The nitrogenous nucleophile electrooxidation reaction (NOR) plays a vital role in the degradation and transformation of available nitrogen. Focusing on the NOR mediated by the β‐Ni(OH)2 electrode, we ...decipher the transformation mechanism of the nitrogenous nucleophile. For the two‐step NOR, proton‐coupled electron transfer (PCET) is the bridge between electrocatalytic dehydrogenation from β‐Ni(OH)2 to β‐Ni(OH)O, and the spontaneous nucleophile dehydrogenative oxidation reaction. This theory can give a good explanation for hydrazine and primary amine oxidation reactions, but is insufficient for the urea oxidation reaction (UOR). Through operando tracing of bond rupture and formation processes during the UOR, as well as theoretical calculations, we propose a possible UOR mechanism whereby intramolecular coupling of the N−N bond, accompanied by PCET, hydration and rearrangement processes, results in high performance and ca. 100 % N2 selectivity. These discoveries clarify the evolution of nitrogenous molecules during the NOR, and they elucidate fundamental aspects of electrocatalysis involving nitrogen‐containing species.
During urea electrooxidation over a Ni(OH)2 electrode the dehydrogenation reaction from β‐Ni(OH)2 to β‐Ni(OH)O can lead to spontaneous urea dehydrogenation. Spontaneous intramolecular coupling of the N−N bond and hydration of urea dehydrogenation intermediates play important roles in the oxidation path from urea to N2 and CO2.
The use of nitrogen fertilizers has been estimated to have supported 27% of the world’s population over the past century. Urea (CO(NH2)2) is conventionally synthesized through two consecutive ...industrial processes, N2 + H2 → NH3 followed by NH3 + CO2 → urea. Both reactions operate under harsh conditions and consume more than 2% of the world’s energy. Urea synthesis consumes approximately 80% of the NH3 produced globally. Here we directly coupled N2 and CO2 in H2O to produce urea under ambient conditions. The process was carried out using an electrocatalyst consisting of PdCu alloy nanoparticles on TiO2 nanosheets. This coupling reaction occurs through the formation of C–N bonds via the thermodynamically spontaneous reaction between *N=N* and CO. Products were identified and quantified using isotope labelling and the mechanism investigated using isotope-labelled operando synchrotron-radiation Fourier transform infrared spectroscopy. A high rate of urea formation of 3.36 mmol g–1 h–1 and corresponding Faradic efficiency of 8.92% were measured at –0.4 V versus reversible hydrogen electrode.Conventionally, urea is synthesized via two consecutive processes, N2 + H2 → NH3 followed by NH3 + CO2. Now, an electrocatalyst consisting of PdCu alloy nanoparticles on TiO2 nanosheets has been shown to directly couple N2 and CO2 in H2O to produce urea under ambient conditions.
Quality control can decrease variations in the performance of colonoscopists and improve the effectiveness of colonoscopy to prevent colorectal cancers. Unfortunately, routine quality control is ...difficult to carry out because a practical method is lacking. The aim of this study was to develop an automatic quality control system (AQCS) and assess whether it could improve polyp and adenoma detection in clinical practice.
First, we developed AQCS based on deep convolutional neural network models for timing of the withdrawal phase, supervising withdrawal stability, evaluating bowel preparation, and detecting colorectal polyps. Next, consecutive patients were prospectively randomized to undergo routine colonoscopies with or without the assistance of AQCS. The primary outcome of the study was the adenoma detection rate (ADR) in the AQCS and control groups.
A total of 659 patients were enrolled and randomized. A total of 308 and 315 patients were analyzed in the AQCS and control groups, respectively. AQCS significantly increased the ADR (0.289 vs 0.165, P < .001) and the mean number of adenomas per procedure (0.367 vs 0.178, P < .001) compared with the control group. A significant increase was also observed in the polyp detection rate (0.383 vs 0.254, P = .001) and the mean number of polyps detected per procedure (0.575 vs 0.305, P < .001). In addition, the withdrawal time (7.03 minutes vs 5.68 minutes, P < .001) and adequate bowel preparation rate (87.34% vs 80.63%, P = .023) were superior for the AQCS group.
AQCS could effectively improve the performance of colonoscopists during the withdrawal phase and significantly increase polyp and adenoma detection. (Clinical trial registration number: NCT03622281.)
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This paper investigates the sum-capacity of two-user optical intensity multiple access channels with per-user peak- or/and average-intensity constraints. By leveraging tools from the decomposition of ...certain distributions, we derive several lower bounds on the sum-capacity. In the high signal-to-noise ratio (SNR) regime, some bounds asymptotically match or approach the sum-capacity, thus closing or reducing the existing gaps to the high-SNR asymptotic sum-capacity. At moderate SNR, some bounds are also fairly close to the sum-capacity.
Alternate-day fasting (ADF) is a novel diet therapy that may achieve reduction in body weight and improvement of dyslipidaemia, but the impact of this diet on patients with non-alcoholic fatty liver ...disease (NAFLD) remains unknown. The aim of this study was to evaluate the effects of ADF on the body weight and lipid profile of individuals with NAFLD.
NAFLD patients (n = 271) were randomised to the ADF group, time-restricted feeding (TRF) group, or the control group and subjected to the respective diet for 12 weeks. Anthropometric measurements (body weight, fat mass/fat-free mass) were performed, and plasma lipids were analysed enzymatically.
Within 4 weeks, the body weight decreased significantly (P < 0.001) in the ADF group by 4.56 ± 0.41 kg (6.1 ± 0.5%) and the TRF group by 3.62 ± 0.65 kg (4.83 ± 0.9%) compared to the control group, and it decreased even more after 12 weeks in both groups (ADF: - 4.04 ± 0.54 kg, 5.4 ± 0.7%; TRF: - 3.25 ± 0.67 kg, 4.3 ± 0.9%). Fat mass was significantly reduced by ADF (- 3.49 ± 0.37 kg; 11 ± 1.2%) and TRF (- 2.91 ± 0.41 kg; 9.6 ± 1.3%), with ADF leading to a further reduction in fat mass after 12 weeks (- 3.48 ± 0.38 kg; 11 ± 1.2%). Total cholesterol was significantly decreased at both time points in the ADF group (- 0.91 ± 0.07 mmol/L; 18.5 ± 1.5%) compared to the control and TRF groups. Both ADF (- 0.64 ± 0.06 mmol/L; 25 ± 1.9%) and TRF (0.58 ± 0.07 mmol/L; 20 ± 1.7%) achieved a significant reduction in serum triglycerides (P < 0.001) after 12 weeks. Changes in fat free mass, HDL, LDL, fasting insulin, glucose, liver stiffness, and systolic or diastolic blood pressure did not differ between the groups.
ADF appears to be an effective diet therapy for individuals with NAFLD that can achieve weight loss and improvement of dyslipidaemia within a relatively short period of time (4 to 12 weeks). Potential preventive effects of ADF on cardiovascular disease need to be confirmed by future investigations.
ChiCTR1900024411, this trial was retrospectively registered on July 10, 2019.
Background
Breast cancer is the most commonly diagnosed cancer and leading cause of cancer death among women worldwide but has patterns and trends which vary in different countries. This study aimed ...to evaluate the global patterns of breast cancer incidence and mortality and analyze its temporal trends for breast cancer prevention and control.
Methods
Breast cancer incidence and mortality data in 2020 were obtained from the GLOBOCAN online database. Continued data from the Cancer Incidence in Five Continents Time Trends, the International Agency for Research on cancer mortality and China National Central Cancer Registry were used to analyze the time trends from 2000 to 2015 through Joinpoint regression, and annual average percent changes of breast cancer incidence and mortality were calculated. Association between Human Development Index and breast cancer incidence and mortality were estimated by linear regression.
Results
There were approximately 2.3 million new breast cancer cases and 685,000 breast cancer deaths worldwide in 2020. Its incidence and mortality varied among countries, with the age‐standardized incidence ranging from the highest of 112.3 per 100,000 population in Belgium to the lowest of 35.8 per 100,000 population in Iran, and the age‐standardized mortality from the highest of 41.0 per 100,000 population in Fiji to the lowest of 6.4 per 100,000 population in South Korea. The peak age of breast cancer in some Asian and African countries were over 10 years earlier than in European or American countries. As for the trends of breast cancer, the age‐standardized incidence rates significantly increased in China and South Korea but decreased in the United States of America (USA) during 2000‐2012. Meanwhile, the age‐standardized mortality rates significantly increased in China and South Korea but decreased in the United Kingdom, the USA, and Australia during 2000 and 2015.
Conclusions
The global burden of breast cancer is rising fast and varies greatly among countries. The incidence and mortality rates of breast cancer increased rapidly in China and South Korea but decreased in the USA. Increased health awareness, effective prevention strategies, and improved access to medical treatment are extremely important to curb the snowballing breast cancer burden, especially in the most affected countries.
Cancer-associated fibroblasts cells (CAFs) confer a rapid growth and metastasis ability of endometrial cancer (EC) via exosomes-mediated cellular communication. Long non-coding RNA nuclear enriched ...abundant transcript 1 (lncRNA NEAT1) drives the malignant phenotypes of EC cells. However, the role of exosomal NEAT1 from CAFs in EC progression remains ambiguous, which needs to be investigated. In our study, NEAT1 and YKL-40 were up-regulated, while miR-26a/b-5p was down-regulated in EC tissues. Moreover, NEAT1 expression was increased in CAF-exosomes compared with that in NF-exosomes. In addition, the exosomal NEAT1 derived from CAFs could transfer to EC cells and promote YKL-40 expression. Further exploration showed that exosomal NEAT1 enhanced YKL-40 expression via regulating miR-26a/b-5p-STAT3 axis in EC cells. More importantly, exosomal NEAT1 accelerated in vivo tumor growth via miR-26a/b-5p-STAT3-YKL-40 axis. Taken together, our study reveals that exosomal NEAT1 from CAFs contributes to EC progression via miR-26a/b-5p-mediated STAT3/YKL-40 pathway, which indicates the therapeutic potential of exosomal NEAT1 for treating EC.
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Interest in piezochromic luminescence has increased in recent decades, even though it is mostly limited to pure organic compounds and fluorescence. In this work, a Cu
3
Pz
3
(
Cu
3
, Pz: pyrazolate) ...cyclic trinuclear complex (CTC) with two different crystalline polymorphs, namely
1a
and
1b
, was synthesized. The CTC consists of two functional moieties: carbazole (
Cz
) chromophore and
Cu
3
units. In crystals of
1a
, discrete
Cz
-
Cu
3
-
Cu
3
-
Cz
stacking was found, showing abnormal pressure-induced phosphorescence enhancement (PIPE), which was 12 times stronger at 2.23 GPa compared to under ambient conditions. This novel observation is ascribed to cooperation between heavy-atom effects (
i.e.
, from Cu atoms) and metal-ligand charge-transfer promotion. The infinite π-π stacking of
Cz
motifs was observed in
1b
and it exhibited good piezochromism as the pressure increased. This work demonstrates a new concept in the design of piezochromic materials to achieve PIPE
via
combining organic chromophores and metal-organic phosphorescence emitters.
One molecule, two response mechanisms: a pair of newly-designed cyclic trinuclear Cu(
i
) complex crystalline polymorphs are engineered, which show excellent luminescent piezochromism and pressure-induced phosphorescence enhancement, respectively.
Background and aims
Endoscopic diagnosis of early esophageal squamous cell cancer (ESCC) is complicated and dependent on operators' experience. This study aimed to develop an artificial intelligence ...(AI) model for automatic diagnosis of early ESCC.
Methods
Non‐magnifying and magnifying endoscopic images of normal/noncancerous lesions, early ESCC, and advanced esophageal cancer (AEC) were retrospectively obtained from Qilu Hospital of Shandong University. A total of 10,988 images from 5075 cases were chosen for training and validation. Another 2309 images from 1055 cases were collected for testing. One hundred and four real‐time videos were also collected to evaluate the diagnostic performance of the AI model. The diagnostic performance of the AI model was compared with endoscopists by magnifying images and the assistant efficiency of the AI model for novices was evaluated.
Results
The AI diagnosis for non‐magnifying images showed a per‐patient accuracy, sensitivity, and specificity of 99.5%, 100%, 99.5% for white light imaging, and 97.0%, 97.2%, 96.4% for optical enhancement/iodine straining images. Regarding diagnosis for magnifying images, the per‐patient accuracy, sensitivity, and specificity were 88.1%, 90.9%, and 85.0%. The diagnostic accuracy of the AI model was similar to experts (84.5%, P = 0.205) and superior to novices (68.5%, P = 0.005). The diagnostic performance of novices was significantly improved by AI assistance. When it comes to the diagnosis for real‐time videos, the AI model showed acceptable performance as well.
Conclusions
The AI model could accurately recognize early ESCC among noncancerous mucosa and AEC. It could be a potential assistant for endoscopists, especially for novices.
Black phosphorus (BP) has recently aroused researchers’ great interest as promising anode material for sodium-ion battery (SIB), owing to its high theoretical capacity (2596 mAh g–1) and good ...electric conductivity (about 300 S m–1). However, the large volume variation during electrochemical cycling makes it difficult to use for practical applications. Herein, the reversible performance of BP in SIB is significantly enhanced by bridging covalently functionalized BP on graphene. The enhanced interaction between the chemical functionalized BP and graphene improves the stability of BP during long-cycle running of SIB. The bridging reduces the surface energy and increases thickness of BP available for enlarging the channel between BP nanosheet and graphene. The enlarged channel stores more sodium ions for improving cycle performance. Significantly, two types of phosphorus–carbon bond are first detected during experimental analysis. Benefiting from the strategy, the BP-based SIB anode exhibits 1472 mAh g–1 specific capacity at 0.1 A g–1 in the 50th cycle and 650 mAh g–1 at 1 A g–1 after 200 cycles.
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