Is Earnings Uncertainty Relevant for Educational Choice? An Empirical Analysis for China

We use the method of Dominitz and Manski (1996) to solicit anticipated wage distributions for continuing to a Master degree or going to work after completing the Bachelor degree. The means of the distributions have an effect on intention to continue as predicted by theory. The dispersions in these individual distributions have no effect on intention to continue, suggesting that anticipated earnings risk does not play a role in the decision.educational choice, wage expectations

Selfish and Altruistic Bacterial Populations Maximize Fitness Under Stress by Local Segregation

Landscapes in ecology have a profound influence on the adaption and evolution of competing populations for resources. We are interested in how altruistic populations survive in the presence of selfish individuals in a non-stirred, closed and complex nutrient landscape. Well-stirred (landscape-free) but closed environments have a depressing future when selfish individuals arise in a population, a fate known as the tragedy of the Commons. Over-exploitation of a well-stirred communal habitat by selfish individuals which do not follow rules of communal self-regulation ends up in the elimination (extinction) of both the original altruistic inhabitants and the selfish population. In the context of bacterial population, the Commons tragedy that occurs is the consumption of limited resources by the individuals, resulting in metabolic stressing of the bacteria and growth advantages to be gained by defection from a ``social contract" of altruistic cooperation. There is no avoidance of this tragedy and the collapse of an original altruistic wild-type population by an emergent selfish population in a well-stirred but closed environment is inevitable. However, there is a fundamental difference between resource exploitation in a well-stirred homogenous commons and in a heterogenous landscape of nutrients which is not stirred. We show here using a non-stirred nanofabricated habitat landscape that altruists and selfish bacteria can in fact coexist, that they can maintain phenotype diversity and avoid the tragedy of the Commons. This emergent spatial segregation of competing populations under stress greatly changes, we believe, our perception of the true sophistication of bacterial response to stress and competition, and has broad implications for the adaptive strategies of higher organisms under stress in complex environments

Process and Kinetic Mechanism of Elimination of Chlorine Combined in Molecule of Bleached Shellac

Purpose: To investigate the process and kinetics of the removal of chlorine integrated in a molecule of bleached shellac applied as pharmaceutical excipient.Methods: Sodium ethoxide was employed to react selectively with the carbon atom connecting with chlorine, which induced the removal of chlorine by means of elimination reaction. The technologic parameters, such as dosage of sodium ethoxide, temperature, time, etc, influencing dechlorination efficiency were studied. Furthermore, the kinetics of chlorine removal was investigated by analyzing the variation of chlorine content with time and temperature.Results: The results demonstrate that the optimal conditions for eliminating combined chlorine are to react with 3.15 g of sodium ethoxide at 90 oC for 90 min. Under the optimal conditions, the content of chlorine in the final products is 0.28 % w/w, which is far smaller than that in the products prepared without dechlorination (2.6 % w/w)..Conclusion: Combined chlorine, which is harmful to the properties of shellac, can be removed in the presence of sodium ethoxide by means of elimination, and the reaction for chlorine content of shellac is first order reaction.Keywords: Enteric coating, Sustained release, Elimination method, Nucleophile, Shellac, Natural product

Twist Springback of Asymmetric Thin-walled Tube in Mandrel Rotary Draw Bending Process

AbstractThis paper aims to develop an effective numerical model and analyse the twist springback behaviour of asymmetric thin-walled tube in mandrel rotary draw bending. Yld2000-2d anisotropic yield criterion integrated with mixed isotropic and kinematic hardening model was used to describe the material properties including anisotropy and Bauschinger effect. The corresponding mechanical experiments such as uniaxial tension, monotonic and forward-reverse shear tests were performed to obtain the material parameters. A three-dimensional elastic-plastic finite element model was developed, and its validity was assessed by comparing the predicted twist springback with experiment one. Based on the present FE model, the tangential stress distribution during different bending steps were analysed to explore the source of twist springback. The results indicate that the torsion moment of cross sections caused by the non-homogenous stress states play a considerable role in twist springback prediction

Dominant channels of exciton spin relaxation in photoexcited self-assembled (In,Ga)As quantum dots

We present a comprehensive theoretical investigation of spin relaxation processes of excitons in photoexcited self-assembled quantum dots. The exciton spin relaxations are considered between dark- and bright-exciton states via the channels created by various spin-admixture mechanisms, including electron Rashba and Dresselhaus spin- orbital couplings (SOCs), hole linear and hole cubic SOCs, and electron hyperfine interactions, incorporated with single- and double-phonon processes. The hole-Dresselhaus SOC is identified as the dominant spin-admixture mechanism, leading to relaxation rates as fast as ∼10−2 ns−1, consistent with recent observations. Moreover, due to significant electron-hole exchange interactions, single-phonon processes are unusually dominant over two-phonon ones in a photoexcited dot even at temperatures as high as 15 K

中药泡洗改善肿瘤患者生活质量临床观察

Objective: To evaluate the effects of the traditional Chinese medicine (TCM) soaking on the quality of life for advanced cancer patients. Methods: With a prospective, longitudinal cohort study, based on patient’s Compliance, 96 cancer patients admitted to Xiyuan Hospital were allocated in the study, 94 cases evaluated at last: the experiment group (65cases), the control group (29cases). Patients in the experiment group accepted TCM soaking, the patients in the control group just accepted the conventional treatment without any TCM soaking. A course of treatment was two weeks, with 35 minutes each day, 5 days a week. The Quality of Life (QOL)，Karnofsky performance score (KPS) and Levis of neurotoxicity were measured in the two groups pro-post treatment respectively. Results: There were no significant differences for some items in baseline at comparable scales in the two groups (P > 0.05). There were significant differences in symptoms, KPS and Levis score in experiment group. Additionally, there were significant differences in symptoms and Levis score (P < 0.05), however, no significant differences in KPS when comparing two groups (P > 0.05). Conclusion: TCM socking has a curative effect in relieving symptoms for advanced cancer patients 目的  探讨中药泡洗改善肿瘤患者生活质量的临床疗效。方法  96例住院肿瘤患者，根据患者顺应性分组队列观察，可评价94例，治疗组用中药泡洗治疗，对照组常规抗肿瘤治疗，观察两组主观症状评分，生活质量，神经毒性发生率。结果  两组治疗前各主观症状评分变化比较，无统计学差异（P > 0.05），具有可比性。经过干预2周后，治疗组组内比较：患者的主观症状评分和Levis评分，干预后较干预前差异具有统计学意义（P < 0.05）。经过2周中药泡洗干预后，两组比较，治疗组的Levis评分、主观症状评分中好于对照组，但是KPS无统计学差异（P > 0.05）。结论  中药泡洗可改善肿瘤患者的主观症状，改善患者的健康状况及生活自理能力，提高肿瘤患者的生活质量

Urban–rural difference in the costs of disability and its effects on poverty among people with disabilities in China

The urban–rural difference in poverty is an important issue in China, particularly for people with disabilities. The extra costs of disability render this population susceptible to falling into poverty, where this can exacerbate the inequality among people with disabilities between urban and rural areas of the country. Previous studies have provided empirical evidence for the extra costs of disabilities in certain countries, but little scholarly attention has been devoted to the urban–rural gap in the costs of disability, particularly in countries like China that have a dual urban–rural system. This study explores changes in the extra costs of disability in China between urban and rural households with disabled members from 2008 to 2018 by using the standard of living approach. We apply the Foster–Greer–Thorbecke Poverty Index to measure the rates of poverty in urban and rural households with disabilities after considering the costs of disability. The results reveal that the costs of disability were not always lower for rural households than for urban households. At the same time, many rural households with disabled people were found to suffer from severe poverty owing to the high costs of their disabilities. The difference in health insurance and rehabilitation services between urban and rural China have led to an urban-rural gap in the costs of disability. This suggests that supplying more goods and services for disabled people in rural areas, especially free services, and raising the reimbursement due to them from their health insurance can help improve their standard of living

Pre-strain effect on twist springback of a 3D P-channel in deep drawing

With the widely use of high-strength steel sheets in the automotive industry, the twist springback phenomenon of the steel sheets under multi-step forming conditions has received extensive attention. In this work, the Dual Phase steel DP500 is taken as the research object to investigate the complex non-linear elastoplastic behaviors and twist springback under two-step loading paths. The large specimen with a pre-strain of 4% true strain in rolling direction is carried out on a large tensile testing machine, and several specific blanks are extracted from it at different directions for a subsequent P-channel forming. The influence of twist springback associated with the pre-strain is analyzed. The finite element model based on the non-linear elastic model and the homogeneous anisotropic hardening model (HAH) is also established for the springback prediction and stress analysis. The results indicate that the pre-strain has a considerable impact on the twist springback. The non-linear strain path changes resulted from pre-straining not only influence the residual stress but also affect the elastic modulus distribution.publishe

Genome-scale MicroRNA target prediction through clustering with Dirichlet process mixture model

Background: MicroRNA regulation is fundamentally responsible for fine-tuning the whole gene network in human and has been implicated in most physiological and pathological conditions. Studying regulatory impact of microRNA on various cellular and disease processes has resulted in numerous computational tools that investigate microRNA-mRNA interactions through the prediction of static binding site highly dependent on sequence pairing. However, what hindered the practical use of such target prediction is the interplay between competing and cooperative microRNA binding that complicates the whole regulatory process exceptionally. Results: We developed a new method for improved microRNA target prediction based on Dirichlet Process Gaussian Mixture Model (DPGMM) using a large collection of molecular features associated with microRNA, mRNA, and the interaction sites. Multiple validations based on microRNA-mRNA interactions reported in recent large-scale sequencing analyses and a screening test on the entire human transcriptome show that our model outperformed several state-of-the-art tools in terms of promising predictive power on binding sites specific to transcript isoforms with reduced false positive prediction. Last, we illustrated the use of predicted targets in constructing conditional microRNA-mediated gene regulation networks in human cancer. Conclusion: The probability-based binding site prediction provides not only a useful tool for differentiating microRNA targets according to the estimated binding potential but also a capability highly important for exploring dynamic regulation where binding competition is involved