Vegetation biomass is a key and active component of the carbon cycle. Though China's vegetation biomass in recent decades has been widely investigated, only two studies have quantitatively assessed ...its century-scale changes so far and reported totally opposite trends. This study provided the first multi-model estimates of China's vegetation biomass change for the 20th century and its responses to historical changes in environmental and anthropogenic factors, based on simulations evaluated with the field observations from 3757 inventory plots in China and bias-corrected using machine learning (Gaussian process regression). A significant decline in vegetation biomass over the 20th century was shown by bias-corrected simulations from the six Dynamic Global Vegetation models (DGVMs) with trends ranging from −32.48 to −11.10 Tg C yr-1 and a mean trend of −17.74 Tg C yr-1. Land use and land cover change (LULCC) was primarily responsible for the simulated downward trend (−50.71 to −24.28 Tg C yr-1), while increasing atmospheric CO2 concentration lead to increased vegetation biomass (+9.27 to + 13.37 Tg C yr-1). Climate change had limited impacts on the long-term trend (−3.75 to + 5.06 Tg C yr-1). This study highlights the importance of LULCC for historical reconstruction and future projection of vegetation biomass over China. It also suggests that the incorrect change in China's forest area for 1980-2000 in the LULCC dataset used as model input data of many existing and ongoing model intercomparison projects (MIPs) has likely led to inaccurate estimations of historical vegetation biomass changes in China.
This study aimed to prevent water flow in microcracks and simultaneously achieve CO2 capture during grouting (CCG). Using sodium silicate (SS) as the primary material, the microcracks were grouted by ...a two-step approach. The low-initial-viscosity (5 mPa s) SS was first saturated within the microcracks followed by CO2 injection at 2 MPa. Through CO2 dissolution, silica gel was developed and tolerated a hydraulic pressure of up to 5.5 MPa. The effects of aquifer ions (Na+, Ca2+, Mg2+, HCO3 –, and SO4 2–) were equally evaluated at harsh conditions, and it was found that the strength of the silica gel was reduced, which was caused by salting out, low CO2 solubility, and precipitation. As a result, the hydraulic pressure was reduced to as low as 3 MPa. After 210 days, 16% of the silica gels (without ion inclusion) were reversible to the liquid phase, where a similar effect was found in the cases of Na+ and Mg2+ ions. The degradation increased with more Ca2+ ions (up to 55%) and decreased with more HCO3 – and SO4 2– ions. Microcracks grouted with CCG extended the CO2 utilization in grouting application. Combined with the effect of dissolved ions, the proposed approach is feasible in the field implementation for underground engineering under water bodies.
The species in family Planctomycetaceae are ideal groups for investigating the origin of eukaryotes. Their cells are divided by a lipidic intracytoplasmic membrane and they share a number of ...eukaryote-like molecular characteristics. However, their genomic structures, potential abilities, and evolutionary status are still unknown. In this study, we searched for common protein families and a core genome/pan genome based on 11 sequenced species in family Planctomycetaceae. Then, we constructed phylogenetic tree based on their 832 common protein families. We also annotated the 11 genomes using the Clusters of Orthologous Groups database. Moreover, we predicted and reconstructed their core/pan metabolic pathways using the KEGG (Kyoto Encyclopedia of Genes and Genomes) orthology system. Subsequently, we identified genomic islands (GIs) and structural variations (SVs) among the five complete genomes and we specifically investigated the integration of two Planctomycetaceae plasmids in all 11 genomes. The results indicate that Planctomycetaceae species share diverse genomic variations and unique genomic characteristics, as well as have huge potential for human applications.
Optical imaging in the second near-infrared (NIR-II; 900–1880 nm) window is currently a popular research topic in the field of biomedical imaging. This study aimed to explore the application value of ...NIR-II fluorescence imaging in footandankle surgeries. A lab-established NIR-II fluorescence surgical navigation system was developed and used to navigate foot and ankle surgeries which enabled obtaining more high-spatial-frequency information and a higher signal-to-background ratio (SBR) in NIR-II fluorescence images compared to NIR-I fluorescence images; our result demonstrates that NIR-II imaging could provide higher-contrast and larger-depth images to surgeons. Three types of clinical applicationscenarios (diabetic foot, calcaneal fracture, and lower extremity trauma) were included in this study. Using the NIR-II fluorescence imaging technique, we observed the ischemic region in the diabetic foot before morphologicalalterations, accurately determined the boundary of the ischemic region in the surgical incision, and fully assessed the blood supply condition of the flap. NIR-II fluorescence imaging can help surgeons precisely judge surgical margins, detect ischemic lesions early, and dynamically trace the perfusion process. We believe that portable and reliable NIR-II fluorescence imaging equipment and additional functional fluorescent probes can play crucial roles in precision surgery.
Critical patients in intensive care unit (ICU) are highly susceptible to acquiring carbapenem-resistant
(CRAB) infection. To investigate the relationship between nosocomial infections and ...environmental health, we studied the distribution and homology of CRAB isolates from patients and environment and evaluated the effectiveness of infection control measures.
In the 4-month study, we conducted a monthly CRAB screening of the ICU environment prior to disinfection in a Chinese teaching hospital. The ICU underwent routine disinfection procedures twice a day. We collected samples from the environment around the patients before disinfection. Clinical specimens from patients were also screened. The samples obtained were studied for phenotype and homology via antibiotic susceptibility testing, pulsed-field gel electrophoresis (PFGE), and whole-genome sequencing (WGS).
Ten specimens were sampled from ICU environments. Five were obtained in May 2020, and sputums from patient a in bed A at this time were cultured for CRAB isolates; in June 2020 another 5 environmental specimens were obtained from the same bed unit for CRAB, and sputums from patient b in bed A at this time were also cultured for CRAB isolates. Following intensive infection control measures, environmental sampling was negative in July and August. These 18 CRAB isolates all carried
and
genes and showed a similar resistance phenotype. WGS showed a close relationship among specimens from patients' sputum and their surroundings, but no homology between patients.
The analysis of cgMLST and SNPs is more accurate for strain homology analysis. Our data confirm that CRAB isolates spread from patient to environment in ICU; however, contact isolation and disinfection measures are effective in avoiding transmission, highlighting the importance of continued education and surveillance of CRAB. WGS could provide rich information on antimicrobial resistance, which is of great value in scientific research and clinical diagnosis.
Deep Neural Networks (DNNs) are vulnerable to adversarial examples, while adversarial attack models, e.g., DeepFool, are on the rise and outrunning adversarial example detection techniques. This ...paper presents a new adversarial example detector that outperforms state-of-the-art detectors in identifying the latest adversarial attacks on image datasets. Specifically, we propose to use sentiment analysis for adversarial example detection, qualified by the progressively manifesting impact of an adversarial perturbation on the hidden-layer feature maps of a DNN under attack. Accordingly, we design a modularized embedding layer with the minimum learnable parameters to embed the hidden-layer feature maps into word vectors and assemble sentences ready for sentiment analysis. Extensive experiments demonstrate that the new detector consistently surpasses the state-of-the-art detection algorithms in detecting the latest attacks launched against ResNet and Inception neutral networks on the CIFAR-10, CIFAR-100 and SVHN datasets. The detector only has about 2 million parameters, and takes shorter than 4.6 milliseconds to detect an adversarial example generated by the latest attack models using a Tesla K80 GPU card.
A method combining chemical and biological experiments and computer‐aided molecular design was used to optimize lead compounds with inhibiting activity against Sphaerotheca fuliginea. 44 ...propiophenone oxime derivatives were synthesized by 3‐amino‐1‐arylpropan‐1‐one oxime and halohydrocarbon. The results of biological test showed that most of these compounds had inhibiting activity against Sphaerotheca fuliginea. QSAR study was done based on the experimental data of the 44 compounds. CoMFA (rCV2, S and r2 are 0.577, 0.258 and 0.962, respectively) and CoMSIA (rCV2, S and r2 are 0.583, 0.343 and 0.932 respectively) models were contributed and employed to design three new lead compounds whose prediction carcinogenic and mutagenic toxicities show impossibility. The performances of the two models are satisfied because the test results showed that their prediction activity and observed activity are corresponding.
Two lead compounds were designed based on the CoMFA and CoMSIA models constructed by experimental data. Their predicted and observed bioactivities are corresponding.
Graphene is promising for nanoscale, efficient, ultra-fast photo- and opto-electronic devices because of its remarkable electrical and optical properties, such as fast electron relaxation and heat ...dissipation. Here, we realize high-performance graphene integrated photonics platform enabled by gold-assisted transfer. Thanks to our optimized transfer technique, we fabricate and demonstrate (1) a microscale thermo-optic modulator with a tuning efficiency of 0.037 nm/mW and high heating performance of 67.4 K\({\mu}m^{3}mW^{-1}\) on a small active area of 7.54 \({\mu}m^{2}\) and (2) a graphene electro-absorption modulator featuring an high modulation bandwidth up to 26.8 GHz and a high-speed data rate reaching 48 Gb/s, and (3) a graphene Mach-Zehnder interferometer modulator with a high normalized modulation efficiency of 0.027 dBV\(^{-1}{\mu}m^{-1}\). Our graphene integrated photonics platform has far superior performances compared to state of the art in terms of efficiency, low process complexity, and compact device footage. Thus, our approach and results provide the background for the realization of high-performance integrated photonic circuits with CMOS compatibility.
Early exiting allows instances to exit at different layers according to the estimation of difficulty. Previous works usually adopt heuristic metrics such as the entropy of internal outputs to measure ...instance difficulty, which suffers from generalization and threshold-tuning. In contrast, learning to exit, or learning to predict instance difficulty is a more appealing way. Though some effort has been devoted to employing such "learn-to-exit" modules, it is still unknown whether and how well the instance difficulty can be learned. As a response, we first conduct experiments on the learnability of instance difficulty, which demonstrates that modern neural models perform poorly on predicting instance difficulty. Based on this observation, we propose a simple-yet-effective Hash-based Early Exiting approach (HashEE) that replaces the learn-to-exit modules with hash functions to assign each token to a fixed exiting layer. Different from previous methods, HashEE requires no internal classifiers nor extra parameters, and therefore is more efficient. Experimental results on classification, regression, and generation tasks demonstrate that HashEE can achieve higher performance with fewer FLOPs and inference time compared with previous state-of-the-art early exiting methods.
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