The world’s earliest Aral-Sea type disaster: the decline of the Loulan Kingdom in the Tarim Basin

The presented data are accessible in the PANGAEA database, https://doi.pangaea.de/10.1594/PANGAEA.871173.Remnants of cities and farmlands in China’s hyperarid Tarim Basin indicate that environmental conditions were significantly wetter two millennia ago in a region which is barren desert today. Historical documents and age data of organic remains show that the Loulan Kingdom flourished during the Han Dynasty (206 BCE–220 CE) but was abandoned between its end and 645 CE. Previous archaeological, geomorphological and geological studies suggest that deteriorating climate conditions led to the abandonment of the ancient desert cities. Based on analyses of lake sediments from Lop Nur in the eastern Tarim Basin and a review of published records, we show that the Loulan Kingdom decline resulted from a man-made environmental disaster comparable to the recent Aral Sea crisis rather than from changing climate. Lop Nur and other lakes within the Han Dynasty realm experienced rapidly declining water levels or even desiccation whilst lakes in adjacent regions recorded rising levels and relatively wet conditions during the time of the Loulan Kingdom decline. Water withdrawal for irrigation farming in the middle reaches of rivers likely caused water shortage downstream and eventually the widespread deterioration of desert oases a long time before man initiated the Aral Sea disaster in the 1960s.Funding was provided by China’s NSF projects (40830420, 41471003), the State key project (2003BA612A-06–15) of the Ministry of Science and Technology of China and the German Research Foundation (DFG grant Mi 730/16-1). We thank two anonymous reviewers who provided very constructive comments on an earlier version of this paper.Peer Reviewe

Efficiency and risk in sustaining China’s food production and security: Evidence from micro-level panel data analysis of Japonica rice production

Sustainable food production and food security are always challenging issues in China. This paper constructs a multi-element two-level constant-elasticity-of-substitution (CES) model to assess technological progress in, and its contribution to, japonica rice production in China. The results show that the speed of technological progress in the production of japonica rice on average was 0.44% per annum in 1985–2013, and technological progress has contributed significantly to the growth of japonica rice production in China. Robustness checks show that the results appear to be sensitive to which sub-sample is used. Labour and some other inputs are found to be significant but negative, especially during the middle sampling period of 1994–2006 and in eastern and western regions. This has important policy implications on the impact of rural-to-urban migration and farmers’ human development. View Full-Tex

Professional Characteristics Influencing Work Engagement of Rural Early Childhood Teachers

Rural early childhood teachers' work engagement directly impacts their professional development and significantly influences the quality of the early childhood education system. However, rural early childhood teachers in China face numerous challenges in maintaining high levels of work engagement. This study used the Utrecht Work Engagement Scale (UWES) to examine the relationship between professional characteristics and work engagement among 530 rural early childhood teachers. The results showed that teaching tenure, educational level, professional background, and other factors significantly affected their work engagement

Study on a Strong Polymer Gel by the Addition of Micron Graphite Oxide Powder and Its Plugging of Fracture

It is difficult to plug the fracture water channeling of a fractured low-permeability reservoir during water flooding by using the conventional acrylamide polymer gel due to its weak mechanical properties. For this problem, micron graphite powder is added to enhance the comprehensive properties of the acrylamide polymer gel, which can improve the plugging effect of fracture water channeling. The chemical principle of this process is that the hydroxyl and carboxyl groups of the layered micron graphite powder can undergo physicochemical interactions with the amide groups of the polyacrylamide molecule chain. As a rigid structure, the graphite powder can support the flexible skeleton of the original polyacrylamide molecule chain. Through the synergy of the rigid and flexible structures, the viscoelasticity, thermal stability, tensile performance, and plugging ability of the new-type gel can be significantly enhanced. Compared with a single acrylamide gel, after adding 3000 mg/L of micrometer-sized graphite powder, the elastic modulus, the viscous modulus, the phase transition temperature, the breakthrough pressure gradient, the elongation at break, and the tensile stress of the acrylamide gel are all greatly improved. After adding the graphite powder to the polyacrylamide gel, the fracture water channeling can be effectively plugged. The characteristics of the networked water flow channel are obvious during the injected water break through the gel in the fracture. The breakthrough pressure of water flooding is high. The experimental results are an attempt to develop a new gel material for the water plugging of a fractured low-permeability reservoir

Current Status and Influencing Factors of Social Support for Rural Early Childhood Teachers

The development of rural preschool education can not be separated from rural early childhood teachers.  Research has indicated that social support is associated with better work performance of teachers. The social support scale was used to study the social support status of rural preschool teachers in Yunnan Province of China. The results show that the social support level of rural early childhood teachers is medium; the level of perceived social support is influenced by factors such as age, total monthly income, and educational level

CHARACTERIZATION OF A MICROPUMP ACTUATED BY TERNARY TiNiCu SHAPE MEMORY THIN FILMS

ABSTRACT Thin film SMAs have the potential to became a primary actuating mechanism for micropumps. In this study, a micropump driven by TiNiCu shape memory thin film is designed and fabricated. The micropump is composed of a TiNiCu/Si bimorph driving membrane, a pump chamber and two inlet and outlet check valves. The thickness, surface morphology and phase transformation property of TiNiCu film have been characterized by scanning electron microscope (SEM), atomic force microscopy (AFM), differential scanning calorimeters (DSC). Driving capacity of TiNiCu/Si biomorphic driving membrane has been investigated. The film surface shows a smooth and featureless morphology without any cracks, and the hysteresis width ∆T of TiNiCu film is about 10 ºC. By using the recoverable force of TiNiCu thin film, the actuation diaphragm realizes reciprocating motion effectively. Experimental results show that the micropump driving by TiNiCu film has good performance, such as high working frequency, stable driving capacity, and long fatigue life time

Arondight: Red Teaming Large Vision Language Models with Auto-generated Multi-modal Jailbreak Prompts

Large Vision Language Models (VLMs) extend and enhance the perceptual abilities of Large Language Models (LLMs). Despite offering new possibilities for LLM applications, these advancements raise significant security and ethical concerns, particularly regarding the generation of harmful content. While LLMs have undergone extensive security evaluations with the aid of red teaming frameworks, VLMs currently lack a well-developed one. To fill this gap, we introduce Arondight, a standardized red team framework tailored specifically for VLMs. Arondight is dedicated to resolving issues related to the absence of visual modality and inadequate diversity encountered when transitioning existing red teaming methodologies from LLMs to VLMs. Our framework features an automated multi-modal jailbreak attack, wherein visual jailbreak prompts are produced by a red team VLM, and textual prompts are generated by a red team LLM guided by a reinforcement learning agent. To enhance the comprehensiveness of VLM security evaluation, we integrate entropy bonuses and novelty reward metrics. These elements incentivize the RL agent to guide the red team LLM in creating a wider array of diverse and previously unseen test cases. Our evaluation of ten cutting-edge VLMs exposes significant security vulnerabilities, particularly in generating toxic images and aligning multi-modal prompts. In particular, our Arondight achieves an average attack success rate of 84.5\% on GPT-4 in all fourteen prohibited scenarios defined by OpenAI in terms of generating toxic text. For a clearer comparison, we also categorize existing VLMs based on their safety levels and provide corresponding reinforcement recommendations. Our multimodal prompt dataset and red team code will be released after ethics committee approval. CONTENT WARNING: THIS PAPER CONTAINS HARMFUL MODEL RESPONSES.Comment: To be published in ACM MM 202

Selection of antigenically advanced variants of seasonal influenza viruses.

Influenza viruses mutate frequently, necessitating constant updates of vaccine viruses. To establish experimental approaches that may complement the current vaccine strain selection process, we selected antigenic variants from human H1N1 and H3N2 influenza virus libraries possessing random mutations in the globular head of the haemagglutinin protein (which includes the antigenic sites) by incubating them with human and/or ferret convalescent sera to human H1N1 and H3N2 viruses. We also selected antigenic escape variants from human viruses treated with convalescent sera and from mice that had been previously immunized against human influenza viruses. Our pilot studies with past influenza viruses identified escape mutants that were antigenically similar to variants that emerged in nature, establishing the feasibility of our approach. Our studies with contemporary human influenza viruses identified escape mutants before they caused an epidemic in 2014-2015. This approach may aid in the prediction of potential antigenic escape variants and the selection of future vaccine candidates before they become widespread in nature.This work was supported by the Bill & Melinda Gates Foundation Global Health Grant OPPGH5383; National Institute of Allergy and Infectious Diseases (NIAID) Public Health Service research grants (USA); ERATO (Japan Science and Technology Agency); the Center for Research on Influenza Pathogenesis (CRIP) funded by the NIAID Contracts HHSN266200700010C and HHSN27 2201400008C; the Japan Initiative for Global Research Network on Infectious Diseases; Grants-in-Aid for Specially Promoted Research from the Ministry of Education, Culture, Sports, Science, and Technology, Japan; Grants-in-Aid from the Ministry of Health, Labour and Welfare, Japan; grants from the Strategic Basic Research Program of the Japan Science and Technology Agency; and by the Advanced Research & Development Programs for Medical Innovation from the Japan Agency for Medical Research and Development (AMED). C.A.R. was supported by a University Research Fellowship from the Royal Society. The authors acknowledge a Netherlands Organisation for Scientific Research (NWO) VICI grant, European Union (EU) FP7 programs EMPERIE (223498) and ANTIGONE (278976); Human Frontier Science Program (HFSP) program grant P0050/2008; Wellcome 087982AIA; and NIH Director's Pioneer Award DP1-OD000490-01. D.F.B and D.J.S. acknowledge CamGrid, the University of Cambridge distributed computer system. The Melbourne WHO Collaborating Centre for Reference and Research on Influenza is supported by the Australian Government Department of Health.This is the author accepted manuscript. The final version is available from Nature Publishing Group via http://dx.doi.org/10.1038/nmicrobiol.2016.5