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A chiral diene-rhodium complex was found to catalyze the reaction of 1,6-enynes with ArZnCl to give high yields of 2-(alkylidene)cyclopentylmethylzincs with high enantioselectivity (95-99 % ee). The enantioenriched alkylzincs were readily converted in a one-pot approach into a wide variety of functionalized products by taking advantage of their unique reactivity. The catalytic cylcle involves arylrhodation of alkyne, intramolecular alkenylrhodation of alkene, and transmetalation of the alkyl-rhodium intermediate into alkylzinc.

SUMMARY An important and often discussed research problem in statistics is how to compare several populations; examples arise in medical science, engineering, finance and other fields. Often population means or medians are compared. However, one population may have a higher mean income, for example, because of a small number of super-rich individuals; the mean therefore may not reflect the wealth of the general population. Instead, an index of the degree of stochastic dominance of one population over another would better reflect their relative wealth. Currently, we can estimate such an index under restrictive conditions, but there is no generic estimator with a known asymptotic distribution. In this paper, we suggest linking the populations via the density ratio model. Under this model, we develop an empirical likelihood estimator and establish its asymptotic normality. In addition, we improve the estimation efficiency by examining the similarities between the populations. Furthermore, we provide a valid bootstrap method for hypothesis testing and the construction of confidence intervals. Simulation experiments show that the proposed estimator substantially improves the estimation efficiency and power of the test, and leads to confidence intervals with satisfactorily precise coverage probabilities. It is also robust with respect to mild model misspecification. Two examples are given to demonstrate the usefulness of both the method and the concept.

A compact and efficient self-powered micro-power system, composing of energy harvesting unit and electric power conversion unit is the most promising candidate to support widely distributed information equipment to overcome the constraints of wired and portable power supply. However, current works fail to provide an integrated and optimized system, which suffer from large attenuation loss. Thus, the output power is too micro for board applications with unsatisfied efficiency. To overcome those problems, this paper proposes a novel PCB integrated self-powered micro-electric generator for vehicle engine vibration harvesting. The generator windings and power conversion unit are implemented on same PCB substrate. The micro-generator has the output of ± 2341.85mV AC at 52.3Hz. An all GaN high frequency dual-boost AC-DC converter with boundary conduction mode is employed with impedance matching for maximum power transferring. It also utilizes the output inductance of micro-generator as boost inductor and sensing inductor. The peak output efficiency of the converter reaches to 83% at 3.3V/21.35mW output, which is much higher than state-of-art.

The internal threat to nuclear security is one of the most serious problems in the physical protection supervision of spent fuel reprocessing plants. Both insiders and nuclear security departments have obvious characteristics of situational decision making and even irrational decision making. Combined with Game theory and RDEU theory, the RDEU Game model of insiders and nuclear security departments was constructed to analyze the existence of equilibrium solutions of two-way strategies under different emotional states. From a dynamic point of view, the influence and change process of emotion on participants’ decision-making behavior were analyzed. Then, the model was numerically simulated to verify its accuracy and effectiveness, which showed that different emotional states and intensities would not only affect the final result of evolutionary equilibrium, but also change the evolution speed of the strategies. In addition, compared with insiders, the intensity of pessimism in the nuclear security department had a greater impact on the game equilibrium. Finally, we present some reasonable recommendations to prevent and protect nuclear security events at spent fuel reprocessing plants by strengthening the emotional supervision and guidance of insiders and the nuclear security department.

Sample surveys are widely used to obtain information about totals, means, medians and other parameters of finite populations. In many applications, similar information is desired for subpopulations such as individuals in specific geographic areas and socio‐demographic groups. When the surveys are conducted at national or similarly high levels, a probability sampling can result in just a few sampling units from many unplanned subpopulations at the design stage. Cost considerations may also lead to low sample sizes from individual small areas. Estimating the parameters of these subpopulations with satisfactory precision and evaluating their accuracy are serious challenges for statisticians. To overcome the difficulties, statisticians resort to pooling information across the small areas via suitable model assumptions, administrative archives and census data. In this paper, we develop an array of small area quantile estimators. The novelty is the introduction of a semiparametric density ratio model for the error distribution in the unit‐level nested error regression model. In contrast, the existing methods are usually most effective when the response values are jointly normal. We also propose a resampling procedure for estimating the mean square errors of these estimators. Simulation results indicate that the new methods have superior performance when the population distributions are skewed and remain competitive otherwise.

Asymmetric total syntheses of insulicolide A, 14- O-acetylinsulicolide A, 6β,9α-dihydroxy-14- p-nitrobenzoyl cinnamolide, and 7α,14-dihydroxy-6β- p-nitrobenzoylconfertifolin have been achieved for the first time. The key steps in the synthesis include: (1) an iridium-catalyzed enantioselective polyene cyclization to construct the drimane core bearing two all-carbon quaternary chiral centers at C4 and C10 and (2) a cascade ozonolysis of the phenol ring to form the lactone fragment of the target molecules.

The stereoselective construction of the CDEFGH ring system of lancifodilactone G is described. The key steps in this synthesis are (i) ring-closing metathesis for formation of the oxa-bridged eight-membered ring; (ii) an intramolecular Pauson-Khand reaction for construction of the sterically congested F ring; and (iii) sequential cross-metathesis, hydrogenation, and lactonization reactions for installation of the anomerically stabilized bis-spiro ketal fragment of lancifodilactone G.

Existing research on automated database operation and maintenance for the electrical industry mainly focuses on distributed and cloud platforms, and there is a lack of traditional large-scale database intelligent operation and maintenance research. This paper designs an overall operation and maintenance model framework of “intelligent perception-intelligent decision-intelligent execution”, and proposes feasible implementation plans, including: (1) Use the prophet time series forecasting model to perceive and predict important database performance indicators, and dynamically adjust the threshold of each performance indicator according to the predicted value; (2) Perform correlation analysis on abnormal indicators through the association rule model to construct “Indicators”->Operation” optimized combination operation strategy library for intelligent decision making; (3) According to the intelligent decision library, automatically restrict the associated operations under abnormal conditions to ensure the normal operation of the service and realize intelligent execution.

Gaussian mixtures of autoregressive models can be adopted to explain heterogeneous behaviour in mean, volatility, and multi-modality of the conditional or marginal distributions of time series. One important task is to infer the number of autoregressive regimes and the autoregressive orders. Information-theoretic criteria such as aic or bic are commonly used for such inference, and typically evaluate each regime/autoregressive combination separately in order to choose an optimal model. However the number of combinations can be so large that such an approach is computationally infeasible. In this article we first develop a computationally efficient regularization method for simultaneous autoregressive-order and parameter estimation when the number of autoregressive regimes is pre-determined. We then propose a regularized Bayesian information criterion (rbic) to select the number of regimes. We study asymptotic properties of the proposed methods, and investigate their finite sample performance via simulations. We show that asymptotically the rbic does not underestimate the number of autoregressive regimes, and provide a discussion on the current challenges in investigating whether and under what conditions the rbic provides a consistent estimator of the number of regimes. We finally analyze U.S. gross domestic product growth and unemployment rate data to demonstrate the proposed methods. The Canadian Journal of Statistics 45: 356–374; 2017 © 2017 Statistical Society of Canada

Novel oxazaborolidines activated by the strong acid triflimide or AlBr3 form cationic chiral catalysts. These are effective catalysts for highly regio- and enantioselective Diels–Alder reactions using substituted (E)-4-oxopent-2-enoates as dienophiles.

Asymmetric total synthesis of structurally intriguing and highly oxygenated lancifodilactone G acetate (7) has been achieved for the first time in 28 steps from a cheap commodity chemical, 2-(triisopropylsiloxy)-1,3-butadiene.

Super-paramagnetic core-shell microspheres were synthesized by ultrasonic assisted routine under low ultrasonic irradiation powers. Compared with conventional routine, ultrasonic effect could not only improve the uniformity of the core-shell structure of Fe3O4@SiO2, but shorten the synthesis time in large scale. Owing to their hydrophilicity and high surface charge, the Fe3O4@SiO2 microspheres could be dispersed well in distilled water to form homogeneous colloidal suspension. The suspensions have favorable magneto-chromatic ability that they sensitively exhibit brilliant colorful ribbons by magnetic attraction. The colorful ribbons, which distributed along the magnetic lines, make morphology of the magnetic fields become “visible” to naked eyed. Those colorful ribbons originate from strong magnetic interaction between the microspheres and magnetic fields. Furthermore, the magneto-chromatic performance is reversible as the colorful ribbons vanished rapidly with the removing of magnetic fields. The silica layer effectively enhanced the acid resistance and surface-oxidation resistance of theFe3O4@SiO2 microspheres, so they could exhibit stable magnetic nature and robust magneto-chromatic property in acid environment.

The finite Gamma mixture model is often used to describe randomness in income data, insurance data, and data from other applications. The popular likelihood approach, however, does not work for this model because the likelihood function is unbounded, and the maximum likelihood estimator is therefore not well defined. There has been much research into ways to ensure the consistent estimation of the mixing distribution, including placing an upper bound on the shape parameter or adding a penalty to the log-likelihood function. In this paper, we show that if the shape parameter in the finite Gamma mixture model is structural, then the maximum likelihood estimator of the mixing distribution is well defined and strongly consistent. We also present simulation results demonstrating the consistency of the estimator. We illustrate the application of the model with a structural scale parameter to household income data. The fitted mixture distribution leads to several possible subpopulation structures in terms of the level of disposable income.

A new species of the genus Wesmaelia Foerster, 1863, Wesmaelia longius sp. n. is described and illustrated from the Palaearctic Region of China. A key to the Chinese species of the genus Wesmaelia is provided based on the key of Papp (1995).

Controlled extraction of spin-polarized currents from the surface of topological insulators (TIs) would be an important step to use TIs as spin-electronic device materials. One way is to utilize the surface photovoltage (SPV) effect, by which the surface current may flow upon irradiation of light. To date, unipolar SPV has been observed on TIs, while the realization of ambipolar SPV is crucial for taking control over the direction of the flow. By using time-resolved photoemission, we demonstrate the ambipolar SPV realized on the TI ${\mathrm{Bi}}_{2}{\mathrm{Te}}_{3}$. The topological surface states showed downward and upward photovoltaic shifts for the $n$- and $p$-type samples, respectively. We also discerned the photogenerated carriers accumulated in the surface states for $g4\phantom{\rule{4pt}{0ex}}\ensuremath{\mu}\mathrm{s}$. We provide the keys besides the in-gap Fermi level to engineer the SPV on TIs.

Maintaining a population inversion in electron distributions is the first step towards lasing. There is a strong interest in realizing the inversion in a Dirac conical band structure, because broad-band lasing may then be realized owing to the zero-gap nature of the Dirac cone. Here we show that the population inversion can be elongated to $g7$ ps at 8 K and $g10$ ps at 300 K on the surface of a $p$-type topological insulator ${({\mathrm{Sb}}_{0.73}{\mathrm{Bi}}_{0.27})}_{2}{\mathrm{Te}}_{3}$. Time- and angle-resolved photoemission spectroscopy gives us the direct evidence for the elongated duration of the inversion in the topological surface states. We hereby provide a guideline to prolong the population inversion at finite temperatures. Our study strengthens the route toward the Dirac materials to be a lasing medium.

The angular stability of the crystals used in the monochromator is crucial for the beam position, the flux and the resolution for the synchrotron based hard X-ray beamline. In this paper, we report a performance optimization to a double-crystal monochromator (DCM) which has served for nearly 10 years at Shanghai Synchrotron Radiation Facility (SSRF). By upgrading the design of the clamping and the cooling to the 2nd crystal, the layout of the LN2 circuit, the structure of the 2nd crystal assembly and the thermal insulation as well as the temperature stabilization system, the resulted angular stability of the crystals in working condition (LN 2 circulation) tested by the angular stability of the exit beam has been greatly improved from approximately 500 nrad RMS/2 h up to better than 200 nrad RMS/2 h in vertical direction (pitch rotation of the crystals) and better than 300 nrad RMS/2 h in horizontal direction (roll rotation of the crystals) respectively, which meets the requirement by 300 nrad RMS/2 h in user experiments of the BSL-2 macromolecular crystallography beamline (P2, BL10U2).

A mechanistic study using a cyclopropylmethyl radical clock as a probe to investigate the formation of a macrolactam ring via an SmI2-mediated intramolecular Reformatsky reaction is experimentally explored. The results of our study indicate that the key SmIII-enolate intermediate is formed by cleavage of a C−Br bond in an anion-mediated β-elimination, and then eventually undergoes an intramolecular aldol condensation to form the macrolactam ring.

In dose–response studies, experiments are often carried out according to optimal designs for the purpose of accurately determining a specific effective dose (ED) level. If the interest is in the dose–response relationship over a range of ED levels, the existing optimal designs is misaligned. In this paper, we propose a two-stage sequential ED-design for this purpose. We use a small number of trials to provide a tentative estimation of the parameters. The dose levels of the subsequent trials are then selected sequentially, based on the latest model information, to maximize the efficiency of the ED estimation over several ED levels. Simulations indicate that the proposed design compares favorably with existing designs under various scenarios.

Two-parameter gamma distributions are widely used in liability theory, lifetime data analysis, financial statistics, and other areas. Finite mixtures of gamma distributions are their natural extensions, and they are particularly useful when the population is suspected of heterogeneity. These distributions are successfully employed in various applications, but many researchers falsely believe that the maximum likelihood estimator of the mixing distribution is consistent. Similarly to finite mixtures of normal distributions, the likelihood function under finite gamma mixtures is unbounded. Because of this, each observed value leads to a global maximum that is irrelevant to the true distribution. We apply a seemingly negligible penalty to the likelihood according to the shape parameters in the fitted model. We show that this penalty restores the consistency of the likelihoodbased estimator of the mixing distribution under finite gamma mixture models. We present simulation results to validate the consistency conclusion, and we give an example to illustrate the key points.

Our first-generation synthetic study towards the total synthesis of propindilactone G (1) and its analogues is reported. The key synthetic steps were an intramolecular Pauson-Khand reaction (PKR) and a vinylogous Mukaiyama reaction (VMAR). The stereoselective synthesis of the CDE ring moiety with an all-carbon quaternary center through a PKR was difficult, whilst a VMAR afforded a product with the opposite stereochemistry at the C20 position on the side chain. These results led us to redesign our synthetic strategy for the total synthesis of compound 1.

There has been a rapid progress in designing valid and effective statistical hypothesis tests for the order of a finite mixture model. In particular, EM-test for the order of the mixture model has been developed and found effective when the component distribution contains a single parameter. EM-test is found to be particularly effective and elegant for the order of normal mixture in both mean and variance. The idea behind EM-test has been found widely applicable. In this paper, we investigate the use of EM-test for the order of a finite normal mixture in the mean parameter with equal but unknown component variances. We show that for any positive integer \(m_0 \ge 2,\) the limiting distribution of the EM-test for the order of \(m_0\) against the higher order alternative is \(\chi ^2_{m_0-1}.\) A genetic example is used to illustrate the application of the EM-test.

To meet the requirements on the stability of the exit beam during the energy scanning in the multi-wavelength anomalous scattering experiments at Shanghai Synchrotron Radiation Facility (SSRF), strict specifications are placed on the double-crystal parallelism (@ pitch direction) of the double crystal monochromator (DCM) , which should be better than 0.25 ′ ′ ∕ ∘ . In this case, the specifications of the existing cryo-cooled monochromator does not meet the requirements well in the energy range 5 ∼ 6.7 keV, which affects the stability of the flux of exit beam. To solve the problem, the 2nd crystal is optimized by designing an indirect cooling method, improving the structure of flexure hinge of the fine-tuning angular mechanism and meanwhile reducing weight for related structural parts. All these methods together have effectively improved the double-crystal parallelism of the DCM. The parallelism in pitch direction is 6.3”/30°, which is about 65% better than that before the improvement (18.1”/30°). All these works have significantly consolidated the foundation of the stability improvement of the DCM exit beam.

In some applications, an experimental unit is composed of two distinct but related subunits. The response from such a unit is $(X_{1}, X_{2})$ but we observe only $Y_1 = \min\{X_{1},X_{2}\}$ and $Y_2 = \max\{X_{1},X_{2}\}$, i.e., the subunit identities are not observed. We call $(Y_1, Y_2)$ unordered paired observations. Based on unordered paired observations $\{(Y_{1i}, Y_{2i})\}_{i=1}^n$, we are interested in whether the marginal distributions for $X_1$ and $X_2$ are identical. Testing methods are available in the literature under the assumptions that $Var(X_1) = Var(X_2)$ and $Cov(X_1, X_2) = 0$. However, by extensive simulation studies, we observe that when one or both assumptions are violated, these methods have inflated type I errors or much lower powers. In this paper, we study the likelihood ratio test statistics for various scenarios and explore their limiting distributions without these restrictive assumptions. Furthermore, we develop Bartlett correction formulae for these statistics to enhance their precision when the sample size is not large. Simulation studies and real-data examples are used to illustrate the efficacy of the proposed methods., Comment: 30 pages, 1 figure

Two new species of Microplitis Förster, 1862, M.bomiensis Zhang, sp. nov., and M.paizhensis Zhang, sp. nov. from Tibet, China are described and illustrated. A key to the species of the genus Microplitis Förster from China is added.

Two new species of the genus Anisocyrta Foerster, 1863, from China are described and illustrated: Anisocyrta xiaoliyaoae Yao, sp. n. and Anisocyrta cvanachterbergi Yao, sp. n. Anisocyrta is reported from China for the first time. A key to the Palearctic species of the genus Anisocyrta is provided based on the keys of van Achterberg (1986) and Belokobylskij (1998). Type specimens of the two new species are deposited in the Beneficial Insects Institute Collection, Fujian Agriculture and Forestry University, Fuzhou, China (BIIC).

Neurolarthra Fischer, 1976, is a small braconid genus with two described species. The genus is revised using morphological characters and a phylogenetic analysis of COI sequence data; GenBank accession numbers of seven COI sequences from two species are included. A new species from Thailand is described and illustrated: N. karensharkeyae Yao n. sp. Neurolarthra Fischer and N. procera are reported for the first time from Thailand. A key to species of the genus Neurolarthra is presented.

Separatatus Chen & Wu, 1994, is reported for the first time from Thailand and one new species is described and illustrated: Separatatus xuexincheni n. sp. In addition, one species is newly recorded from Thailand (S. parallelus Zhu et al., 2017) and we transfer one species from Phasmidiasta to Separatatus: S. malaysiae (Fischer, 2006) n. comb. A key to species of the genus Separatatus is presented.

This work was financially supported by KAKENHI (Grants No. 17H06138 and No. 26800165) and the bilateral collaboration program between RFBR (Russia; Grant No. 15-52-50017) and JSPS (Japan). This work also was supported by the Spanish Ministry of Economy and Competitiveness MINECO (Project No. FIS2016-76617-P). O.E.T. and K.A.K. were supported by the Russian Science Foundation (Project No. 17-12-01047).

The asymmetric total synthesis of lancifodilactone G acetate was accomplished in 28 steps. The key steps in this synthesis include (i) an asymmetric Diels–Alder reaction for formation of the scaffold of the BC ring; (ii) an intramolecular ring-closing metathesis reaction for the formation of the trisubstituted cyclooctene using a Hoveyda–Grubbs II catalyst; (iii) an intramolecular Pauson–Khand reaction for construction of the sterically congested F ring; (iv) sequential cross-metathesis, hydrogenation, and lactonization reactions for installation of the anomerically stabilized bis-spiro ketal fragment of lancifodilactone G; and (v) a Dieckmann-type condensation reaction for installation of the A ring. The strategy and chemistry developed for the total synthesis will be useful in the synthesis of other natural products and complex molecules.

Without exception, great statisticians have penetrating statistical insight. Technical strength is likely secondary in their research, although it never hurts. In contrast, mathematical skill has been pivotal in my work, particularly in combination with my proximity to many great statistical minds. In the occasion of receiving the Gold Medal of the Statistical Society of Canada, I wish to attribute part of my success to the joy of proofs. Proofs are an indispensable ingredient in my research achievements. I hasten to add that proofs are delightful only if they help to develop innovative statistical methods: proving theorems solely for the sake of publication can be boring and a waste of time. With this preamble, I selectively present some research achievements and encourage other researchers to proudly maximize the benefits of their technical strength. The Canadian Journal of Statistics 43: 481–497; 2015 © 2015 Statistical Society of Canada Resume Inserer votre resume ici. We will supply a French abstract for those authors who can't prepare it themselves. La revue canadienne de statistique 43: 481–497; 2015 © 2015 Societe statistique du Canada

A concise total synthesis of (+)-propindilactone G, a nortriterpenoid isolated from the stems of Schisandra propinqua var. propinqua, has been achieved for the first time. The key steps of the synthesis include an asymmetric Diels-Alder reaction, a Pauson-Khand reaction, a Pd-catalyzed reductive hydrogenolysis reaction, and an oxidative heterocoupling reaction. These reactions enabled the synthesis of (+)-propindilactone G in only 20 steps. As a consequence of our synthetic studies, the structure of (+)-propindilactone G has been revised.

Genomic imprinting is a known aspect of the etiology of many diseases. The imprinting phenomenon depicts differential expression levels of the allele depending on its parental origin. When the parental origin is unknown, the expression level has a finite normal mixture distribution. In such applications, a random sample of expression levels consists of three subsamples according to the number of minor alleles an individual possesses, of which one is the mixture and the other two are homogeneous. This understanding leads to a likelihood ratio test (LRT) for the presence of imprinting. Because of the nonregularity of the finite mixture model, the classical asymptotic conclusions on likelihood-based inference are not applicable. We show that the maximum likelihood estimator of the mixing distribution remains consistent. More interestingly, thanks to the homogeneous subsamples, the LRT statistic has an elegant and rather distinct 0.5χ21 + 0.5χ22 null limiting distribution. Simulation studies confirm that the ...

This is a larger analysis of 170 alysiine sequences (13 genera) that we generated. The data were partitioned by codon position. We applied the most complex model available (GTR+I+G; Rodriguez et al. 1990) to each partition as per recommendations of Huelsenbeck and Rannala (2004). We conducted a 100-replicate ML search for the tree of highest log-likelihood and a 500-replicate ML bootstrap analysis (Felsenstein 1985). Both analyses used the default settings.

Feature selection is fundamental for modeling the high-dimensional data, where the number of features can be huge and much larger than the sample size. Since the feature space is so large, many traditional procedures become numerically infeasible. It is hence essential to first remove most apparently noninfluential features before any elaborative analysis. Recently, several procedures have been developed for this purpose, which include the sure-independent-screening (SIS) as a widely used technique. To gain computational efficiency, the SIS screens features based on their individual predicting power. In this article, we propose a new screening method via the sparsity-restricted maximum likelihood estimator (SMLE). The new method naturally takes the joint effects of features in the screening process, which gives itself an edge to potentially outperform the existing methods. This conjecture is further supported by the simulation studies under a number of modeling settings. We show that the proposed method is screening consistent in the context of ultrahigh-dimensional generalized linear models. Supplementary materials for this article are available online.

This paper puts forward a new trust model CTM (Credit Transfer Model) in the mobile P2P (Peer to Peer) network. Applying a hybrid P2P network topology structure, the CTM selects large servers in the cable network as super nodes which maintain the identity information, resource information, transaction records and trust information of ordinary nodes. The CTM simplifies the calculation of the node's trust value, identifies and suppresses the three kinds of malicious nodes in the network. And the credit transfer mechanism is proposed for the high dynamic performance of the mobile P2P network. In the simulation experiments, it shows that the model makes a good performance in the system overhead, security and transaction success rate, and can resolve some trust problem in the mobile P2P network.

It has been shown that some bacteria can attract their hosts. Our research aimed to identify cultivable bacterial isolates in the guts of sexually mature adult female and male Bactrocera tau and to evaluate their utility in trapping of B. tau.Forty-one strains of bacteria were isolated and identified from B. tau with morphological, physiological, biochemical and 16S rDNA analysis. The dominant bacterial genera shared by both females and males were Enterobacter, Providencia and Serratia. Thirteen bacterial isolates selected from female and male B. tau adults were cultured, and the attractiveness of bacterial fermented liquid and autoclaved supernatants from these strains to B. tau adults was tested. The laboratory test showed that both the autoclaved supernatants and fermented liquid could attract male and female B. tau, and the former was substantially more effective, with the autoclaved supernatants from all strains being significantly more attractive to adult B. tau. BF16, BF(12), BF23 and BF(32) were the most attractive bacteria to 8-day-old and sexually mature B. tau. Furthermore, the results of a subsequent field cage test showed that BF(12), BF23, and BF(32) were significantly more attractive to B. tau adults.These results provide useful information for the development of bacterial biocontrol agents and their application as insecticides. © 2018 Society of Chemical Industry.

In this study, photon-stimulated gas desorption yields from CuCrZr, which are used for manufacturing high-heat-load elements, were measured using a synchrotron light with a critical energy of 10.4 keV at the Shanghai Synchrotron Radiation Facility. CuCrZr samples were exposed to synchrotron radiation (SR) under both normal and grazing incidences. For comparison, a Glidcop sample was also exposed to SR under normal incidence. The experimental apparatus and measurement principles for photon desorption yield are described in this paper and the results of measurements are discussed.

Empirical-likelihood-based inference for parameters defined by the general estimating equations of Qin & Lawless (1994) remains an active research topic. When the sample size is small and/or the dimension of the accompanying estimating equations is high, the resulting confidence regions often have a lower than nominal coverage probability. In addition, the empirical likelihood can be hindered by an empty set problem. The adjusted empirical likelihood (AEL) tackles both problems simultaneously. However, the AEL confidence region with high-order precision relies on accurate estimation of the required level of adjustment. This has proved difficult, particularly in over-identified cases. In this article, we show that the general AEL is Bartlett-correctable and propose a two-stage procedure for constructing accurate confidence regions. A naive AEL is first employed to address the empty set problem, and it is then Bartlett-corrected through a resampling procedure. The finite-sample performance of the proposed method is illustrated by simulations and an example. The Canadian Journal of Statistics 43: 42–59; 2015 © 2014 Statistical Society of Canada Resume L'inference parametrique basee sur la vraisemblance empirique telle que definie par les equations d'estimation de Qin et Lawless (1994) demeure un sujet de recherche actif. Lorsque la taille d’echantillon est faible ou que la dimension des equations d'estimation est elevee, les regions de confiance obtenues presentent souvent un taux de couverture inferieur a leur valeur nominale. De plus, le probleme de l'ensemble vide peut causer des difficultes. La vraisemblance empirique ajustee resout ces deux problemes simultanement. Les regions de confiance decoulant de ces resultats d'ordre superieur necessitent toutefois une estimation precise du niveau d'ajustement requis, ce qui s'avere difficile, surtout dans les cas de surspecification. Dans cet article, les auteurs montrent que la correction de Bartlett peut s'appliquer a la vraisemblance empirique ajustee et proposent une procedure en deux etapes pour la construction de regions de confiance precises. Ils utilisent d'abord une version nai ve de la vraisemblance empirique ajustee pour regler le probleme de l'ensemble vide, puis ils appliquent la correction de Bartlett a l'aide d'une methode de reechantillonnage. Ils illustrent la perfomance de leur methode sur des echantillons finis par des simulations et un exemple. La revue canadienne de statistique 43: 42–59; 2015 © 2014 Societe statistique du Canada