Designing stable single-atom electrocatalysts with lower energy barriers is urgent for the acidic oxygen evolution reaction. In particular, the atomic catalysts are highly dependent on the ...kinetically sluggish acid–base mechanism, limiting the reaction paths of intermediates. Herein, we successfully manipulate the steric localization of Ru single atoms at the Co3O4 surface to improve acidic oxygen evolution by precise control of the anchor sites. The delicate structure design can switch the reaction mechanism from the lattice oxygen mechanism (LOM) to the optimized adsorbate evolution mechanism (AEM). In particular, Ru atoms embedded into cation vacancies reveal an optimized mechanism that activates the proton donor–acceptor function (PDAM), demonstrating a new single-atom catalytic pathway to circumvent the classic scaling relationship. Steric interactions with intermediates at the anchored Ru–O–Co interface played a primary role in optimizing the intermediates’ conformation and reducing the energy barrier. As a comparison, Ru atoms confined to the surface sites exhibit a lattice oxygen mechanism for the oxygen evolution process. As a result, the delicate atom control of the spatial position presents a 100-fold increase in mass activity from 36.96 A gRu(ads) –1 to 4012.11 A gRu(anc) –1 at 1.50 V. These findings offer new insights into the precise control of single-atom catalytic behavior.
Increasing awareness of climate change and food security has spawned an interest in low-carbon agriculture, an important aspect of which is the reduction of greenhouse gas emissions. As the largest ...source of agricultural emissions is fertilizer application, using a different type of fertilizer may help to mitigate greenhouse gas emissions from agriculture systems. The objectives of this study were to report a basic estimate of agricultural inputs and greenhouse gas emissions of crop production using national statistical data available for the period of 1993–2007, to compare the quantities of greenhouse gas emissions from different fertilizer types (per unit of N, P2O5, and K2O), to identify fertilizer types with the lowest emissions and the lowest costs, and to quantify the emissions gap between the lowest and actual emission scenarios, which will provide critical information for pursuing low-carbon agriculture in the future. According to available data, the use of all agricultural inputs increased during 1993–2012, resulting in an increase in not only yield but also in total greenhouse gas emissions from crop production. Not considering direct N2O emissions from the field, fertilizer-induced emissions accounted for up to 47.71% of the total greenhouse gas emissions from crop production. Therefore, lowering fertilizer-induced emissions is a priority measure that will result in low-carbon agriculture. Furthermore, ammonium bicarbonate, calcium superphosphate, and potassium chloride were found to be fertilizers with the lowest greenhouse gas emissions, and adoption of these fertilizers would result in a 49.15% reduction in fertilizer-induced emissions. This finding indicates that the judicious choice of fertilizer type would contribute to reducing greenhouse gas emissions in intensive production systems in China. Accordingly, utilizing ammonium bicarbonate, calcium superphosphate, and potassium chloride would be beneficial for greenhouse gas emission reduction and could be adopted as a good practice of low-carbon agriculture in China. This study highlights that changing to an appropriate fertilizer type could be an efficient option for mitigating greenhouse gas emissions in crop production in China.
•GHG emissions from different types of fertilizer products were compared.•The lowest emissions of the N, P, and K fertilizers were identified, respectively.•Adoption of the lowest emissions result in a 49% reduction of fertilizer emissions.
Platelet-rich plasma (PRP) is prepared by centrifuging fresh blood in an anticoagulant state, and harvesting the platelet-rich portion or condensing platelets. Studies have consistently demonstrated ...that PRP concentrates are an abundant source of growth factors, such as platelet-derived growth factor (PDGF), transforming growth factor β (TGF-β), insulin-like growth factor 1 (IGF-1), and epithelial growth factor (EGF). The complex mechanisms underlying spinal cord injury (SCI) diminish intrinsic repair and neuronal regeneration. Several studies have suggested that growth factor-promoted axonal regeneration can occur for an extended period after injury. More importantly, the delivery of exogenous growth factors contained in PRP, such as EGF, IGF-1, and TGF-β, has neurotrophic effects on central nervous system (CNS) injuries and neurodegenerative diseases. However, only a few studies have investigated the effects of PRP on CNS injuries or neurodegenerative diseases. According to our review of relevant literature, no study has investigated the effect of intrathecal (i.t.) PRP injection into the injured spinal cord and activation of intrinsic mechanisms. In the present study, we directly injected i.t. PRP into rat spinal cords and examined the effects of PRP on normal and injured spinal cords. In rats with normal spinal cords, PRP induced microglia and astrocyte activation and PDGF-B and ICAM-1 expression. In rats with SCIs, i.t. PRP enhanced the locomotor recovery and spared white matter, promoted angiogenesis and neuronal regeneration, and modulated blood vessel size. Furthermore, a sustained treatment (a bolus of PRP followed by a 1/3 dose of initial PRP concentration) exerted more favorable therapeutic effects than a single dose of PRP. Our findings suggest by i.t. PRP stimulate angiogenesis, enhancing neuronal regeneration after SCI in rats. Although PRP induces minor inflammation in normal and injured spinal cords, it has many advantages. It is an autologous, biocompatible, nontoxic material that does not result in a major immune response. In addition, based on its safety and ease of preparation, we hypothesize that PRP is a promising therapeutic agent for SCI.
Partially fermented tea such as oolong tea is a popular drink worldwide. Preventing fraud in partially fermented tea has become imperative to protect producers and consumers from possible economic ...losses. Visible/near-infrared (VIS/NIR) spectroscopy integrated with stepwise multiple linear regression (SMLR) and support vector machine (SVM) methods were used for origin discrimination of partially fermented tea from Vietnam, China, and different production areas in Taiwan using the full visible NIR wavelength range (400–2498 nm). The SMLR and SVM models achieved satisfactory results. Models using data from chemical constituents’ specific wavelength ranges exhibited a high correlation with the spectra of teas, and the SMLR analyses improved discrimination of the types and origins when performing SVM analyses. The SVM models’ identification accuracies regarding different production areas in Taiwan were effectively enhanced using a combination of the data within specific wavelength ranges of several constituents. The accuracy rates were 100% for the discrimination of types, origins, and production areas of tea in the calibration and prediction sets using the optimal SVM models integrated with the specific wavelength ranges of the constituents in tea. NIR could be an effective tool for rapid, nondestructive, and accurate inspection of types, origins, and production areas of teas.
Methamphetamine abuse is getting worse amongst the younger population. While there is methadone or buprenorphine harm-reduction treatment for heroin addicts, there is no drug treatment for addicts ...with methamphetamine use disorder (MUD). Recently, non-medication treatment, such as the cue-elicited craving method integrated with biofeedback, has been widely used. Further, virtual reality (VR) is proposed to simulate an immersive virtual environment for cue-elicited craving in therapy. In this study, we developed a VR system equipped with flavor simulation for the purpose of inducing cravings for MUD patients in therapy. The VR system was integrated with multi-model sensors, such as an electrocardiogram (ECG), galvanic skin response (GSR) and eye tracking to measure various physiological responses from MUD patients in the virtual environment. The goal of the study was to validate the effectiveness of the proposed VR system in inducing the craving of MUD patients via the physiological data. Clinical trials were performed with 20 MUD patients and 11 healthy subjects. VR stimulation was applied to each subject and the physiological data was measured at the time of pre-VR stimulation and post-VR stimulation. A variety of features were extracted from the raw data of heart rate variability (HRV), GSR and eye tracking. The results of statistical analysis found that quite a few features of HRV, GSR and eye tracking had significant differences between pre-VR stimulation and post-VR stimulation in MUD patients but not in healthy subjects. Also, the data of post-VR stimulation showed a significant difference between MUD patients and healthy subjects. Correlation analysis was made and several features between HRV and GSR were found to be correlated. Further, several machine learning methods were applied and showed that the classification accuracy between MUD and healthy subjects at post-VR stimulation attained to 89.8%. In conclusion, the proposed VR system was validated to effectively induce the drug craving in MUD patients.
Twist, the basic helix-loop-helix transcription factor, is involved in the process of epithelial to mesenchymal transitions (EMTs), which play an essential role in cancer metastasis. Overexpression ...of Twist or its promoter methylation is a common scenario in metastatic carcinomas. Twist is activated by a variety of signal transduction pathways, including Akt, signal transducer and activator of transcription 3, mitogen-activated protein kinase, Ras, and Wnt signaling. Activated Twist upregulates N-cadherin and downregulates E-cadherin, which are the hallmarks of EMT. Moreover, Twist plays an important role in some physiological processes involved in metastasis, like angiogenesis, invadopodia, extravasation, and chromosomal instability. Twist also protects cancer cells from apoptotic cell death. In addition, Twist is responsible for the stemness of cancer cells and the generation of drug resistance. Recently, targeting Twist has gained significant interests in cancer therapeutics. The inactivation of Twist by small RNA technology or chemotherapeutic approach has been proved successful. Moreover, several inhibitors which are antagonistic to the upstream or downstream molecules of Twist signaling pathways have also been identified. Development of potential treatment strategies by targeting Twist has a great promise in cancer therapeutics.
The growing demand for bioelectronics has generated widespread interest in implantable energy storage. These implantable bioelectronic devices, powered by a complementary battery/capacitor system, ...have faced difficulty in miniaturization without compromising their functionality. This paper reports on the development of a promising high‐rate cathode material for implantable power sources based on Li‐exchanged Na1.5VOPO4F0.5 anchored on reduced graphene oxide (LNVOPF‐rGO). LNVOPF is unique in that it offers dual charge storage mechanisms, which enable it to exhibit mixed battery/capacitor electrochemical behavior. In this work, electrochemical Li‐ion exchange of the LNVOPF structure is characterized by operando X‐ray diffraction. Through designed nanostructuring, the charge storage kinetics of LNVOPF are improved, as reflected in the stored capacity of 107 mAh g−1 at 20C. A practical full cell device composed of LNVOPF and T‐Nb2O5, which serves as a pseudocapacitive anode, is fabricated to demonstrate not only high energy/power density storage (100 Wh kg−1 at 4000 W kg−1) but also reliable pulse capability and biocompatibility, a desirable combination for applications in biostimulating devices. This work underscores the potential of miniaturizing biomedical devices by replacing a conventional battery/capacitor couple with a single power source.
An implantable power source based on Li‐exchanged Na1.5VOPO4F0.5 anchored on reduced graphene oxide and Nb2O5 is developed to demonstrate not only high energy/power density storage (100 Wh kg−1 at 4000 W kg−1) but also reliable pulse capability and biocompatibility, a desirable combination for applications in biostimulating devices.
A green synthesis method is proposed for the preparation of nitrogen-doped multiporous carbons (denoted as N-MPCs) from water-caltrop shell (WCS) using eggshell waste as both a nitrogen-dopant and an ...activating agent. It is shown that the surface area, porosity, yield and nitrogen content of the as-prepared N-MPCs can be easily controlled by adjusting the activation temperature. Moreover, in oxygen reduction reaction (ORR) tests performed in O
2
-saturated 0.1 M KOH
(aq)
electrolyte containing 1.0 M methanol, the N-MPC catalysts show a high ORR stability and good resistance to methanol corrosion. In addition, as a cathode material in Al-air battery tests, the N-MPCs achieve a power density of 16 mW g
−1
in a saturated NaCl
(aq)
electrolyte. Overall, the results show that the N-MPCs have a promising potential as a green and sustainable material for ORR catalysis applications.
A green synthetic method is proposed for the preparation of nitrogen-doped multiporous carbons (denoted as N-MPCs) from water-caltrop-shell (WCS) biochar by using eggshell waste as both a nitrogen-dopant and an activating agent.
This study investigates wave height transformation caused by either a single high-crest or a series of low-crest submerged rectangular breakwaters through laboratory experiments and numerical ...simulations. The series configuration induces Bragg reflection without wave breaking, while the single breakwater leads to wave breaking. Numerical models, employing two-dimensional RANS equations coupled with the k-ε turbulence model, are validated against experimental data. The analysis encompasses wave height transformations, wave reflection and transmission coefficients, and the flow field linked to different breakwater arrangements. Results indicate that the four-breakwater series prominently demonstrates Bragg reflection, resulting in reduced transmission wave height. Conversely, the single high-crest submerged breakwater induces wave breaking, dissipating more turbulence energy and yielding a similar transmission wave height. Additionally, the wave run-up height on the rear slope behind breakwaters is lower in the single breakwater scenario under identical incident wave conditions.
•Compares wave height at single high-crest vs. series of low-crest breakwaters.•Four breakwaters exhibit Bragg reflection, significantly reducing transmission height.•Single breakwater induces wave breaking, resulting in similar transmission height.•Under identical wave conditions, run-up on the rear slope is lower in single breakwater.•Practical configurations inducing wave breaking may enhance coastal protection.
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