Capture-recapture methodology, originally developed for estimating demographic parameters of animal populations, has been applied to human populations. This tutorial reviews various closed capturerecapture models which are applicable to ascertainment data for estimating the size of a target population based on several incomplete lists of individuals. Most epidemiological approaches merging di erent lists and eliminating duplicate cases are likely to be biased downwards. That is, the ÿnal merged list misses those who are in the population but were not ascertained in any of the lists. If there are no matching errors, then the duplicate information collected from a capture-recapture experiment can be used to estimate the number of missed under proper assumptions. Three approaches and their associated estimation procedures are introduced: ecological models; log-linear models, and the sample coverage approach. Each approach has its unique way of incorporating two types of source dependencies: local (list) dependence and dependence due to heterogeneity. An interactive program, CARE (for capture-recapture) developed by the authors is demonstrated using four real data sets. One set of data deals with infection by the acute hepatitis A virus in an outbreak in Taiwan; the other three sets are ascertainment data on diabetes, spina biÿda and infants' congenital anomaly discussed in the literature. These data sets provide examples to show the usefulness of the capture-recapture method in correcting for under-ascertainment. The limitations of the methodology and some cautionary remarks are also discussed.A. CHAO ET AL. ascertained by three sources: (i) P-list, records based on a serum test taken by the Institute of Preventive Medicine, Department of Health of Taiwan -there were 135 identiÿed cases; (ii) Q-list, local hospital records reported by the National Quarantine Service -122 cases were found; (iii) E-list, records collected by epidemiologiststhere were 126 cases. Merging the three lists by eliminating duplicate records resulted in 271 ascertained cases. This data set has the advantage of a known true number of infected because a screen serological check for all students was conducted after the three surveys. In Section 5, we use this data set to show the need of correction for undercount. 2. Hook et al. [2] and Regal and Hook [3] presented a data set on spina biÿda collected in New York State from 1969-1974. Three lists were collected from birth certiÿcates, death certiÿcates and medical rehabilitation ÿles. There were 513, 207 and 188, cases, respectively, on the three lists and in total 626 ascertained cases. A method of estimating the number of missed cases was discussed by the above authors to assess the completeness of the survey and to accurately estimate the prevalence rate. 3. Bruno et al. [4] collected a data set on diabetes in a community in Italy based on the following four records: diabetic clinic and=or family physician visits (1754 cases); hospital discharges (452 cases); prescriptions (1135 cases), and pu...

Flexible and lightweight graphene nanosheet (GN)/waterborne polyurethane (WPU) composites which exhibit high electrical conductivity and electromagnetic shielding performance were prepared. Covalently modifying GNs with aminoethyl methacrylate (AEMA; AEMA-GNs) through free radical polymerization effectively inhibited the restacking and aggregation of the GNs because of the -NH3(+) functional groups grafted on the AEMA-GNs. Moreover, the AEMA-GNs exhibited high compatibility with a WPU matrix with grafted sulfonated functional groups because of the electrostatic attraction, which caused the AEMA-GNs to homogeneously disperse in the WPU matrix. This homogeneous distribution enabled the GNs to form electrically conductive networks. Furthermore, AEMA-GNs with different amounts of AEMA segments were introduced into the WPU matrix, and the effects of the surface chemistry of the GNs on the electrical conductivity and EMI shielding performance of composites were investigated. AEMA-GN/WPU composites with a GN loading of 5 vol % exhibited remarkable electrical conductivity (approximately 43.64 S/m) and EMI shielding effectiveness (38 dB) over the frequency of 8.2 to 12.4 GHz.

BackgroundTo characterize the clinical and pathological features and survival of patients with human epidermal growth factor receptor 2 (HER2)-low breast cancer in China.MethodsThe China National Cancer Center database was used to identify 1,433 metastatic breast cancer patients with HER2-negative disease diagnosed between 2005 and 2015. Clinicopathological features, survival, and prognosis information were extracted. Overall survival (OS) was estimated using the Kaplan–Meier method and compared using the log-rank test. Prognostic factors associated with OS were analyzed using Cox regression model with 95% confidence interval (95% CI).ResultsThere were 618 (43.1%) and 815 (56.9%) HER2-low and HER2-zero tumors out of 1,433 tumors, respectively. The proportion of hormone receptor (HR)-positive tumors was significantly higher in HER2-low tumors than in those with HER2-zero tumors (77.8% vs. 69.2%, p < 0.001). Patients with HER2-low tumors survived significantly longer than those with HER2-zero tumors in the overall population (48.5 months vs. 43.0 months, p = 0.004) and HR-positive subgroup (54.9 months vs. 48.1 months, p = 0.011), but not in the HR-negative subgroup (29.5 months vs. 29.9 months, p = 0.718). Multivariate regression analysis revealed that HER2-low tumors were independently associated with increased OS in HER2-negative population (HR: 0.85, 95% CI: 0.73–0.98, p = 0.026).ConclusionOur findings demonstrate that HER2-low tumors could be identified as a more distinct clinical entity from HER2-zero tumors, especially for the HR-positive subgroup. A more complex molecular landscape of HER2-low breast cancer might exist, and more precise diagnostic algorithms for HER2 testing could be investigated, thus offering new therapeutic targets for breast cancer treatment.

Our results suggested that pretreatment with i.v. 15 and 30 mg ketorolac reduces pain following propofol injection. Moreover, pretreatment with i.v. ketorolac 10 mg with venous occlusion for 120 s achieves the same pain relief effect.

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After chemical mechanical planarization ͑CMP͒ processes, copper microcorrosion was found in a specific pattern, which consisted of two sides of small trench islands connected by a long underlayer metal line. The depth of the copper recess was strongly dependent on the length of the underlayer metal line as well as the size of the trench islands. This phenomenon was different from typical photocorrosion; it was suggested to be induced by the additional electrochemical potential from the connection of the trench islands. Auger analysis proves that higher copper oxidation rate occurred on the specific pattern compared to those without connection. In addition, the pattern-dependent microcorrosion was identified by blocking the connection of the trench islands. A proposed model was given to account for the enhanced copper corrosion from the specific patterns during CMP.

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