Hahn—Exton q-Bessel functions as kernel, prove Plancherel and inversion formulas, etc. We also develop a theory of q-Hankel transformation of entire functions, based on the definition proposed by Koornwinder and Swarttouw.

We perform a detailed seismic study of the $\beta$ Cep star HD 129929. Our analysis is based on the recent derivation of six pulsation frequencies. These frequencies are unambiguously identified from the seismic modelling and the photometric amplitudes to be the radial fundamental, the $\ell=1$, $p_1$ triplet, two consecutive components of the $\ell=2$, $g_1$ quintuplet. A non-adiabatic analysis allows us to constrain the metallicity of the star to $Z \in [0.016, 0.022]$. In addition, the fitting of three independent frequencies, two of which correspond to axisymmetric ($m=0$) modes, allows us to constrain the core overshooting parameter to $\alpha_{\rm ov}=0.10\,\pm\,0.05$, as well as the other global parameters of the star. Finally, from the observation of the $\ell=1$ triplet and part of the $\ell=2$ quintuplet, we derive constraints on the internal rotation of this star.

The ring-opening metathesis polymerization (ROMP) of two optically active 2,3-dicarboalkoxynorbornadienes derived from (S)-(−)-2-methyl-1-butanol and (R)-(−)-2-butanol were carried out in the presence of the [RuCl2(p-cymene)]2 catalyst precursor activated by trimethylsilyldiazomethane (TMSD). ¹H and ¹³C NMR analyses showed that a high degree of stereoregularity was achieved, and homonuclear proton−proton COSY spectroscopy indicated that the major trans fractions of the polymers were most likely isotactic, while the minor cis fractions were syndiotactic. Ring-opened metathesis polymers were also made from 2,3-dicarbomethoxynorbornadiene and exo,exo-2,3-dicarbomethoxy-5-norbornene. They were hydrogenated into the corresponding polynorbornanes using diimide. The NMR spectra of the reduced materials confirmed that the unsaturated parent polymers had an all-trans highly isotactic microstructure. A tentative mechanism involving arene loss, carbene formation, and monomer chelation is proposed to account for the observed stereoselectivities.