Identifying the twist factor of twisted partially coherent optical beams.

Twisted partially coherent light, characterized by its unique twist factor, offers novel control over the statistical properties of random light. However, the recognition of the twist factor remains a challenge due to the low coherence and the stochastic nature of the optical beam. This paper introduces a method for the recognition of twisted partially coherent beams by utilizing a circular aperture at the source plane. This aperture produces a characteristic hollow intensity structure due to the twist phase. A deep learning model is then trained to identify the twist factor of these beams based on this signature. The model, while simple in structure, effectively eliminates the need for complex optimization layers, streamlining the recognition process. This approach offers a promising solution for enhancing the detection of twisted light and paves the way for future research in this field.

[Indicator Function of Ragworm (Nereididae) on Sediment Microplastic in Haizhou Bay Intertidal Zone].

Sediment samples were collected from nine sites of three sections, in the intertidal zone of Haizhou bay in July 2018. The abundance and characteristics of microplastics in the sediments (and ragworms within the sediments) were then determined to identify the source of microplastics in ragworms, and to explore the effects of ragworms on microplastics in sediment. The average abundance of microplastics in tidal flat sediments was (0.49±0.17) n·g-1, which was at a high level in domestic offshore environmental studies. Among all the microplastics detected, the most common form and color were fiber and black-gray, respectively, and the materials were mainly polyethylene (PE), polyester (PET), and polystyrene (PS). The detection rate of microplastics in ragworm was 77.78%-86.67%, with an average abundance of (6.68±2.21) n·ind-1; the abundance was significantly correlated with individual mass (r=0.42, P=0.002). The microplastic abundance was significantly higher in ragworms with individual mass over 1.5 g than in those with a mass of<0.5 g or 0.5-1 g (F3=141.029, P=0.000). In ragworms, microplastics were dominated by small black or blue fibers, and the main materials were PE and PET. By analyzing the various characteristics of microplastics with a particle size of 0-3 mm, it was found that the abundance of microplastics in sediments was strongly correlated with that in ragworms (r=0.79,P=0.01); the main form (r=0.90, P=0.035) and the material composition (r=0.73, P=0.024) also showed significant correlation between sediments and ragworms. This indicates that ragworms ingest microplastics in the sedimentary environment and exchange the microplastics with the sediments. Therefore, ragworms can be used as an indicator species of microplastic pollution in sediments.

Temporal Dynamics of the Interaction between Reward and Time Delay during Intertemporal Choice.

Intertemporal choice involves the processes of valuation and choice. Choice is often the result of subjective valuation, in which reward is integrated with time delay. Here, using event-related potential (ERP) signals as temporal hallmarks, we aim to investigate temporal dynamics of how reward interacts with time delay during a delayed discounting task. We found that participants preferred immediate rewards when delayed rewards were small or over long-term delays. Our ERP results suggested that the P200 component reflected an initial valuation of reward and time delay, while the frontal N2 component correlated with individual choices of immediate option of rewards. The LPP component was modulated by the N2 component. These findings demonstrate that the N2 component is the key component in temporal dynamics of the interaction between reward and time valuation.

Town mouse or country mouse: identifying a town dislocation effect in Chinese urbanization.

Understanding urbanization and evaluating its impact are vital for formulating global sustainable development. The results obtained from evaluating the impact of urbanization, however, depend on the kind of measurement used. With the goal of increasing our understanding of the impact of urbanization, we developed direct and indirect subjective indicators to measure how people assess their living situation. The survey revealed that the projected endorsements and perceived social ambiance of people toward living in different types of settlements did not improve along with the urbanization level in China. The assessment scores from the city dwellers were not significantly different from those from the country areas and, more surprisingly, both were significantly higher than the assessment scores of the town dwellers, which we had expected to fall between the assessment scores of the country and city dwellers. Instead their scores were the lowest. We dubbed this V-shaped relationship the "town dislocation effect." When searching for a potential explanation for this effect, we found additional town dislocation effects in social support, loss aversion, and receptivity toward genetically modified food. Further analysis showed that only social support mediated the relationship between the three tiers of settlements (cities, country areas, and towns) and the subjective indicator. The projected endorsements yielded significant subjective assessments that could enhance our understanding of Chinese urbanization. Towns posed specific problems that require special attention.

Victims' time discounting 2.5 years after the Wenchuan earthquake: an ERP study.

BACKGROUND: Time discounting refers to the fact that the subjective value of a reward decreases as the delay until its occurrence increases. The present study investigated how time discounting has been affected in survivors of the magnitude-8.0 Wenchuan earthquake that occurred in China in 2008. METHODOLOGY: Nineteen earthquake survivors and 22 controls, all school teachers, participated in the study. Event-related brain potentials (ERPs) for time discounting tasks involving gains and losses were acquired in both the victims and controls. FINDINGS: The behavioral data replicated our previous findings that delayed gains were discounted more steeply after a disaster. ERP results revealed that the P200 and P300 amplitudes were increased in earthquake survivors. There was a significant group (earthquake vs. non-earthquake) × task (gain vs. loss) interaction for the N300 amplitude, with a marginally significantly reduced N300 for gain tasks in the experimental group, which may suggest a deficiency in inhibitory control for gains among victims. CONCLUSIONS: The results suggest that post-disaster decisions might involve more emotional (System 1) and less rational thinking (System 2) in terms of a dual-process model of decision making. The implications for post-disaster intervention and management are also discussed.

Progression of the "Psychological Typhoon Eye" and variations since the Wenchuan earthquake.

BACKGROUND: In 2008 after a massive earthquake jolted Wenchuan, China, we reported an effect that we termed a "Psychological Typhoon Eye": the closer to the center of the devastated area, the lower the level of concern felt by residents about safety and health. We now report on the progression of this effect and the development of new variations after the quake as well as investigating potential explanations. METHODOLOGY/PRINCIPAL FINDINGS: We conducted two sequential surveys of 5,216 residents in non-devastated and devastated areas in September-October 2008 and April-May 2009. Respondents were asked five questions to assess their concerns about safety and health. A MANCOVA showed a significant inverse effect of residential devastation level on the estimated number of medical and psychological workers needed, the estimated probability of an epidemic outbreak, and the estimated number of self-protective behaviors needed (Ps<0.001), in spite of the passage of one year. The level of post-earthquake concern decreased significantly with an increase in the residential devastation level. Additionally, we observed two variations in the "Psychological Typhoon Eye" effect, in that the respondents' concern decreased with increasing relational distance between a respondent and victims who had suffered either physical or economic damage. CONCLUSIONS/SIGNIFICANCE: The previously reported effect of a "Psychological Typhoon Eye" remains robust over a 1-year period. We found that the "psychological immunization" theory did not provide a satisfactory explanation for these intriguing results. Our findings may be useful in understanding how people become resilient to threats.

Can overconfidence be debiased by low-probability/high-consequence events?

During the first half of 2008, China suffered three natural disasters: a heavy snow storm, an outbreak of hand-foot-mouth disease, and a severe earthquake. The aim of the present study is to explore how low-probability/high-consequence events influence overconfidence. In Study 1, opportunity samples were obtained by recruiting residents in three different types of disaster-hit areas to answer a peer-comparison probability judgment questionnaire about 1 month after the corresponding disaster occurred. The performance of 539 participants in disaster-hit areas was compared with that of 142 residents in a nondisaster area. The findings indicate that residents in disaster-hit areas were less overconfident than those in the nondisaster area on both positive and negative events. In Study 2, we surveyed a total of 336 quake-victims 4 and 11 months after the earthquake to examine whether the impact of disasters on overconfidence would decay with time. The resulting data indicate that the disaster victims became more overconfident as time elapsed. The overall findings suggest that low-probability/high-consequence events could make people less overconfident and more rational and seem to serve as a function of debiasing.

Psychological typhoon eye in the 2008 Wenchuan earthquake.

BACKGROUND: On May 12, 2008, an earthquake measuring 8.0 on the Richter scale jolted Wenchuan, China, leading to 69,227 deaths and 374,643 injured, with 17,923 listed as missing as of Sept. 25, 2008, and shook the whole nation. We assessed the devastating effects on people's post-earthquake concern about safety and health. METHODOLOGY/PRINCIPAL FINDINGS: From June 4 to July 15, 2008, we surveyed a convenience sample of 2,262 adults on their post-earthquake concern about safety and health. Residents in non-devastated areas (Fujian and Hunan Provinces, and Beijing) and devastated areas (Sichuan and Gansu Provinces) responded to a questionnaire of 5 questions regarding safety measures, epidemic disease, medical workers, psychological workers, and medication. The ANOVAs showed a significant effect of residential devastation level on the estimated number of safety measures needed, the estimated probability of the outbreak of an epidemic, and the estimated number of medical and psychological workers needed (Ps<0.001). The post-earthquake concern decreased significantly as the level of residential devastation increased. Because of the similarity with the meteorological phenomenon of the eye of a typhoon, we dubbed these findings a "Psychological Typhoon Eye": the closer to the center of the devastated areas, the less the concern about safety and health a resident felt. CONCLUSIONS/SIGNIFICANCE: Contrary to common perception and ripple effect that the impact of an unfortunate event decays gradually as ripples spread outward from a center, a "Psychological Typhoon Eye" effect was observed where the post-earthquake concern was at its lowest level in the extremely devastated areas. The resultant findings may have implications for Chinese governmental strategies for putting "psychological comfort" into effect.