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Widespread consistent but rapid response of terrestrial ecosystem photosynthesis and respiratory to drought
No full textDrought significantly threatens terrestrial ecosystems health, through influencing both photosynthesis and respiratory processes. However, whether these processes have changed in response to intensified drought and the driving mechanisms remain unclear, even though the inconsistent responses may indicate an increased potential for unstable carbon sinks. The knowledge gap would hinder accurate prediction of the size of China's future terrestrial ecosystems carbon sink under increasing extreme droughts, thus impacting the realization of China's carbon neutrality goal. Here, we combined observational-based data and dynamic global vegetation model data to explore the response time (RT) of Gross Primary Productivity (GPP) and Ecosystem Respiration (TER) to meteorological drought in China and their dynamics over the past 40 years. Results reveal consistent spatial distribution patterns in GPP and TER responses to drought. During 1982–2021, widespread declines in the RT of both GPP and TER to drought were observed, indicating an increased likelihood of vegetation converting from a carbon sink into a carbon source under droughts. GPP responds slightly faster than TER, notably in arid regions influenced by land cover change and climate change. Hotspots of decreasing RT trends, such as the Tibetan Plateau and Yellow River Basin, underscore the diverse impacts of climate and land cover changes. Our findings shed new insights into ecosystem carbon fluxes mechanisms, thus providing accurate carbon budget for China's carbon neutrality goal
Preparation of nickel nanoparticle-decorated graphene/copper composites with enhanced interfacial bonding and heat dissipation properties
No full textBecause of its high thermal conductivity, graphene has been considered as an ideal reinforcement material in the fabrication of metal-based heat dissipation composite materials for electronic packaging applications. However, due to the poor interfacial bonding between graphene and metals such as copper and silver, the excellent performance of graphene has not been fully utilized, which greatly limits the development and application of metal/graphene composites. In this study, we propose a modification process of graphene, in which nickel nanoparticles with an average size of 72.8 nm are grown on oxygen plasma treated graphene (OPTG) by thermal reduction to yield a number density of 70 nanoparticles/μm2. The OPTG sheets decorated with nickel nanoparticles (Ni-OPTG) are added to copper nanoparticles as reinforcing layers to form Ni-OPTG/copper (Ni-OPTG/Cu) composites. Because the nickel nanoparticles can form C-O-Ni bonds with OPTG, and be easily sintered with copper, the interfacial bonding of the graphene/copper composite is enhanced, and the heat conductivity and shear strength of the sintered composite can be significantly improved. With the addition of only 0.1 wt% Ni-OPTG, the sintered copper/graphene composite achieve a thermal conductivity of 216.2 W/m·K and a shear strength of 56.3 MPa, which are 105.3 % and 87.3 % larger than the corresponding values of sintered copper nanoparticles, respectively. With these advantages, the Ni-OPTG/Cu composites have an excellent potential for use in packaging applications for high-power electronic chips and devices
Consumer perception of employees with disabilities using robots
No full textAdvanced robotic technologies provide direct assistance to people with disabilities in overcoming physical barriers. We examine how consumers respond to frontline service employees with disabilities who utilize such technologies. Across three studies, we demonstrate that not all technologies are perceived equally: consumers tend to respond negatively to employees with disabilities who are telepresent via robots compared to those who work in person, regardless of whether the latter use assistive technology (e.g., wearable robots). Our findings suggest that companies focused on social inclusivity should consider investing in wearable robotic technologies instead of telepresence robots to reduce physical barriers for frontline employees with disabilities while improving their working conditions
Mpox virus poxin-schlafen fusion protein suppresses innate antiviral response by sequestering STAT2
No full textMpox virus (MPXV) has to establish efficient interferon (IFN) antagonism for effective replication. MPXV-encoded IFN antagonists have not been fully elucidated. In this study, the IFN antagonism of poxin-schlafen (PoxS) fusion gene of MPXV was characterized. MPXV PoxS was capable of decreasing cGAS-produced 2'3'-cGAMP, like its ortholog poxin of vaccinia virus, which is the first known cytosolic nuclease that hydrolyses the 3'-5' bond of 2'3'-cyclic GMP-AMP (cGAMP). However, MPXV PoxS did not suppress cGAS-STING-mediated type I IFN production. Instead, MPXV PoxS antagonized basal and type I IFN-induced expression of IFN-stimulated genes such as OAS1, SAMD9, SAMD9L, ISG15, ISG56 and IFIT3. Consistently, MPXV PoxS inhibited both basal and type I IFN-stimulated activity of interferon-stimulated response elements, but did not affect activation of IFN-γ-activated sites. Mechanistically, MPXV PoxS interacted with STAT2 and sequestered it in the cytoplasm. Both the viral schlafen fusion and the active site of 2'3'-cGAMP nuclease were required for STAT2 sequestration and consequent suppression of IFN-stimulated gene expression. MPXV PoxS conferred resistance to the suppression of MPXV replication by type I IFN. Taken together, our findings suggested that MPXV PoxS counteracts host antiviral response by sequestering STAT2 to circumvent basal and type I IFN-induced expression of antiviral genes.</p
Technology-enhanced content and language integrated learning: A systematic review of empirical studies
No full textContent and language integrated learning (CLIL), i.e., learning subject content in a non-native language, has been widely promoted as an innovative way of teaching English as a foreign language. More recently, technology is integrated in CLIL programs. In view of the growing number of studies on technology-enhanced CLIL (TECLIL) and the limitations of previous reviews in this field, this paper presents a systematic review of empirical studies on TECLIL. Based on the findings from 20 articles published in Social Science Citation Index (SSCI) journals (2014–2023), this review summarizes the key characteristics of the empirical studies on TECLIL, the types of technology applied in TECLIL programs, the learning outcomes reported in TECLIL studies, and exemplary cases demonstrating the design and implementation of TECLIL in practice. Seven types of technology applied in TECLIL programs are identified. Telecollaboration tools are the most frequently used, followed by online learning platforms, multimedia, virtual learning environments, social network applications, language tools, and intelligent conversation tools. The language skills explored in TECLIL programs focus on productive skills (e.g., speaking and writing) rather than receptive skills (e.g., listening and reading). Cognitive learning outcomes in terms of subject knowledge and language skills are commonly assessed in TECLIL studies, with less attention to affective outcomes. Overall, the use of technology has yielded a small effect (effect size = 0.29) on content knowledge acquisition, but no substantial effect (effect size = 0.16) on language achievement. Although there is a growing body of research on TECLIL, more empirical studies are needed to determine effective design of TECLIL programs and the effects of TECLIL on both cognitive and affective outcomes
Geolocator Tracking and Stable Isotope Analysis Suggest Mixed Migration Strategies in White-Shouldered Starlings (Sturnia sinensis)
No full textThe East Asian–Australasian Flyway (EAAF) is one of the least studied flyways, especially for migratory passerines. A better understanding of the migratory behaviour of birds along the EAAF is critical to inform conservation efforts and to improve the understanding of the evolution of migratory behaviour. White-shouldered starlings (Sturnia sinensis) breed in southern China and northern Vietnam, with at least some populations migrating to distinct wintering grounds. Using a combination of extrinsic (geolocators) and intrinsic markers (stable isotopes), we tested whether a presumed resident breeding population in Hong Kong is resident or migratory. We discovered that most tagged individuals (7/8) migrated southwest from Hong Kong to winter in Vietnam/Cambodia up to 2013 km from their breeding grounds. We also found evidence of an alternative migration pathway, with one individual migrating northeast to overwinter in southern China. Stable isotope analyses of feathers revealed that the northeast-migrating individual had different δ2H and δ34S values than those migrating southeast in that year (but had similar isotope values in the previous year). Based on isotope data alone, a second individual was identified who had distinct δ2H and δ34S values between years, suggesting that this individual also switched wintering grounds between the two breeding seasons. Together our results confirm that the Hong Kong breeding population is migratory, and both geolocator and stable isotope data suggest that the Hong Kong population of this species might host at least two different migration strategies, with some individuals switching their wintering grounds between years.</p
MRI Detection of Unknown Primary Tumours in the Head and Neck: What Is the Expected Normal Asymmetry in the Size of the Palatine Tonsils?
No full text Background/Objectives: The detection of unknown primary tumours in the palatine tonsils (PTs) on imaging relies heavily on asymmetry in size between the right and left sides, but the expected normal range in asymmetry is not well documented. This study aimed to document the expected range of asymmetry in the size of the PTs in adults without cancer. Methods: This retrospective study evaluated 250 pairs of normal PTs on MRIs of adults without head and neck cancer. The size (volume, V) of the PTs on the left and right sides were measured, and the percentage difference in volume (ΔV%) between the two sides was calculated. An additional analysis of PT volumes in 29 patients with ipsilateral early-stage palatine tonsillar cancer (PTCs) was performed. Results: In patients without PTC, the normal PTs had a mean volume of 3.0 ± 1.7 cm3, and there was a difference in size between the left and right PTs, showing a median ΔV% of 11.6% (range: 0.1–79.0%); most patients had a ΔV% of ≤40% (95%) for PTs. In patients with ipsilateral PTC, the normal PT had a smaller size compared with PTC (p 39.6% achieved the best accuracy of 95% for identifying PTC. Conclusions: PTs are asymmetrical in size in adults without PTC. An additional analysis involving patients with PTC confirmed a threshold of ΔV% of 40% for PTs, which may be clinically valuable to help detect pathology using MRI. </p
A language-focused book reading intervention to boost bilingual language development in Dai-Mandarin preschoolers in China
No full textEnhancing Stereochemistry Education through Inquiry-Based Learning and Concrete Molecular Models
Get PDFStereochemistry is a vital component of pharmacy education, yet students often find it challenging due to the complex spatial concepts involved. This paper presents an innovative learning activity that combines inquiry-based learning with concrete molecular models to facilitate students’ understanding of stereochemistry. The activity was structured around a three-phase learning cycle, including exploration, concept invention, and application and was scaffolded by mini-lectures. Students in small groups constructed and analyzed 3D molecular models of organic compound isomers and formulated definitions and rules for different types of isomerism based on the exploration. Concrete models to visualize molecular structures reduced students’ cognitive load and provided kinesthetic and proprioception stimulation. Feedback from participating students indicated positive reception of the activity, highlighting the benefits of using concrete models and small group interactions. This innovative approach has demonstrated the potential of making stereochemistry more engaging and accessible for students.published_or_final_versio