Harvesting heat from the environment into electricity has the potential to power Internet-of-Things (IoT) sensors, freeing them from cables or batteries especially for use as wearable devices. We ...demonstrate a giant positive thermopower of 17.0 mV K
in a flexible, quasi-solid state, ionic thermoelectric material using synergistic thermodiffusion and thermogalvanic effects. The ionic thermoelectric material is a gelatin matrix modulated with ions providers (KCl, NaCl, and KNO
) for thermodiffusion effect and redox couple (Fe(CN)
/Fe(CN)
) for thermogalvanic effect. A proof-of-concept wearable device consisting of 25 unipolar elements generated over 2 V and a peak power of 5 μW using body heat. This ionic gelatin shows promises for environmental heat-to-electric energy conversion utilizing ions as energy carriers.
Electrochemical reduction of nitrite addresses the need for nitrite contaminant removal and provides an on-site, cost-effective, and sustainable route for rapidly generating ammonia/ammonium. Its ...practical implementation however requires advanced electrocatalysts with enhanced ammonium yield rates and faradaic efficiencies. Our study here introduces a Cu3P nanowire array supported on copper foam (Cu3P NA/CF) for the first time as an efficient electrocatalyst for nitrite-to-ammonium conversion in neutral media. In 0.1 M phosphate buffered saline containing 0.1 M NaNO2, the freestanding Cu3P NA/CF electrode displays a large ammonium yield rate of 1626.6 ± 36.1 μg h−1 cm−2 and a high FE of 91.2 ± 2.5% at −0.5 V vs. a reversible hydrogen electrode, with good stability. The catalytic mechanism is revealed by density functional theory calculations.
Developing non-noble-metal oxygen evolution reaction (OER) electrocatalysts with high performance is critical to electrocatalytic water splitting. In this work, we fabricated CoFe-layered double ...hydroxide (LDH) nanowire arrays on graphite felt (CoFe-LDH/GF) via a hydrothermal method. The CoFe-LDH/GF, as a robust integrated 3D OER anode, exhibits excellent catalytic activity with the need of low overpotential of 252 and 285 mV to drive current densities of 10 and 100 mA/cm2 in 1.0 mol/L KOH, respectively. In addition, it also maintains electrochemical durability for at least 24 h. This work would open up avenues for the development of GF like attractive catalyst supports for oxygen evolution applications.
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CoFe-LDH nanowire arrays on graphite felt acts as a superb oxygen evolution catalyst with high durability and low overpotential of 252 and 285 mV to attain 10 and 100 mA/cm2 in 1.0 mol/L KOH, respectively.
While it is known that miR-203 is frequently downregulated in many types of human cancer, little is known regarding its expression and functional role in colorectal cancer (CRC). In this study, we ...aimed to investigate the expression and the potential mechanisms of miR-203 in colorectal cancer. MiR-203 was significantly downregulated in CRC tissues compared with matched normal adjacent tissues. Our clinical data show that decreased miR-203 was associated with an advanced clinical tumor-node-metastasis stage, lymph node metastasis, and poor survival in CRC patients. Furthermore, externally induced expression of miR-203 significantly inhibited CRC cell proliferation and invasion in vitro and in vivo. Mechanistically, we identified EIF5A2 as a direct and functional target of miR-203. The levels of miR-203 were inversely correlated with levels of the EIF5A2 in the CRC tissues. Restoration of EIF5A2 in the miR-203-overexpressing CRC cells reversed the suppressive effects of miR-203. Our results demonstrate that miR-203 serves as a tumor suppressor gene and may be useful as a new potential therapeutic target in CRC.
Hydrogen is a promising carbon-free fuel, but nitric oxides (NOx) emissions are significantly increased with higher temperature in hydrogen combustion. Internal flue gas recirculation (IFGR) is one ...of the most effective NOx reduction techniques in boilers. Previous research has widely reported NOx generation with hydrogen enrichments from a chemical kinetic perspective, however, the NOx formation principles in non-premixed methane/air combustion using IFGR with hydrogen addition are still unclear. This work aims to investigate the effects of hydrogen addition on NOx formation in a non-premixed methane low-NOx combustor using IFGR. The Reynolds-averaged Navier-Stokes (RANS) simulations were conducted on a 5 kW non-premixed combustor with IFGR rate of 17.7%, which generated 11.3 mg/m3 of total NOx generation in methane combustion. A series of three-dimensional computational fluid dynamics (CFD) simulations with detailed mechanisms was tested on four hydrogen power fractions. The reaction intensities of the main NOx formation pathways were analyzed on reaction rates. The results show that 70% hydrogen power fractions lead to significantly greater NOx concentration to 677.8 mg/m3, as high as 60 times of the original concentration. With no additional techniques, the original methane low-NOx combustor is only allowed for hydrogen addition of less than 20% power fraction. The NNH route becomes the second dominant pathway in hydrogen-added flames. Influenced by the growing hydrogen contents, the generation of the NNH route is largely generated from 2 mg/m3 to 65 mg/m3. This work connects the hydrogen addition and the NOx formation pathways in non-premixed methane combustion, and highlights the importance of eliminating thermal NOx and the NNH route to achieve low-NOx combustion rather than sole NOx suppression method, which can provide a reference for designing low-NOx techniques.
A single-layer, planar wideband microstrip line (ML) fed metasurface-based antenna operating at 5 GHz wireless local area network band is proposed. It is composed of an array of ...<inline-formula><tex-math notation="LaTeX">3 \times 3</tex-math></inline-formula> square metal patches fed by an ML connected to the central patch of the three peripheral unit cells. To reduce the phase delay between the driven patch and the parasitic patches placed along the E -plane, a large square slot is cut on the fed patch, while the patches on the second and third rows are sliced into smaller ones to stabilize the patterns at higher frequencies. The large slot also helps achieve better impedance matching. <inline-formula><tex-math notation="LaTeX">{{\bf T}}{{{\bf M}}_{01}}</tex-math></inline-formula> and <inline-formula><tex-math notation="LaTeX">{{\bf T}}{{{\bf M}}_{21}}</tex-math></inline-formula> modes are excited, giving a measured <inline-formula><tex-math notation="LaTeX"> - 10{\boldsymbol{\ }}{{\bf dB}}</tex-math></inline-formula> bandwidth of 26.56% (5.06-6.61 GHz). The compact size of <inline-formula><tex-math notation="LaTeX">1{{\boldsymbol{\lambda }}_0} \times 1.1{{\boldsymbol{\lambda }}_0} \times 0.058{{\boldsymbol{\lambda }}_0}</tex-math></inline-formula> (<inline-formula><tex-math notation="LaTeX">{{\boldsymbol{\lambda }}_0}</tex-math></inline-formula> is the free-space wavelength at the center of the frequency band), stable boresight patterns, low profile, planar configuration, and wide bandwidth features make the presented antenna attractive for various wireless systems.
The inherently small temperature difference in air environment restricts the applications of thermoelectric generation in the field of Internet of Things and wearable electronics. Here, a ...leaf‐inspired flexible thermoelectric generator (leaf‐TEG) that makes maximum use of temperature difference by vertically aligning poly(3,4‐ethylenedioxythiophene) polystyrene sulfonate and constantan thin films is demonstrated. Analytical formulae of the performance scales, i.e., temperature difference utilization ratio (φth) and maximum output power (Pmax), are derived to optimize the leaf‐TEG dimensions. In an air duct (substrate: 36 °C, air: 6 °C, air flowing: 1 m s−1), the 10‐leaf‐TEG shows a φth of 73% and Pmax of 0.38 µW per leaf. A proof‐of‐concept wearable 100‐leaf‐TEG (60 cm2) generates 11 µW on an arm at room temperature. Furthermore, the leaf‐TEG is flexible and durable that is confirmed by bending and brushing over 1000 times. The proposed leaf‐TEG is very appropriate for air convection scenarios with limited temperature differences.
A leaf‐structure thin film‐based flexible thermoelectric generator (leaf‐TEG), structure similar to fins, enhances the temperature difference utilization ratio (φth) of up to 85% with a rapid response to air temperature fluctuations. Thus opening the path to the development of highly efficient output under limited temperature difference conditions for the flexible TEG field.
Ferroelectric polymers have great potential applications in mechanical/thermal sensing, but their sensitivity and detection limit are still not outstanding. We propose interface engineering to ...improve the charge collection in a ferroelectric poly(vinylidene fluoride-co-trifluoroethylene) copolymer (P(VDF-TrFE)) thin film via cross-linking with poly(3,4-ethylenedioxythiophene) doped with polystyrenesulfonate (PEDOT:PSS) layer. The as-fabricated P(VDF-TrFE)/PEDOT:PSS composite film exhibits an ultrasensitive and linear mechanical/thermal response, showing sensitivities of 2.2 V kPa
in the pressure range of 0.025-100 kPa and 6.4 V K
in the temperature change range of 0.05-10 K. A corresponding piezoelectric coefficient of -86 pC N
and a pyroelectric coefficient of 95 μC m
K
are achieved because more charge is collected by the network interconnection interface between PEDOT:PSS and P(VDF-TrFE), related to the increase in the dielectric properties. Our work shines a light on a device-level technique route for boosting the sensitivity of ferroelectric polymer sensors through electrode interface engineering.
Abstract
Background
Lung adenocarcinoma (LUAD) is a leading cause of cancer-related death worldwide. Ferroptosis, a form of cell death characterized by iron-dependent lipid peroxidation. However, the ...involvement of ferroptosis in the regulation of immune cell infiltration and its immunotherapeutic efficacy in LUAD remain unclear.
Methods
The Cancer Genome Atlas (TCGA) LUAD cohort was used to assess the survival prognosis of FRGs and construct a seven-gene risk signature. Correlation tests, difference tests, and a cluster analysis were performed to explore the role of FRGs in the immune microenvironment and their immunotherapeutic efficacy in LUAD. The effects of FRGs on LUAD cells were assessed by Western blot, iron assay, and lipid peroxidation assay.
Results
The seven-gene risk signatures of patients with LUAD were established and validated. FRG clustering based on 70 differentially expressed FRGs was associated with the immune microenvironment and indicated potential immune subtypes of LUAD. The seven-gene risk signature was an independent prognostic factor for LUAD and was used to divide the LUAD cohort into a high-risk and a low-risk group. Immunocyte infiltration levels, immune checkpoints, and immunotherapy response rates were significantly different between the two groups. Patients with high risk scores had lower overall levels of immunocyte infiltration but higher immunotherapy response rates. The key gene ribonucleotide reductase subunit M2 (RRM2) was associated with LUAD prognosis, which may be related to its ability to regulate the infiltration levels of activated mast cells and activated CD4 memory T cells. In addition, RRM2 was involved in ferroptosis, and its expression was up regulated in lung cancer tissues and the LUAD cell lines. Silencing RRM2 can inhibit the proliferation and induce ferroptosis of H1975 cells suggesting that silencing RRM2 could promote ferroptosis in H1975 cells.
Conclusion
Our results revealed RRM2 as a promising biomarker and therapeutic target associated with tumor immune infiltration in patients with LUAD.
This communication presents a novel single-layer, low-profile broadband metasurface (MTS)-inspired antenna with monopole-like radiation characteristics. To excite symmetric surface waves propagating ...along an MTS consisting of an array of 4 × 4 metal square patches, a horizontal center-fed monopole structure is used at the center of the MTS. The proposed antenna is further embedded within a square ring to improve the gain and H-plane patterns roundness at the upper-frequency band. The presented antenna achieved a -10 dB bandwidth of 32.62% (5.08-7.06 GHz) and a low-profile of 0.06λ0(λ0 is the free space wavelength at the center of the operating band) distinctive features due, respectively, to the effective excitation of different TM surface wave resonant modes that are close to each other and the in-phase reflection property of the MTS. The planar structure, single-layer, and low-profile merits make the proposed antenna an ideal candidate for various wireless communications systems, such as wireless local area network (WLAN) at 5.2/5.8 GHz, WiMAX at 5.5 GHz, and car to car (C2C) at 5.85-5.925 GHz.
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