The Artificial Intelligence of Things (AIoT) connects everything with intelligence, while the increase in energy consumption generated by numerous electronic devices puts forward an impending demand ...on the power supply. Energy harvesting technology has emerged as a compelling innovation technology for the net zero emissions of the power supply for the AIoT. Although significant advances have been witnessed in energy harvesting, some issues such as poor electrical output, weak environmental adaptability, and low reliability are difficult to satisfactorily resolve. Mechanical intelligent energy harvesting can be defined as the system identifying the external excitation or its own state and reacting to it, rather than relying on electrical sensing elements or a central controller for certain adaptive or programmed functions. The adaptive and programmed functions exhibit great potential in solving the above‐mentioned issues that seriously restrict the development of the energy harvesting technology. Here, a generalized definition of mechanical intelligent energy harvesting is given critically and the design methodology is elaborated. The typical reported energy harvesting systems with the characteristics of mechanical intelligence are reviewed. The key research directions in mechanical intelligent energy harvesting are discussed. The mechanical intelligence is expected to revolutionize the development of the energy‐harvesting technology and pave the way for applications.
Mechanical intelligent energy harvesting (MIEH) can be defined as the system identifying excitation or its own state and reacting to it, rather than relying on electrical sensing elements or central controllers for certain adaptive or programmed functions. This review proposes a generalized definition and methodology of MIEH for the first time, reviewing state‐of‐the‐art research, and discussing directions for future developments.
A series of Mo single-atom catalysts were prepared by calcining a low-cost primary material of urea with various amounts of Na
2
MoO
4
·2H
2
O. Isolated Mo centers are immobilized on
in situ
formed ...polymeric carbon nitride
via
coordinating with two N donors to form two-coordinated MoN
2
species. The low-coordinated Mo centers can serve as active sites for N
2
chemisorption and activation, achieving high photocatalytic activity for NH
3
evolution with a rate of 50.9 μmol g
cat
−1
h
−1
in pure water. In the presence of ethanol as the electron scavenger, the NH
3
evolution rate can reach 830 μmol g
cat
−1
h
−1
, and the catalyst shows a quantum efficiency of 0.70% at 400 nm. This is the first single-atom catalyst that can drive photocatalytic N
2
fixation in pure water with comparable performance to recent reports for photocatalytic N
2
reduction. Experimental investigations and density functional theory calculations demonstrate that the coordinatively unsaturated metal center in the single-atom catalysts can strongly adsorb N
2
via
an end-on configuration to elongate the N&z.tbd;N bond from 1.11 Å to 1.15 Å, and thus photoexcited electrons can transfer to the weakened N&z.tbd;N bond for efficient nitrogen fixation under ambient conditions. These findings provide new insight for solar-driven N
2
fixation by atomically dispersing low-coordination metal centers on photoactive supports.
A series of single-atom Mo-PCN photocatalysts were facilely and large-scale prepared. The two-coordinated Mo center can serve as active site for N
2
chemisorption and activation, first achieving solar-driven N
2
reduction in pure water under ambient conditions.
Abstract
Atomically thin two-dimensional semiconducting materials integrated into van der Waals heterostructures have enabled architectures that hold great promise for next generation ...nanoelectronics. However, challenges still remain to enable their applications as compliant materials for integration in logic devices. Here, we devise a reverted stacking technique to intercalate a wrinkle-free boron nitride tunnel layer between MoS
2
channel and source drain electrodes. Vertical tunnelling of electrons therefore makes it possible to suppress the Schottky barriers and Fermi level pinning, leading to homogeneous gate-control of the channel chemical potential across the bandgap edges. The observed features of ambipolar
pn
to
np
diode, which can be reversibly gate tuned, paves the way for future logic applications and high performance switches based on atomically thin semiconducting channel.
Abstract
Background
The impact of SARS-CoV-2 variants of concern (VOCs) on disease severity is unclear. In this retrospective study, we compared the outcomes of patients infected with B.1.1.7, ...B.1.351, and B.1.617.2 with wild-type strains from early 2020.
Methods
National surveillance data from January to May 2021 were obtained and outcomes in relation to VOCs were explored. Detailed patient-level data from all patients with VOC infection admitted to our center between December 2020 and May 2021 were analyzed. Clinical outcomes were compared with a cohort of 846 patients admitted from January to April 2020.
Results
A total of 829 patients in Singapore in the study period were infected with these 3 VOCs. After adjusting for age and sex, B.1.617.2 was associated with higher odds of oxygen requirement, intensive care unit admission, or death (adjusted odds ratio aOR, 4.90; 95% confidence interval CI: 1.43-30.78). Of these patients, 157 were admitted to our center. After adjusting for age, sex, comorbidities, and vaccination, the aOR for pneumonia with B.1.617.2 was 1.88 (95% CI: .95-3.76) compared with wild-type. These differences were not seen with B.1.1.7 and B.1.351. Vaccination status was associated with decreased severity. B.1.617.2 was associated with significantly lower polymerase chain reaction cycle threshold (Ct) values and longer duration of Ct value ≤30 (median duration 18 days for B.1.617.2, 13 days for wild-type).
Conclusions
B.1.617.2 was associated with increased severity of illness, and with lower Ct values and longer viral shedding. These findings provide impetus for the rapid implementation of vaccination programs.
In this retrospective cohort study we found an association between infection with B.1.617.2 (Delta) and increased disease severity. B.1.617.2 was also associated with higher viral loads and prolonged duration of viral shedding. Vaccination remained protective.
In-vitro metabolite and drug detection rely on designed materials-based analytical platforms, which are universally used in biomedical research and clinical practice. However, metabolic analysis in ...bio-samples needs tedious sample preparation, due to the sample complexity and low molecular abundance. A further challenge is to construct diagnostic tools. Herein, we developed a platform using silver nanoshells. We synthesized SiO
@Ag with tunable shell structures by multi-cycled silver mirror reactions. Optimized nanoshells achieved direct laser desorption/ionization mass spectrometry in 0.5 μL of bio-fluids. We applied these nanoshells for disease diagnosis and therapeutic evaluation. We identified patients with postoperative brain infection through daily monitoring and glucose quantitation in cerebrospinal fluid. We measured drug distribution in blood and cerebrospinal fluid systems and validated the function of blood-brain/cerebrospinal fluid-barriers for pharmacokinetics. Our work sheds light on the design of materials for advanced metabolic analysis and precision diagnostics.Preparation of samples for diagnosis can affect the detection of biomarkers and metabolites. Here, the authors use a silver nanoparticle plasmonics approach for the detection of biomarkers in patients as well as investigate the distribution of drugs in serum and cerebral spinal fluid.
A green and efficient visible-light-induced iodosulfonyl reaction of alkenes in water using an EDA complex strategy at room temperature has been disclosed. The addition of a cationic surfactant ...allows for the easy formation of colored EDA complexes in water. The hydrophobic effect of the core in the surfactant aggregates, which act as a reaction medium formed by the surfactants themselves in water, plays a significant role in stabilizing the transition state and decreasing the activation energy of the reaction. Remarkably, transition-metal catalysts and organic solvents were not required in this transformation. Moreover, it displayed a broad substrate scope, good functional group tolerance, simple operation, scalability and high chemical selectivity. Thus, it not only provided a green and efficient synthetic strategy for the preparation of β-iodo-substituted sulfone derivatives, but also enriched the investigation of visible-light-induced reactions in water.
We report an efficient visible-light-induced iodosulfonyl reaction of alkenes in water using an EDA complex strategy at room temperature. The addition of a cationic surfactant allows for the easy formation of colored EDA complexes in water.
Mechanical damage or infection to the endometrium can lead to the formation of adhesions in the uterine cavity, which may result in reduced reproductive outcome and/or pregnancy complications. The ...prognosis of this disease is poor due to few effective treatments and the complex environment of endometrium. Heparin‐Poloxamer Hydrogel (HP hydrogel) is a nontoxic and biodegradable biomaterial, which has been commonly used as a sustained‐release delivery system. In this study, we applied a mini‐endometrial curette to scrape the endometrium of rats to mimic the process of curettage in patients. After the establishment of IUA model in rats, we injected the thermo‐sensitive hydrogel(E2‐HP hydrogel) into the injured uterine cavity and evaluated the therapeutic effect of E2‐HP hydrogel on the recovery of IUA. Our results showed that E2‐HP hydrogel can significantly facilitate the regeneration of injured endometrium along with inhibiting the cell apoptosis in IUA model. Furthermore, we revealed that E2‐HP hydrogel on the recovery of IUA was closely associated with the upregulation of kisspeptin through activating the ERK1/2 and MAPKs p38 pathways. In conclusion, E2‐HP hydrogel can effectively transfer E2 into the injured endometrium and it can be considered as a promising therapeutic method for the women with intrauterine adhesions.
Accurate glioma grading before surgery is of the utmost importance in treatment planning and prognosis prediction. But previous studies on magnetic resonance imaging (MRI) images were not effective ...enough. According to the remarkable performance of convolutional neural network (CNN) in medical domain, we hypothesized that a deep learning algorithm can achieve high accuracy in distinguishing the World Health Organization (WHO) low grade and high grade gliomas.
One hundred and thirteen glioma patients were retrospectively included. Tumor images were segmented with a rectangular region of interest (ROI), which contained about 80% of the tumor. Then, 20% data were randomly selected and leaved out at patient-level as test dataset. AlexNet and GoogLeNet were both trained from scratch and fine-tuned from models that pre-trained on the large scale natural image database, ImageNet, to magnetic resonance images. The classification task was evaluated with five-fold cross-validation (CV) on patient-level split.
The performance measures, including validation accuracy, test accuracy and test area under curve (AUC), averaged from five-fold CV of GoogLeNet which trained from scratch were 0.867, 0.909, and 0.939, respectively. With transfer learning and fine-tuning, better performances were obtained for both AlexNet and GoogLeNet, especially for AlexNet. Meanwhile, GoogLeNet performed better than AlexNet no matter trained from scratch or learned from pre-trained model.
In conclusion, we demonstrated that the application of CNN, especially trained with transfer learning and fine-tuning, to preoperative glioma grading improves the performance, compared with either the performance of traditional machine learning method based on hand-crafted features, or even the CNNs trained from scratch.
In recent years, we have witnessed the exponential proliferation of the Internet of Things (IoT)-based networks of physical devices, vehicles, and appliances, as well as other items embedded with ...electronics, software, sensors, actuators, and connectivity, which enable these objects to connect and exchange data ....
Flexible and self-supported carbon-coated FeS on carbon cloth films (denoted as FeS@C/carbon cloth) is prepared by a facial hydrothermal method combined with a carbonization treatment. The ...FeS@C/carbon cloth could be directly used as electrodes for Li-ion batteries (LIBs) and sodium-ion batteries (NIBs). The synthetic effects of the structure, highly electron-conductive of carbon cloth, porous structure for electrolyte access, and uniform carbon shell on FeS surface to accommodate the volume change lead to improved cyclability and rate capability. For lithium storage, the FeS@C/carbon cloth electrode delivers a high discharge capacity of 420 mAh g–1 even after 100 cycles at a current density of 0.15 C and 370 mAh g–1at a high current density of 7.5 C (1 C = 609 mA g–1. When used for sodium storage, it keeps a reversible capacity of 365 mAh g–1after 100 cycles at 0.15 C. Similar process can be utilized for the formation of various cathode and anode composites on carbon cloth for flexible energy storage devices.
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