Abstract One-dimensional carbon nanotubes are promising candidates for thermoelectrics because of their excellent electrical and mechanical properties. However, the large n-type power factor remains ...elusive in macroscopic carbon nanotubes films. Herein, we report an outstanding n-type power factor of 6.75 mW m −1 K −2 for macroscopic carbon nanotubes films with high electrical and thermal conductivity. A high-power density curl-able thermoelectric generator is fabricated with the obtained carbon nanotubes films, which exhibits a high normalized power output density of 2.75 W m −1 at a temperature difference of 85 K. The value is higher than that of previously reported flexible all-inorganic thermoelectric generators (<0.3 W m −1 ). An intelligent temperature controller with automated temperature-controlling ability is fabricated by assembling these thermoelectric generators, which demonstrates the potential application of the carbon nanotubes films in automated thermal management of electronic devices where requires a large thermoelectric power factor and a large thermal conductivity simultaneously.
Background
In recent years, studies have demonstrated that magnetic anchor-guided endoscopic submucosal dissection (MAG-ESD) is feasible and safe and may facilitate the treatment of all difficult ...lesions. However, the major problem with MAG-ESD is the inability to deliver the magnetic anchor to the gastrointestinal tract without withdrawal or reinsertion of the endoscope. Therefore, our team developed a magnetic anchor that could be easily inserted through the biopsy channel, facilitating ESD traction and evaluated its effectiveness and safety.
Methods
The study was conducted between October 2020 and June 2021 at The Second Affiliated Hospital of Harbin Medical University, China. One hundred and twelve patients with colorectal tumors treated with ESD were divided into two groups for historical control comparison. A channel-placed magnetic anchor (CPMAG) group and a control group consisting of patients who had conventional ESD without adjuvant traction. The rate of en bloc resection and resection with tumor-free lateral/basal margins (R0 resection), dissection speeds, procedure time, intraoperative bleeding and perforation complications, and postoperative follow-up were compared between the two groups, so as to evaluate the clinical effect and safety of the new magnetic anchor.
Results
The en bloc resection and R0 resection rate with CPMAG-ESD were slightly higher than with conventional ESD but this was not statistically significant. The median dissection speeds with CPMAG-ESD were higher than with conventional ESD, but the difference was not statistically significant. Intraoperative bleeding and postoperative complications with the CPMAG-ESD were less than with conventional ESD, but this was not statistically significant. The median operating time was shorter with CPMAG- ESD than with conventional ESD (24.5 min range 15.8–66.5 min vs 39 min range 29–58 min,
p
= 0.024), and this difference was statistically significant.
Conclusions
The new magnetic anchor-guided ESD technique appears to be a feasible and safe method for treating early colorectal tumors with en bloc resection, with improvement of the submucosal visual field, and less adverse events.
Conducting hydrogels have attracted much attention for the emerging field of hydrogel bioelectronics, especially poly(3,4‐ethylenedioxythiophene): poly(styrene sulfonate) (PEDOT:PSS) based hydrogels, ...because of their great biocompatibility and stability. However, the electrical conductivities of hydrogels are often lower than 1 S cm−1 which are not suitable for digital circuits or applications in bioelectronics. Introducing conductive inorganic fillers into the hydrogels can improve their electrical conductivities. However, it may lead to compromises in compliance, biocompatibility, deformability, biodegradability, etc. Herein, a series of highly conductive ionic liquid (IL) doped PEDOT:PSS hydrogels without any conductive fillers is reported. These hydrogels exhibit high conductivities up to ≈305 S cm−1, which is ≈8 times higher than the record of polymeric hydrogels without conductive fillers in literature. The high electrical conductivity results in enhanced areal thermoelectric output power for hydrogel‐based thermoelectric devices, and high specific electromagnetic interference (EMI) shielding efficiency which is about an order in magnitude higher than that of state‐of‐the‐art conductive hydrogels in literature. Furthermore, these stretchable (strain >30%) hydrogels exhibit fast self‐healing, and shape/size‐tunable properties, which are desirable for hydrogel bioelectronics and wearable organic devices. The results indicate that these highly conductive hydrogels are promising in applications such as sensing, thermoelectrics, EMI shielding, etc.
PEDOT:PSS hydrogels exhibit high conductivities up to ≈305 S cm−1, which is ≈8 times higher than the record of polymeric hydrogels without conductive fillers. The high electrical conductivity results in enhanced areal thermoelectric output power for hydrogel‐based thermoelectric devices, and high specific electromagnetic interference shielding efficiency (an order in magnitude higher than that of reported of state‐of‐the art conductive hydrogels).
Three hydrophobic charge-induction adsorbents with functional ligands of 4-mercapto-ethyl-pyridine, 2-mercapto-methyl-imidazole or 2-mercapto-benzimidazole were evaluated in the purification of ...porcine immunoglobulin from porcine blood. Adsorption isotherms were studied under different pH conditions. The adsorbent with 2-mercapto-methyl-imidazole as the ligand showed reasonable adsorption capacity（43.60 mg·g~（-1）gel）with great selectivity and it also showed the best elution performance in chromatographic studies. A multi-pH step elution process was proposed for the 2-mercapto-methyl-imidazole adsorbent, and the results showed that high immunoglobulin purity（94.3%） and a yield of 9.8 mg·（ml plasma）~（-1） could be achieved under the optimal condition of loading（pH 5.0）–pre-elution（pH 7.0）–elution（pH 3.8）. Moreover, molecular simulation was employed to help in analyzing the binding mechanism between the ligands and immunoglobulin, and the results showed that both 2-mercapto-benzimidazole and 2-mercapto-methyl-imidazole ligands were docked on the same pocket（around TYR319 and LEU309） of the Fc fragment of immunoglobulin, with 2-mercaptobenzimidazole showing stronger binding interactions.
Highly conductive hydrogels with biotissue‐like mechanical properties are of great interest in the emerging field of hydrogel bioelectronics due to their good biocompatibility, deformability, and ...stability. Fully polymeric hydrogels may exhibit comparable Young's modulus to biotissues. However, most of these filler‐free hydrogels have a low electrical conductivity of <10 S cm−1, which limits their wide applications of them in digital circuits or bioelectronic devices. In this work, a series of metal‐halides‐doped poly(3,4‐ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) hydrogels with an ultrahigh electrical conductivity up to 547 S cm−1 is reported, which is 1.5 times to 104 times higher than previously reported filler‐free polymeric hydrogels. Theoretical calculation demonstrated that the ion exchange between PEDOT:PSS and the metal halides played an important role to promote phase separation in the hydrogels, which thus leads to ultrahigh electrical conductivity. The high electrical conductivity resulted in multifunctional hydrogels with high performance in thermoelectrics, electromagnetic shielding, Joule heating, and sensing. Such flexible and stretchable hydrogels with ultrahigh electrical conductivity and stability upon various deformations are promising for soft bioelectronics devices and wearable electronics.
A series of metal‐halides‐doped poly(3,4‐ethylenedioxy thiophene): poly(styrene sulfonate) (PEDOT:PSS) hydrogels with an ultrahigh electrical conductivity up to 547 S cm−1 have been prepared that exhibited high performance in thermoelectrics, electromagnetic shielding, Joule heating, and sensing.
•Composite biomaterial ink in which the proportion of DECM is highest.•Composite biomaterial ink enabling enhanced activity of primary hepatocytes.•Composite biomaterial ink having both good ...biocompatibility and printability.
This study presented a composite biomaterial ink consisting of GelMA, decellularized extracellular matrix (DECM) and nanoclay for printing 3D scaffolds for primary hepatocytes cultivation. In this biomaterial ink, the proportion of DECM was 75%, which is the highest value ever reported. The high proportion of DECM resulted in high activity of primary hepatocytes, and enabled better organ-specific biomaterial ink.
Flexible photo‐thermoelectric (PTE) devices have great application prospects in the fields of solar energy conversion, ultrabroadband light detection, etc. A suitable manufacturing process to avoid ...the substrate effects as well as to create a narrow transition area between p–n modules for high‐performance freestanding flexible PTE devices is highly desired. Herein, an automated laser fabrication (ALF) method is reported to construct the PTE devices with rylene‐diimide‐doped n‐type single‐walled carbon nanotube (SWCNT) films. The wet‐compressing approach is developed to improve the thermoelectric power factors and figure of merit (ZT) of the SWCNT hybrid films. Then, the films are cut and patterned automatically to make PTE devices with various structures by the proposed ALF method. The freestanding PTE device with a narrow transition area of ≈2–3 µm between the p and n modules exhibits a high‐power density of 0.32 µW cm−2 under the light of 200 mW cm−2, which is among the highest level for freestanding‐film‐based PTE devices. The results pave the way for the automatic production process of PTE devices for green power generation and ultrabroadband light detection.
An all‐automated laser fabrication technique is reported for the preparation of flexible and freestanding photo‐thermoelectric (PTE) devices with single‐walled carbon nanotube films. The achieved PTE devices with a narrow p–n transition area of 2–3 µm exhibit high‐performance among the highest level for freestanding‐film‐based PTE devices.
•Deep learning models are useful tools to assist decision making in reservoir operation.•The long short-term memory model is suitable for reservoir outflow predictions.•Different parameterizations ...are tested to verify the performance of different models.
Reservoirs and dams are vital human-built infrastructures that play essential roles in flood control, hydroelectric power generation, water supply, navigation, and other functions. The realization of those functions requires efficient reservoir operation, and the effective controls on the outflow from a reservoir or dam. Over the last decade, artificial intelligence (AI) techniques have become increasingly popular in the field of streamflow forecasts, reservoir operation planning and scheduling approaches. In this study, three AI models, namely, the backpropagation (BP) neural network, support vector regression (SVR) technique, and long short-term memory (LSTM) model, are employed to simulate reservoir operation at monthly, daily, and hourly time scales, using approximately 30 years of historical reservoir operation records. This study aims to summarize the influence of the parameter settings on model performance and to explore the applicability of the LSTM model to reservoir operation simulation. The results show the following: (1) for the BP neural network and LSTM model, the effects of the number of maximum iterations on model performance should be prioritized; for the SVR model, the simulation performance is directly related to the selection of the kernel function, and sigmoid and RBF kernel functions should be prioritized; (2) the BP neural network and SVR are suitable for the model to learn the operation rules of a reservoir from a small amount of data; and (3) the LSTM model is able to effectively reduce the time consumption and memory storage required by other AI models, and demonstrate good capability in simulating low-flow conditions and the outflow curve for the peak operation period.
Bacterial RNA polymerase employs extra-cytoplasmic function (ECF) σ factors to regulate context-specific gene expression programs. Despite being the most abundant and divergent σ factor class, the ...structural basis of ECF σ factor-mediated transcription initiation remains unknown. Here, we determine a crystal structure of Mycobacterium tuberculosis (Mtb) RNAP holoenzyme comprising an RNAP core enzyme and the ECF σ factor σ
(σ
-RNAP) at 2.7 Å, and solve another crystal structure of a transcription initiation complex of Mtb σ
-RNAP (σ
-RPo) comprising promoter DNA and an RNA primer at 2.8 Å. The two structures together reveal the interactions between σ
and RNAP that are essential for σ
-RNAP holoenzyme assembly as well as the interactions between σ
-RNAP and promoter DNA responsible for stringent promoter recognition and for promoter unwinding. Our study establishes that ECF σ factors and primary σ factors employ distinct mechanisms for promoter recognition and for promoter unwinding.
Abstract
Oncogenic activation of KRAS and its surrogates is essential for tumour cell proliferation and survival, as well as for the development of protumourigenic microenvironments. Here, we show ...that the deubiquitinase USP12 is commonly downregulated in the
Kras
G12D
-driven mouse lung tumour and human non-small cell lung cancer owing to the activation of AKT-mTOR signalling. Downregulation of USP12 promotes lung tumour growth and fosters an immunosuppressive microenvironment with increased macrophage recruitment, hypervascularization, and reduced T cell activation. Mechanistically, USP12 downregulation creates a tumour-promoting secretome resulting from insufficient PPM1B deubiquitination that causes NF-κB hyperactivation in tumour cells. Furthermore, USP12 inhibition desensitizes mouse lung tumour cells to anti-PD-1 immunotherapy. Thus, our findings propose a critical component downstream of the oncogenic signalling pathways in the modulation of tumour-immune cell interactions and tumour response to immune checkpoint blockade therapy.
PDF