Hydrological variations in central China over the past millennium and their links to the Tropic Pacific and North Atlantic Oceans

Variations of precipitation, aka the Meiyu rain, in East Asian summer monsoon (EASM) domain during the last millennium could help enlighten the hydrological response to future global warming. Here we present a precisely dated and highly resolved stalagmite δ18O record from the Yongxing Cave, central China. Our new record, combined with a previously published one from the same cave, indicates that the Meiyu rain has changed dramatically in association with the global temperature change. In particular, our record shows that the Meiyu rain has been weakened during the Medieval Climate Anomaly (MCA), but intensified during the Little Ice Age (LIA). During the Current Warm Period (CWP), our record indicates a similar weakening of the Meiyu rain. Furthermore, during the MCA and CWP, our records show that the atmospheric precipitation is similarly wet in northern China and similarly dry in central China, but relatively wet during the CWP in southern China. This spatial discrepancy indicates a complicated localized response of the regional precipitation to the anthropogenic forcing. The weakened (intensified) Meiyu rain during the MCA (LIA) matches well with the warm (cold) phases of Northern Hemisphere surface air temperature. This Meiyu rain pattern also corresponds well with the climatic conditions over the Tropical Indo-Pacific warm pool. On the other hand, our record shows a strong association with the North Atlantic climate as well. The reduced (increased) Meiyu rain correlates well with positive (negative) phases of North Atlantic Oscillation. In addition, our record links well with the strong (weak) Atlantic meridional overturning circulation during the MCA (LIA) period. All above-mentioned localized correspondences and remote teleconnections on decadal to centennial timescales indicate that the Meiyu rain is coupled closely with oceanic processes in the Tropical Pacific and North Atlantic Oceans during the MCA and LIA

Benchmark dose modeling for epidemiological dose-response assessment using prospective cohort studies

Benchmark dose (BMD) methodology has been employed as a default dose-response modeling approach to determine the toxicity value of chemicals to support regulatory chemical risk assessment. Especially, a relatively standardized BMD analysis framework has been established for modeling toxicological data regarding the formats of input data, dose-response models, definitions of benchmark response, and model uncertainty consideration. However, the BMD approach has not been well developed for epidemiological data mainly because of the diverse designs of epidemiological studies and various formats of data reported in the literature. Although most of the epidemiological BMD analyses were developed to solve a particular question, the methods proposed in two recent studies are able to handle cohort and case-control studies using summary data with consideration of adjustments for confounders. Therefore, the purpose of the present study is to investigate and compare the "effective count"-based BMD modeling approach and adjusted relative risk (RR)-based BMD analysis approach to identify an appropriate BMD modeling framework that can be generalized for analyzing published data of prospective cohort studies for BMD analysis. The two methods were applied to the same set of studies that investigated the association between bladder and lung cancer and inorganic arsenic exposure for BMD estimation. The results suggest that estimated BMDs and BMDLs are relatively consistent; however, with the consideration of established common practice in BMD analysis, modeling adjusted RR values as continuous data for BMD estimation is a more generalizable approach harmonized with the BMD approach using toxicological data

State of Philanthropy Among Asian Americans and Pacific Islanders: Findings and Recommendations to Strengthen Visibility and Impact

Asian Americans and Pacific Islanders (AAPIs) have been an important part of the United States for over 170 years, and are the fastest-growing racial groups in the country today. AAPIs have made significant gains in political representation, from the halls of Congress to state and local offices. We have also seen important gains in understanding the demographic makeup and public opinion of Asian Americans and Pacific Islanders.Yet, when it comes to philanthropy, AAPIs continue to be rendered invisible and marginal. This report—based on a summary of prior findings and insights from several data collections, including prior population surveys, content analysis of philanthropy news coverage, and surveys and interviews of leaders and staff in philanthropy—indicates that grantmaking to AAPIs remains a relatively low priority, and that AAPIs continue to face barriers when it comes to serving in leadership roles

Acute and contained rupture of the descending thoracic aorta: Treatment with endovascular stent grafts

AbstractPurpose: The purpose of this study was to evaluate feasibility and safety of endovascular stent grafting for the treatment of patients with rupture of the descending thoracic aorta. Methods: Thirteen patients with rupture of the descending thoracic aorta were treated with endovascular stent grafting. Six patients were treated on the day of diagnosis because their vital signs were unstable, and the other seven patients were treated electively. Five patients had infection or potential infection, and the other eight patients did not. Expanded polytetrafluoroethylene-covered or polyester-covered Z stents were used in all patients. Results: Stent grafts were successfully placed in all patients. No endoleaks were observed at the end of the procedure. However, rebleeding was observed within 2 weeks of the procedure in two patients with infection. Six patients (46%) died within 5 months of the procedure (mean survival period, 61 ± 60 days). All five patients with infection (100%) died, and only one of eight patients without infection (13%) died (P <.01). The remaining seven patients are alive during the mean follow-up period of 21 months (overall survival rate, 54%), although additional surgical interventions, including surgical conversion in one case and upper extremity extraanatomic bypass in the other, were necessary in two of these patients. Conclusion: Endovascular stent grafting may be a safe and feasible method for the treatment of rupture of the descending thoracic aorta in selected patients without infection. However, its usefulness in terms of long-term prognosis appears to be extremely limited, especially in patients with infection. (J Vasc Surg 2003;37:100-5.

Variations in the East Asian summer monsoon over the past 1 millennium and their links to the Tropic Pacific and North 2 Atlantic oceans

Variations of East Asian summer monsoon (EASM) during the last millennium could help enlighten the monsoonal response to future global warming. Here we present a precisely dated and highly resolved stalagmite δ18O record from the Yongxing Cave, central China. Our new record, combined with a previously published one from the same cave, indicates that the EASM has changed dramatically in association with the global temperature rising. In particular, our record shows that the EASM has intensified during the Medieval Climate Anomaly (MCA) and the Current Warm Period (CWP) but weakened during the Little Ice Age (LIA). We find that the EASM intensity is similar during the MCA and CWP periods in both northern and central China, but relatively stronger during the CWP in southern China. This discrepancy indicates a complicated regional response of the EASM to the anthropogenic forcing. The intensified and weakened EASM during the MCA and LIA matches well with the warm and cold phases of Northern Hemisphere surface air temperature, respectively. This EASM pattern also corresponds well with the rainfall over the tropical Indo-Pacific warm pool. Surprisingly, our record shows a strong association with the North Atlantic climate as well. The intensified (weakened) EASM correlates well with positive (negative) phases of North Atlantic Oscillation. In addition, our record links well with the strong (weak) Atlantic meridional overturning circulation during the MCA (LIA) period. All above-mentioned correlations indicate that the EASM tightly couples with oceanic processes in the tropical Pacific and North Atlantic oceans during the MCA and LIA

Coevolutionary particle swarm optimization using AIS and its application in multiparameter estimation of PMSM

In this paper, a coevolutionary particle-swarm-optimization (PSO) algorithm associating with the artificial immune principle is proposed. In the proposed algorithm, the whole population is divided into two kinds of subpopulations consisting of one elite subpopulation and several normal subpopulations. The best individual of each normal subpopulation will be memorized into the elite subpopulation during the evolution process. A hybrid method, which creates new individuals by using three different operators, is presented to ensure the diversity of all the subpopulations. Furthermore, a simple adaptive wavelet learning operator is utilized for accelerating the convergence speed of the pbest particles. The improved immune-clonal-selection operator is employed for optimizing the elite subpopulation, while the migration scheme is employed for the information exchange between elite subpopulation and normal subpopulations. The performance of the proposed algorithm is verified by testing on a suite of standard benchmark functions, which shows faster convergence and global search ability. Its performance is further evaluated by its application to multiparameter estimation of permanent-magnet synchronous machines, which shows that its performance significantly outperforms existing PSOs. The proposed algorithm can estimate the machine dq-axis inductances, stator winding resistance, and rotor flux linkage simultaneously. © 2013 IEEE