Abstract

Purpose – Investigation of the anomalies associated with crashes and jackpots in the Chinese stock market.

Design/methodology/approach – We propose a logit model to predict the events of crashes and jackpots in the Chinese stock market. The model introduces a new variable of the price-to-sales ratio and takes into account the market states, Up and Down.

Findings – The anomalies associated with crashes and jackpots are not related to variations in economic conditions, but are associated with limits to arbitrage. High-liquidity stocks have strong mispricing effects. The institutions’ speculative trading will push liquid stock prices further away from their fundamentals but avoid buying illiquid stocks with a higher probability of price crashes and jackpots.

Originality/value – We propose a logit model to predict the extreme events of both crash and jackpot in the Chinese stock market. Our model effectively disentangles from CRASHP and JACKP. Compared with the traditional model, it substantially enhances in-sample and out-sample predictions. Based on the predictions of the extreme events, we find two strong and robust pricing effects associated with ex ante CRASH and JACKP in the Chinese stock market.

As intrinsically carbon-free molecules, ammonia and hydrogen are considered as fuels for internal combustion engines, mainly for long-distance or off-road applications. These alternative fuels have different combustion characteristics, reactivity, and exhaust gas compositions compared to conventional fuels, raising questions about the suitability of lubricants in engines operating with them. The impact of ammonia, hydrogen, and their blends on lubricants in internal combustion engines is a relatively new topic, with few reference studies available. However, degradation processes of lubricants have been studied in the context of hydrocarbon fuels, and in compressors using ammonia as a refrigerant, for example. This work presents a review of the literature on engine oil degradation phenomena in relation to ammonia and hydrogen combustion characteristics. In particular, it highlights the current state of knowledge regarding compatibility with unburnt gases, elevated nitrogen oxide levels, and water. Additionally, it summarizes the latest insights into the contribution of lubricants to pollutant emissions.

Lead-acid batteries are indispensable in various applications, and it is crucial to monitor their status. However, the existing sensing units for lead-acid batteries are limited by their bulky size, slow response time, and lack of temperature sensing and compensation capabilities. In the current work, a compact GaN-based sensing device was proposed to simultaneously measure the electrolyte density and temperature. The device comprises a light-emitting diode (LED) and a photodetector (PD) integrated on a GaN-on-sapphire chip in a monolithic configuration. The forward voltage of the LED reflects the electrolyte temperature, while the photocurrent of the PD varies with electrolyte density due to optical reflection changes at the exposed sapphire interface. The measured signals were processed using a decoupling matrix to achieve temperature compensation. The device exhibits a sensitivity of −29.1 μA/(g/cm³) for density in the range of 1.09 g/cm³ to 1.29 g/cm³, and -1.07 mV/°C for temperature in the range of 25 to 45 °C. The performance of the device was also validated through comparisons with commercial meters and real-time monitoring during the charging and discharging of the batteries. The device has notable advantages in size, cost, and fast response/recovery time (134.3/201.4 ms), rendering it a promising tool for monitoring lead-acid batteries.

A new study has identified a key enzyme that modulates tea plant immunity by regulating salicylic acid (SA), a critical plant defense hormone. The enzyme, CsUGT74B5, catalyzes the conversion of SA into a glucosylated form, salicylic acid 2-O-β-D-glucoside (SAG). This process reduces free SA levels, diminishing the plant’s resistance to anthracnose—a devastating fungal disease affecting tea crops worldwide. Experimental evidence showed that overexpressing CsUGT74B5 in tea leaves and model plants increased disease susceptibility, while applying SA externally enhanced pathogen defense. The findings reveal a previously unknown glucosylation mechanism that fine-tunes immune balance in tea plants.

Cold stress severely limits grapevine survival and fruit production. In this study, scientists discovered that the transcription factor VaWRKY65 plays a pivotal role in helping Vitis amurensis withstand freezing temperatures. The gene enhances cold tolerance through a dual mechanism: promoting the breakdown of starch into soluble sugars and stimulating the detoxification of reactive oxygen species (ROS). These combined effects improve cellular stability and energy balance under stress. The research also identified VaBAM3 and VaPOD36 as key downstream genes activated by VaWRKY65. This work uncovers how sugar metabolism and ROS scavenging are transcriptionally coordinated to strengthen cold resilience in grapevine.

The coupled effect of dynamics and nucleation during supercooled droplet’s collision on superhydrophobic surface plays an important role in the anti-icing capability of different superhydrophobic surface, however, without any method to evaluate it. In this work, the impact-freezing behaviors of supercooled droplets on surfaces with different wettability, including two typical hydrophobic surfaces, were investigated experimentally. The morphology, size, velocity, and nucleation rate of freezing on each surface at different temperatures were extracted, based on which emphasis was put on discussing the discrepancy of freezing processes and the formation mechanism of freezing morphologies on different superhydrophobic surfaces. The main findings are: (1) The freezing morphology on superhydrophobic surface was independent of contact angle and supercooling degree, but depended on the surface roughness; (2) the interaction between the fast motion of unfrozen water and the generation of ice nucleus dominates in the formation of freezing morphology, while the ice growth process has less influence. On smooth surface, multiple ice nucleus generating before bounce impeded the fast retraction of droplet, forming irregular-hill freezing shape whose size enlarged with decreasing temperature. On rough surface, because of the later nucleation after retraction process finished, the freezing morphology showed convergent sphere shape with supercooling-independent freezing size; (3) considering more complicated impact dynamics, including breaking and bouncing, on different superhydrophobic surfaces, an impact-freezing model was established and could be used to estimate the average frozen spreading ratio.

A perspective article by international scientists underscores a critical new dimension to the global plastic crisis: Plastic pollution is not just harming wildlife and human health, but also disrupting the Earth’s carbon cycle in profound and lasting ways.

Wearable microfluidic sensors are promising for efficient sweat analysis, with applications in sports, healthcare, worker safety, and more fields. Recently, researchers from Chung-Ang University have successfully demonstrated next-generation soft, skin-interfaced 3D microfluidic systems for accurate and comprehensive sweat rate, cumulative loss, and biochemical content assessment. This cutting-edge technology is expected to revolutionize real-time and non-invasive tracking of health status and disease progression.