Channels of Interprovincial Consumption Risk Sharing in the People’s Republic of China

This paper analyzes consumption risk sharing among provinces in the People’s Republic of China (PRC) during 1980–2007. The analysis finds that 9.4% of shocks to gross provincial product are smoothed by the interprovincial fiscal transfer system. This system also cushions a relatively large percentage of province-specific shocks in coastal areas. Using a variety of indicators, we explored nonfiscal channels of consumption risk sharing. We found that the migration of rural labor to urban areas and the remittance of migrant wages play an important role in promoting interprovincial consumption risk sharing in inland PRC provinces. In contrast, the extent of risk sharing through financial intermediation and capital markets is very limited. These factors have resulted in a low degree of risk sharing among provinces, especially during the last decade.prc provinces; interprovincial fiscal transfers; consumption risk sharing

Demystifying Event-based Sensor Biasing to Optimize Signal to Noise for Space Domain Awareness

Neuromorphic dynamic vision sensors (DVS), often called event-based sensors (EBS), are a novel class of cameras that have recently shown potential to make a significant impact in the SDA community. Their biologically-inspired design simultaneously achieves high temporal resolution, wide dynamic range, low power consumption and sparse data output, making them an ideal fit for space applications. Although initial results for SDA are promising, they typically exhibit elevated noise rates in dim conditions and have thus far failed to outperform conventional cameras in terms of limiting visual magnitude and sensitivity with high telescope scan rates. A hurdle for widespread adoption is a lack of general guidance regarding optimal camera biases (settings) for SDA. Prior studies either serve as proof of concept or focus on algorithm development; however, to date, none have provided detailed guidance on biasing EBS to optimize signal to noise ratio (SNR) for SDA tasks. The goal of this paper is to narrow the knowledge gap between EBS pixel biasing and resulting performance to optimize their capabilities for SDA. To accomplish this, we adopt a bottom-up approach, revisiting the pixel architecture to consider physics-based performance limitations. In an EBS, each pixel responds autonomously, generating "events" in response to local brightness changes within its field of view (FOV), and outputs a sparse representation of the visual scene where each event is encoded by a pixel address (x,y), a microsecond resolution timestamp (t), and a single bit polarity value (p) indicating either an increase or decrease in brightness by a defined threshold. In most camera models, behavior is fine-tuned by adjusting roughly a half-dozen biases, including threshold levels (sensitivity), bandwidth (speed of the front-end photoreceptor), and refractory period (dead-time between events in a given pixel). These parameters make EBS cameras adaptable for varied applications, but many degrees of freedom presents a challenge for optimization. Researchers unfamiliar with the technology can be overwhelmed by the myriad of biasing options and must either rely on a prescribed set of biases or manually adjust them to achieve desired performance; the latter is not typically recommended for non-experts due to 2nd-order effects such as excessive noise rates. Manufacturer default biases are considered optimized for a broad range of applications, but recent studies have demonstrated non-conventional bias techniques can significantly reduce background noise in dim conditions while still retaining signal, suggesting that SDA capabilities could be improved by a more sophisticated biasing strategy. By conducting a detailed study of how sensitivity, response speed, and noise rates scale with varied bias configurations, we aim to approach an optimal SNR bias configuration and demonstrate the maximal capabilities of current generation COTS EBS cameras for SDA. To systematically analyze and benchmark performance against a calibrated and repeatable stimulus, we developed a custom SDA test-bench to simulate stars/satellites as sub-pixel point source targets of variable speed and brightness. The set-up includes an integrating light box to provide a calibrated flat-field illumination source, a custom 170 mm radius anodized aluminum disk with precision drilled holes of diameters ranging from 100 to 250 microns, and a digitally programmable motor capable of precise speed control from ~0.1 to 800 RPM. The disk is backlit by the flat-field illumination source and connected to the motor shaft, and a 7 x 10 cm region is viewed through a Fujinon 1:1.8/7-70mm CS mount lens at a distance of 50 cm. The FOV and zoom are chosen such that the dimension of the largest holes is still sub-pixel in diameter when in focus. Even with the ability to rapidly collect measurements with this setup, the overall parameter space is still too large to fully explore without any a-priori knowledge about how the sensor responds to signal and noise, and how this depends on biases. As a result, we consider fundamental pixel behaviors to devise an efficient test strategy. We first consider strategies to limit noise rates, as these can overwhelm sensor readout when the background is dark. In prior work, this was presumably accomplished by either reducing the bandwidth biases or increasing threshold biases, but these approaches inherently limit signal. Instead of this naive approach, we draw inspiration from two recent studies: the first demonstrated an optimal balance between two bandwidth related biases accessible in some camera prototypes, and the second relies on a key observation about the statistical distribution of noise events to devise two additional biasing techniques to enhance SNR by allowing either lower thresholds or broader bandwidth settings. Using these techniques as a starting point, we examine the performance the DAVIS346 EBS. We first report baseline performance using manufacturer default biases. To quantify performance, we measure sensitivity (dimmest point source detected) and bandwidth (fastest point source detected). Next, we tune bias settings with specific detection goals (i.e. maximum velocity and/or minimum brightness) and analyze the results. Finally, we apply newly developed low-noise bias techniques and attempt to identify general principles that can be applied universally to any EBS camera to improve performance in SDA tasks. This paper provides a baseline for understanding EBS performance characteristics and will significantly lower the entry barrier for new researchers in the field of event-based SDA. More importantly, it adds insight for optimizing EBS behavior for SDA tasks and demonstrates the absolute performance limits of current generation cameras for detecting calibrated point source targets against a dark background. Finally, this study will enable follow-on work including the development of customized denoising, detection, and tracking algorithms that consider signal response and noise statistics as a function of the selected camera and bias configuration

Differential Prox-1 and CD 31 expression in mucousae, cutaneous and soft tissue vascular lesions and tumors

The study of lymphatic vessels and lymphatic tumors has been hampered with difficulty due to the overlapping morphological features between blood and lymphatic endothelial cells, as well as to the lack of specific lymphatic endothelial markers. Over the last few years, lymphatic vessels and lymphangiogenesis have received great attention owing to their putative implications in terms of metastatic dissemination and the promise of targets for lymphangiogenic therapy. Prox-1 is a nuclear transcription factor that plays a major role during embryonic lymphangiogenesis and is deemed to be a useful marker for differentiating lymphatic endothelial cells from the other blood vessels endothelial cells. Here, we describe a double-immunostaining strategy for formalin-fixed, paraffinembedded tissues that aims at evaluating the distribution of Prox-1 and CD 31 – a cytoplasmic pan-endothelial marker -in a series of 28 mucousae, cutaneous and soft tissue vascular lesions and tumors, including hemangiomas, lymphangiomas, lymphangiectasia, and Kaposi’s sarcomas. Our results showed that in non-lesional mucousae and skin, Prox-1 decorated exclusively the nuclei of endothelial cells in lymphatic vessels. Prox-1 stained almost all the benign lymphatic vascular lesions/tumors (91%) and was absent or only focally positive in 75% of blood vascular tumors. CD 31 stained endothelial cells of blood vessels of superficial and deep dermal plexuses, lymphatics, and all blood vascular lesions/tumors. Kaposi’s sarcomas were all positive for both CD 31 and Prox-1 markers. In conclusion, although Prox-1 expression in vascular lesions/tumors was not entirely restricted to tumors with known lymphatic differentiation, CD 31/Prox-1 double-immunolabeling can be used as an adjunct marker to identify lymphatic vessels in routinely processed formalin-fixed, paraffin-embedded samples

Justifying top management pay in a transitional economy

We investigate some aspects of top management pay in China\u27s listed firms. We find positive pay and performance sensitivities and elasticities for top executives. In terms of magnitude, these sensitivities are similar to those reported in U.S. firms during the 1970s. However, the pay and performance relation is slightly weaker for firms located in less developed provinces. We also find that the pay disparities between top managers and employees are positively related to a firm\u27s performance. Thus, it appears that any deviation away from a manager-worker compensation norm has to be justified by superior firm performance. In additional analyses, we find that managers\u27 perquisites are not related to performance

Positive wellbeing and resilience following adolescent victimisation: An exploration into protective factors across development

Background Not all victims of bullying go on to develop problems with their mental health. To understand factors that may confer resilience, many have explored the moderating role of protective factors in relation to mental illness. No study to date, however, has considered moderators of adult wellbeing following victimisation. We explore 14 protective factors and test whether these promote good adult wellbeing in addition to prevent mental illness following victimisation. In doing so, we aimed to understand how positive mental health and resilience can be promoted. Methods Data were derived from the Avon Longitudinal Study of Parents and Children. Participants were assessed for wellbeing and depressive symptoms at age 23, as well as victimisation in adolescence, and protective factors across development. Protective factors were categorised into individual-, family- and peer-level, and included factors like social skills, perceived school competence, and relationships with family and peers. The moderating role of the protective factors were examined using interactive regression models. Results Perceived scholastic competence was the only factor that mitigated some of the negative effects of victimisation. Individuals with higher perceptions of scholastic competence had higher wellbeing in adulthood than victims with lower perceptions of competence. No protective factors positively moderated life satisfaction or the risk of depressive symptoms; although findings suggest that friendships in late adolescence may be protective for individuals exposed to less frequent victimisation. Conclusions Our study is the first to explore a wide range of protective factors in predicting adult wellbeing following victimisation. We identify factors involved specifically in supporting wellbeing but not in reducing the risk of depression. Findings suggest that interventions aimed at increasing perceptions of scholastic competence in childhood may help to support more positive wellbeing in adulthood

The biological carbon pump in CMIP6 models: 21st century trends and uncertainties

The biological carbon pump (BCP) stores ∼1,700 Pg C from the atmosphere in the ocean interior, but the magnitude and direction of future changes in carbon sequestration by the BCP are uncertain. We quantify global trends in export production, sinking organic carbon fluxes, and sequestered carbon in the latest Coupled Model Intercomparison Project Phase 6 (CMIP6) future projections, finding a consistent 19 to 48 Pg C increase in carbon sequestration over the 21st century for the SSP3-7.0 scenario, equivalent to 5 to 17% of the total increase of carbon in the ocean by 2100. This is in contrast to a global decrease in export production of –0.15 to –1.44 Pg C y–1. However, there is significant uncertainty in the modeled future fluxes of organic carbon to the deep ocean associated with a range of different processes resolved across models. We demonstrate that organic carbon fluxes at 1,000 m are a good predictor of long-term carbon sequestration and suggest this is an important metric of the BCP that should be prioritized in future model studies

Discovery and Follow-up Observations of the Young Type Ia Supernova 2016coj

The Type~Ia supernova (SN~Ia) 2016coj in NGC 4125 (redshift $z=0.004523$) was discovered by the Lick Observatory Supernova Search 4.9 days after the fitted first-light time (FFLT; 11.1 days before $B$-band maximum). Our first detection (pre-discovery) is merely $0.6\pm0.5$ day after the FFLT, making SN 2016coj one of the earliest known detections of a SN Ia. A spectrum was taken only 3.7 hr after discovery (5.0 days after the FFLT) and classified as a normal SN Ia. We performed high-quality photometry, low- and high-resolution spectroscopy, and spectropolarimetry, finding that SN 2016coj is a spectroscopically normal SN Ia, but with a high velocity of \ion{Si}{2} $\lambda$6355 ($\sim 12,600$\,\kms\ around peak brightness). The \ion{Si}{2} $\lambda$6355 velocity evolution can be well fit by a broken-power-law function for up to a month after the FFLT. SN 2016coj has a normal peak luminosity ($M_B \approx -18.9 \pm 0.2$ mag), and it reaches a $B$-band maximum \about16.0~d after the FFLT. We estimate there to be low host-galaxy extinction based on the absence of Na~I~D absorption lines in our low- and high-resolution spectra. The spectropolarimetric data exhibit weak polarization in the continuum, but the \ion{Si}{2} line polarization is quite strong ($\sim 0.9\% \pm 0.1\%$) at peak brightness.Comment: Submitte