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The designed synthesis of a crystalline azulene-based covalent organic framework (COF-Azu-TP) is presented and its photothermal property is investigated. Azulene, a distinctive 5-7 fused ring non-benzenoid aromatic compound with a large intramolecular dipole moment and unique photophysical characteristics, is introduced as the key feature in COF-Azu-TP. The incorporation of azulene moiety imparts COF-Azu-TP with broad-spectrum light absorption capability and interlayer dipole interactions, which makes COF-Azu-TP a highly efficient photothermal conversion material. Its polyurethane (PU) composite exhibits a solar-to-vapor conversion efficiency (97.2%) and displays a water evaporation rate (1.43 kg m-2 h-1) under one sun irradiation, even at a very low dosage of COF-Azu-TP (2.2 wt%). Furthermore, COF-Azu-TP is utilized as a filler in a polylactic acid (PLA)/polycaprolactone (PCL) composited shape memory material, enabling rapid shape recovery under laser stimulation. A comparison study with a naphthalene-based COF isomer further emphasizes the crucial role of azulene in enhancing photothermal conversion efficiency. This study demonstrates the significance of incorporating specific building blocks into COFs for the development of functional porous materials with enhanced properties, paving the way for future applications in diverse fields.
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With the rapid development of micro/nano machining, there is an elevated demand for high-performance microdevices with high reliability and low cost. Due to their outstanding electrochemical, optical, electrical, and mechanical performance, carbon materials are extensively utilized in constructing microdevices for energy storage, sensing, and optoelectronics. Carbon micro/nano machining is fundamental in carbon-based intelligent microelectronics, multifunctional integrated microsystems, high-reliability portable/wearable consumer electronics, and portable medical diagnostic systems. Despite numerous reviews on carbon materials, a comprehensive overview is lacking that systematically encapsulates the development of high-performance microdevices based on carbon micro/nano structures, from structural design to manufacturing strategies and specific applications. This review focuses on the latest progress in carbon micro/nano machining toward miniaturized device, including structural engineering, large-scale fabrication, and performance optimization. Especially, the review targets an in-depth evaluation of carbon-based micro energy storage devices, microsensors, microactuators, miniaturized photoresponsive and electromagnetic interference shielding devices. Moreover, it highlights the challenges and opportunities in the large-scale manufacturing of carbon-based microdevices, aiming to spark further exciting research directions and application prospectives.
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We introduce a notion of local level spacings and study their statistics within a random-matrix-theory approach. In the limit of infinite-dimensional random matrices, we determine universal sequences of mean local spacings and of their ratios which uniquely identify the global symmetries of a quantum system and its internal-chaotic or regular-dynamics. These findings, which offer a new framework to monitor single- and many-body quantum systems, are corroborated by numerical experiments performed for zeros of the Riemann zeta function, spectra of irrational rectangular billiards, and many-body spectra of the Sachdev-Ye-Kitaev Hamiltonians.
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Complex morphologies in nature often arise from the assembly of elemental building blocks, leading to diverse and intricate structures. Understanding the mechanisms that govern the formation of these complex morphologies remains a significant challenge. In particular, the edge-base plate growth of biogenic crystals plays a crucial role in directing the development of intricate bioskeleton morphologies. However, the factors and regulatory processes that govern edge-base plate growth remain insufficiently understood. Inspired by biological skeletons and based on the soluble property of boric acid (BA) in both water and alcohols, we obtained a series of novel BA morphologies, including coccolith, and anemone biological skeletons. Here, we unveil the "inscribed circle effect", a concise mathematical model that reveals the underlying causative factors and regulatory mechanisms driving edge-base plate growth. Our findings illuminate how variations in solvent environments can exert control over the edge-base plate growth pathways, thereby resulting in the formation of diverse and complex morphologies. This understanding holds significant potential for guiding the chemical synthesis of bioskeleton materials.
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BACKGROUND: Early and appropriate antibiotic treatment improves the clinical outcome of patients with sepsis. There is an urgent need for rapid identification (ID) and antimicrobial susceptibility testing (AST) of bacteria that cause bloodstream infection (BSI). Rapid ID and AST can be achieved by short-term incubation on solid medium of positive blood cultures using MALDI-TOF mass spectrometry (MS) and the BD M50 system. The purpose of this study is to evaluate the performance of rapid method compared to traditional method. METHODS: A total of 124 mono-microbial samples were collected. Positive blood culture samples were short-term incubated on blood agar plates and chocolate agar plates for 5 â¼ 7 h, and the rapid ID and AST were achieved through Zybio EXS2000 MS and BD M50 System, respectively. RESULTS: Compared with the traditional 24 h culture for ID, this rapid method can shorten the cultivation time to 5 â¼ 7 h. Accurate organism ID was achieved in 90.6% of Gram-positive bacteria (GP), 98.5% of Gram-negative bacteria (GN), and 100% of fungi. The AST resulted in the 98.5% essential agreement (EA) and 97.1% category agreements (CA) in NMIC-413, 99.4% EA and 98.9% CA in PMIC-92, 100% both EA and CA in SMIC-2. Besides, this method can be used for 67.2% (264/393) of culture bottles during routine work. The mean turn-around time (TAT) for obtaining final results by conventional method is approximately 72.6 ± 10.5 h, which is nearly 24 h longer than the rapid method. CONCLUSIONS: The newly described method is expected to provide faster and reliable ID and AST results, making it an important tool for rapid management of blood cultures (BCs). In addition, this rapid method can be used to process most positive blood cultures, enabling patients to receive rapid and effective treatment.
Subject(s)
Bacteria , Microbial Sensitivity Tests , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization , Humans , Microbial Sensitivity Tests/methods , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/methods , Bacteria/drug effects , Bacteria/isolation & purification , Anti-Bacterial Agents/pharmacology , Fungi/drug effects , Fungi/isolation & purification , Blood Culture/methods , Gram-Negative Bacteria/drug effects , Gram-Negative Bacteria/isolation & purification , Time Factors , Gram-Positive Bacteria/drug effects , Gram-Positive Bacteria/isolation & purification , Sepsis/microbiology , Sepsis/drug therapy , Sepsis/diagnosisABSTRACT
BACKGROUND: This case involves a 28-year-old pregnant woman (39w+2) who was admitted to obstetrics due to abdominal tightness and bacteremia with Gardnerella vaginalis which developed after caesarean section and vaginal myomectomy. METHODS: A blood culture was performed, and the bacteria were identified through mass spectrometry. RESULTS: Mass spectrometry data indicated that the infection bacteria were Gardnerella vaginalis. The patient's temperature returned to normal after oral ampicillin in combination with clindamycin. CONCLUSIONS: Gardnerella vaginalis bacteremia is very rare in clinical practice, and the combination of ampicillin and clindamycin has a good therapeutic effect. This study may provide a reference for the diagnosis and treatment of Gardnerella vaginalis bacteremia.
Subject(s)
Bacteremia , Uterine Myomectomy , Vaginosis, Bacterial , Female , Pregnancy , Humans , Adult , Gardnerella vaginalis , Pregnant Women , Clindamycin/therapeutic use , Cesarean Section/adverse effects , Ampicillin/therapeutic use , Bacteremia/diagnosis , Bacteremia/drug therapy , Bacteremia/microbiology , Vaginosis, Bacterial/drug therapy , VaginaABSTRACT
In this study, we employed a combination approach for the preparative separation of constituents from Ginkgo biloba L. leaves. It involved multi-stage solvent extractions utilizing two-phase multi-solvent systems and countercurrent chromatography (CCC) separations using three different solvent systems. The n-heptane/ethyl acetate/water (1:1:2, v/v) and n-heptane/ethyl acetate/methanol/water (HepEMWat, 7:3:7:3, v/v) solvent systems were screened out as extraction systems. The polarities of the upper and lower phases in the multi-solvent systems were adjustable, enabling the effectively segmented separation of complex constituents in G. biloba L. The segmented products were subsequently directly utilized as samples and separated using CCC with the solvent systems acetate/n-butanol/water (4:1:5, v/v), HepEMWat (5:5:5:5, v/v), and HepEMWat (9:1:9:1, v/v), respectively. As a result, a total of 11 compounds were successfully isolated and identified from a 2 g methanol extract of G. biloba L through two-stage extraction and three CCC separation processes; among them, nine compounds exhibited high-performance liquid chromatography purity exceeding 85%.
Subject(s)
Countercurrent Distribution , Ginkgo biloba , Plant Extracts , Plant Leaves , Solvents , Ginkgo biloba/chemistry , Solvents/chemistry , Plant Leaves/chemistry , Plant Extracts/chemistry , Plant Extracts/isolation & purification , Chromatography, High Pressure Liquid , Water/chemistry , Methanol/chemistry , Acetates/chemistry , Ginkgo ExtractABSTRACT
PURPOSE: To validate the Graves ophthalmopathy quality of life (GO-QOL) questionnaire in screening DON and to construct an effective model. METHODS: A total of 194 GO patients were recruited and divided into DON and non-DON (mild and moderate-to-severe) groups. Eye examinations were performed, and quality of life was assessed by the GO-QOL questionnaire. The random forest, decision tree model, receiver operator characteristic (ROC) curve, accuracy and Brier score were determined by R software. RESULTS: In GO-QOL, age, best corrected visual acuity (BCVA), exophthalmos, CAS, severity, and Gorman score were found to be factors related to visual function scores. On the appearance scale, gender, duration of GO, BCVA, exophthalmos, CAS and severity of GO were relevant. Both the visual function scores and appearance scores were significantly lower in DON groups than in non-DON groups (33.18 ± 24.54 versus 81.26 ± 17.39, 60.08 ± 24.82 versus 76.14 ± 27.56). The sensitivity, specificity, and AUC of the visual function scores were 91.1%, 81.7% and 0.939, respectively Visual function scores were used to construct a decision tree model. The sensitivity, specificity, and AUC of the model were 92.9%, 88.0% and 0.941, respectively, with an accuracy of 89.7% and a Brier score of 0.024. CONCLUSIONS: Visual function scores were qualified as a screening method for DON, with a cutoff point of 58. A multifactorial screening model based on visual function scores was constructed.
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BACKGROUND: Metabolic syndrome (MetS) is a risk factor for cardiovascular disease (CVD), and CVD is a major challenge for cancer patients. This study aimed to investigate the prevalence and association of MetS and CVD among adult cancer patients. METHODS: This cross-sectional study included cancer patients aged > 18 years from the National Health and Nutrition Examination Survey (NHANES) from 2007 to 2018. The prevalence of MetS and CVD was calculated using weighted analysis. Multivariable logistic regression was used to assess the association between MetS and CVD. RESULTS: The study included 2658 adult cancer patients, of whom 1260 exhibited MetS and 636 had CVD. The weighted prevalence of MetS and CVD in cancer patients was 45.44%, and 19.23%, respectively. Multivariable logistic regression showed a 79% increased risk in higher CVD prevalence in cancer patients with MetS, with the OR (95% CI) of 1.79 (1.31, 2.44). Notably, obesity, elevated blood pressure (BP), high glucose, and low high density lipoprotein cholesterol (HDL-C) in the MetS components were significantly associated with higher CVD prevalence after adjusting for covariates. Moreover, the risk of CVD prevalence in cancer patients increased with more MetS components. Notably, MetS was more strongly linked to CVD in patients aged < 65 and women. CONCLUSIONS: Among adult cancer patients, over two-fifths (45.44%) were estimated to have MetS, while about one-fifth (19.23%) were considered to have CVD. Notably, obesity, elevated BP, high glucose, low HDL-C, and higher number of MetS components were found to be significantly associated with higher CVD prevalence among cancer adults. Cancer patients under 65 and women with MetS may be at increased risk of CVD.
Subject(s)
Cardiovascular Diseases , Metabolic Syndrome , Neoplasms , Nutrition Surveys , Humans , Female , Male , Metabolic Syndrome/epidemiology , Neoplasms/epidemiology , Neoplasms/complications , Cross-Sectional Studies , Middle Aged , Cardiovascular Diseases/epidemiology , Adult , Prevalence , Aged , Risk Factors , United States/epidemiology , Young AdultABSTRACT
Human noroviruses (HuNoVs) are the leading etiological agent causing the worldwide outbreaks of acute epidemic non-bacterial gastroenteritis. Histo-blood group antigens (HBGAs) are commonly acknowledged as cellular receptors or co-receptors for HuNoVs. However, certain genotypes of HuNoVs cannot bind with any HBGAs, suggesting potential additional co-factors and attachment receptors have not been identified yet. In addition, food items, such as oysters and lettuce, play an important role in the transmission of HuNoVs. In the past decade, a couple of attachment factors other than HBGAs have been identified and analyzed from foods and microbiomes. Attachment factors exhibit potential as inhibitors of viral binding to receptors on host cells. Therefore, it is imperative to further characterize the attachment factors for HuNoVs present in foods to effectively control the spread of HuNoVs within the food chain. This review summarizes the potential attachment factors/receptors of HuNoVs in humans, foods, and microbiome.
Subject(s)
Caliciviridae Infections , Gastroenteritis , Norovirus , Virus Attachment , Norovirus/genetics , Norovirus/physiology , Humans , Gastroenteritis/virology , Gastroenteritis/microbiology , Caliciviridae Infections/virology , Receptors, Virus/metabolism , Receptors, Virus/genetics , Animals , Blood Group Antigens/metabolism , Food MicrobiologyABSTRACT
In recent decades, there has been increasing interest in elucidating the role of sulfur-containing compounds in plant metabolism, particularly emphasizing their function as signaling molecules. Among these, thiocyanate (SCN-), a compound imbued with sulfur and nitrogen, has emerged as a significant environmental contaminant frequently detected in irrigation water. This compound is known for its potential to adversely impact plant growth and agricultural yield. Although adopting exogenous SCN- as a nitrogen source in plant cells has been the subject of thorough investigation, the fate of sulfur resulting from the assimilation of exogenous SCN- has not been fully explored. There is burgeoning curiosity in probing the fate of SCN- within plant systems, especially considering the possible generation of the gaseous signaling molecule, hydrogen sulfide (H2S) during the metabolism of SCN-. Notably, the endogenous synthesis of H2S occurs predominantly within chloroplasts, the cytosol, and mitochondria. In contrast, the production of H2S following the assimilation of exogenous SCN- is explicitly confined to chloroplasts and mitochondria. This phenomenon indicates complex interplay and communication among various subcellular organelles, influencing signal transduction and other vital physiological processes. This review, augmented by a small-scale experimental study, endeavors to provide insights into the functional characteristics of H2S signaling in plants subjected to SCN--stress. Furthermore, a comparative analysis of the occurrence and trajectory of endogenous H2S and H2S derived from SCN--assimilation within plant organisms was performed, providing a focused lens for a comprehensive examination of the multifaceted roles of H2S in rice plants. By delving into these dimensions, our objective is to enhance the understanding of the regulatory mechanisms employed by the gasotransmitter H2S in plant adaptations and responses to SCN--stress, yielding invaluable insights into strategies for plant resilience and adaptive capabilities.
Subject(s)
Hydrogen Sulfide , Plants , Signal Transduction , Thiocyanates , Hydrogen Sulfide/metabolism , Thiocyanates/metabolism , Plants/metabolism , Gasotransmitters/metabolism , Chloroplasts/metabolism , Inactivation, MetabolicABSTRACT
PURPOSE: Although urgent orbital decompression surgery for sight-threatening Graves' orbitopathy unresponsive to available medical treatments continues to evolve, post-operative new-onset or worsened pre-operative strabismus or diplopia remains a significant complication. At present, the optimal surgical technique remains debatable. Here, we sought to compare long-term outcomes after balanced medial-lateral wall versus selective 3-wall decompression as an urgent treatment for unresponsive sight-threatening GO. METHODS: This retrospective study examined the post-operative outcome of 102 eyes (57 patients) that underwent urgent orbital decompression for sight-threatening GO. Treatment effectiveness was measured by visual acuity, proptosis, perimetry, and strabismus/diplopia, while fundus findings were detected by fundus color photography and optical coherence tomography and followed up for more than 12 months. RESULTS: Fifty-seven patients (102 orbits) with an average age of 52.7 ± 10.2 years were evaluated. Balanced medial-lateral wall (BMLW-OD) or selective 3-wall decompression(S3W-OD) were performed in 54 and 48 eyes, respectively. Twelve months after orbital decompression, all parameters significantly improved in both groups, including best-corrected visual acuity (BCVA), mean defect of visual field (VF-MD), pattern standard deviation of visual field (VF-PSD), and proptosis (all P < 0.01). However, new-onset esotropia occurred in 25.8% and 3.8% of patients who underwent BMLW-OD surgery or S3W-OD, respectively. Moreover, 6.5% and 38.5% of patients improved after decompression in the medial-lateral wall decompression group and the selective 3-wall decompression group, respectively. CONCLUSIONS: We demonstrated that S3W-OD provides a lower rate of new-onset strabismus/diplopia as compared with BMLW-OD surgery, while still allowing for satisfactory visual outcomes. TRIAL REGISTRATION NUMBER: : NCT05627401. Date of registration: November 25, 2022.
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Muscles play an indispensable role in human life. Surface electromyography (sEMG), as a non-invasive method, is crucial for monitoring muscle status. It is characterized by its real-time, portable nature and is extensively utilized in sports and rehabilitation sciences. This study proposed a wireless acquisition system based on multi-channel sEMG for objective monitoring of grip force. The system consists of an sEMG acquisition module containing four-channel discrete terminals and a host computer receiver module, using Bluetooth wireless transmission. The system is portable, wearable, low-cost, and easy to operate. Leveraging the system, an experiment for grip force prediction was designed, employing the bald eagle search (BES) algorithm to enhance the Random Forest (RF) algorithm. This approach established a grip force prediction model based on dual-channel sEMG signals. As tested, the performance of acquisition terminal proceeded as follows: the gain was up to 1125 times, and the common mode rejection ratio (CMRR) remained high in the sEMG signal band range (96.94 dB (100 Hz), 84.12 dB (500 Hz)), while the performance of the grip force prediction algorithm had an R2 of 0.9215, an MAE of 1.0637, and an MSE of 1.7479. The proposed system demonstrates excellent performance in real-time signal acquisition and grip force prediction, proving to be an effective muscle status monitoring tool for rehabilitation, training, disease condition surveillance and scientific fitness applications.
Subject(s)
Algorithms , Electromyography , Hand Strength , Electromyography/methods , Humans , Hand Strength/physiology , Male , Signal Processing, Computer-Assisted , Adult , Wearable Electronic Devices , Muscle, Skeletal/physiology , Monitoring, Physiologic/methods , Monitoring, Physiologic/instrumentation , Wireless Technology/instrumentationABSTRACT
BACKGROUND: The incidence of clinically avoidable enteral nutrition interruptions is high. ICU nurses, as the implementers and monitors of enteral nutrition, have a close relationship between their cognitive level of enteral nutrition interruption and the incidence of enteral nutrition interruption. The level of ICU nurses' cognition of enteral nutrition interruption and the key factors influencing the level of ICU nurses' cognition of enteral nutrition interruption are not known. OBJECTIVES: This study aims to explore the cognitive level of ICU nurses on enteral nutrition interruption and delve into the key factors that affect their cognitive level from the perspective of management. DESIGN: A sequential explanatory mixed methods research design was used. METHODS: With the convenience sampling method, an online survey questionnaire was distributed to ICU nurses in Chongqing, and 336 valid questionnaires were collected. After the survey, ICU managers were invited to participate in qualitative interviews, in which 10 participants from five hospitals completed face-to-face individual semi-structured interviews and were analyzed with thematic analysis. RESULTS: The survey found that ICU nurses had a good level of cognition towards enteral nutrition interruption but poor knowledge about the definition, causes, and consequences of enteral nutrition interruption, as well as negative attitudes toward active learning, assessment, and communication. And the longer work time in the ICU, joining the nutrition team, receiving systematic training, and acquiring relevant knowledge from academic journals more frequently were favorable to improving ICU nurses' knowledge level of enteral nutrition interruption. Personal interviews further identified the key factors affecting their cognitive level, including (1) lack of knowledge, (2) lack of proactive thinking, (3) lack of enteral nutrition management programs, and (4) lack of quality management tools for enteral nutrition interruption. CONCLUSION: Although ICU nurses demonstrate a relatively high level of cognition, there is still room for improvement. ICU administrators must take specific measures to improve the knowledge of ICU nurses, especially in non-tertiary hospitals, in order to prevent nurse-induced enteral nutrition interruption in all ICUs and improve medical quality. TRIAL REGISTRATION: Not applicable.
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To understand the genome-wide information of the GRF family genes in broomcorn millet and their expression profile in the vegetative meristems, bioinformatic methods and transcriptome sequencing were used to analyze the characteristics, physical and chemical properties, phylogenetic relationship, chromosome distribution, gene structure, cis-acting elements and expression profile in stem meristem for the GRF family members. The results showed that the GRF gene family of millet contains 21 members, and the PmGRF gene is unevenly distributed on 12 chromosomes. The lengths of PmGRF proteins vary from 224 to 618 amino acids, and the isoelectric points are between 4.93-9.69. Each member of the family has 1-4 introns and 2-5 exons. The protein PmGRF13 is localized in both the nucleus and chloroplast, and the rest PmGRF proteins are located in the nucleus. Phylogenetic analysis showed that the 21 GRF genes were divided into 4 subfamilies (A,B,C and D) in broomcorn millet. The analysis of cis-acting elements showed that there were many cis-acting elements involved in light response, hormone response, drought induction, low temperature response and other environmental stress responses in the 2000 bp sequence upstream of the GRF genes. Transcriptome sequencing and qRT-PCR analyses showed that the expression levels of PmGRF3 and PmGRF12 in the dwarf variety Zhang778 were significantly higher than those of the tall variety Longmi12 in the internode and node meristems at the jointing stage, while the expression patterns of PmGRF4, PmGRF16 and PmGRF21 were reverse. In addition, the expression levels of PmGRF2 and PmGRF5 in the internode of Zhang778 were significantly higher than Longmi12. The other GRF genes were not or insignificantly expressed. These results indicated that seven genes, PmGRF2, PmGRF3, PmGRF4, PmGRF5, PmGRF12, PmGRF16 and PmGRF21, were related to the formation of plant height in broomcorn millet.
Subject(s)
Panicum , Phylogeny , Panicum/chemistry , Panicum/genetics , Transcription Factors/genetics , Meristem , Genome, PlantABSTRACT
Background: To assess the link between serum potassium ( K + ) and all-cause mortality in hospitalized heart failure (HF) patients. Methods: Hospitalized HF patients (n = 3114) were analyzed at the Fuwai Hospital Heart Failure Center. Before discharge, HF patients were divided into four groups according to the K + level quartiles: K + ≤ 3.96 mmol/L (Q1), 3.96 < K + ≤ 4.22 mmol/L (Q2), 4.22 < K + ≤ 4.52 mmol/L (Q3), and K + > 4.52 mmol/L (Q4). At 90 days, 2 years, and maximal follow-up, all-cause mortality was the primary outcome. Results: Patients with HF in the Q4 group had worse cardiac function, higher N-terminal pro-B-type natriuretic peptide levels, lower left ventricular ejection fractions and lower estimated glomerular filtration rates than patients in the Q2 group. In the multivariate-adjusted Cox analysis, the mortality assessed during the 90-day, 2-year, and maximal follow-up examinations increased in the Q4 group of HF patients but not in the Q1 and Q3 groups. The Q4 group had a 28% (hazard ratio [HR]: 1.28, 95% confidence interval [CI]: 1.09-1.49, p = 0.002) higher risk of all-cause mortality at maximum follow-up. Hypokalemia and hyperkalemia were linked to increased HF mortality risk at the 90-day, 2-year, and maximal follow-up periods. Conclusions: Serum K + levels had a J-shaped association with all-cause mortality in HF patients. Both hypokalemia and a K + level of > 4.52 mmol/L were associated with increased all-cause mortality in the short term and long term, suggesting a narrow target K + range in HF patients. Clinical Trial Registration: Unique Identifier: NCT02664818; URL: clinicaltrials.gov.
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Subsoil (below 20 cm), storing over 50 % of soil organics carbon (SOC) within the 1 m depth, plays a critical role in regulating climate and ecosystem function. However, little was known on the changes in SOC decomposition induced by exogenous C input (i.e., priming effect) across the whole soil profile under nitrogen (N) enrichment and climate warming. We designed an incubation system of soil columns with minor physical disturbance, which allows the manual additions of exogenous C and N and incubation under ambient or elevated temperature. A negative priming effect by glucose was observed in all layers of ambient soil, while the negative priming effect was enhanced by soil depth but inhibited by warming. Nitrogen addition shifted the priming effect from negative to positive under ambient temperature, and decreased the magnitude of negative priming effect under elevated temperature. Nitrogen uplift effect on priming effect was more pronounced in subsoil compared to topsoil, while this effect diminished with rising temperature. Soil microbial activity (e.g., the CO2 production within 3 days) and acid phosphatase activity had important roles in regulating the variations in priming effect across the soil profile. Our results indicated that increase in labile substrate (e.g., exogenous C input) input would not lead to native SOC destabilization in subsoil, N addition shifted the priming effect from negative to positive, increasing the SOC decomposition under ambient temperature, while labile C input together with N addition benefited SOC sequestration by inducing negative priming effects in forest soil under warming climate.
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The effect of boron (B) deficiency on mediating the contribution of H+-ATPase in the uptake and assimilation of exogenous cyanide (CN-) is investigated. Under CN- treatments, rice seedlings with B-deficient (-B) conditions exhibited significantly higher CN- uptake and assimilation rates than B-supplemented (+B) seedlings, whereas NH4+ uptake and assimilation rates were slightly higher in -B rice seedlings than in +B. In this connection, the expression pattern of genes encoding ß-CAS, ST, and H+-ATPase was assessed to unravel their role in the current scenario. The abundances of three ß-CAS isogenes (OsCYS-D1, OsCYS-D2, and OsCYS-C1) in rice tissues are upregulated from both "CN--B" and "CN-+B" treatments, however, only OsCYS-C1 in roots from the "CN--B" treatments was significantly upregulated than "CN-+B" treatments. Expression patterns of ST-related genes (OsStr9, OsStr22, and OsStr23) are tissue specific, in which significantly higher upregulation of ST-related genes was observed in shoots from "CN--B" treatments than "CN-+B" treatments. Expression pattern of 7 selected H+-ATPase isogenes, OsA1, OSA2, OsA3, OsA4, OsA7, OsA8, and OsA9 are quite tissue specific between "CN-+B" and "CN--B" treatments. Among these, OsA4 and OsA7 genes were highly activated in the uptake and assimilation of exogenous CN- in -B nutrient solution. These results indicated that B deficiency disturbs the pattern of N cycles in CN--treated rice seedlings, where activation of ST during CN- assimilation decreases the flux of the innate pool of NH4+ produced from CN- assimilation by the ß-CAS pathway in plants. Collectively, the B deficiency increased the uptake and assimilation of exogenous CN- through activating H+-ATPase.
Subject(s)
Cyanides , Oryza , Oryza/metabolism , Boron/metabolism , Proton-Translocating ATPases/genetics , Proton-Translocating ATPases/metabolism , Proton-Translocating ATPases/pharmacology , Seedlings/metabolism , Cell Membrane , Plant Roots/metabolismABSTRACT
Plant- and microbial-derived organic carbon, two components of the soil organic carbon (SOC) pool in terrestrial ecosystems, are regulated by increased atmospheric nitrogen (N) deposition. However, the spatial patterns and driving factors of the responses of plant- and microbial-derived SOC to N deposition in forests are not clear, which hinders our understanding of SOC sequestration. In this study, we explored the spatial patterns of plant- and microbial-derived SOC, and their responses to N addition and elucidated their underlying mechanisms in forest soils receiving N addition at four sites with various soil and climate conditions. Plant- and microbial-derived SOC were quantified using lignin phenols and amino sugars, respectively. N addition increased the total microbial residues by 20.5% on average ranging from 9.4% to 34.0% in temperate forests but not in tropical forests, and the increase was mainly derived from fungal residues. Lignin phenols increased more in temperate forests (average of 63.8%) than in tropical forests (average of 15.7%) following N addition. The ratio of total amino sugars to lignin phenols was higher in temperate forests than in tropical forests and decreased with N addition in temperate forests. N addition mainly regulated soil microbial residues by affecting pH, SOC, exchangeable Ca2+, gram-negative bacteria biomass, and the C:N ratio, while it mainly had indirect effects on lignin phenols by altering SOC, soil C:N ratio, and gram-negative bacteria biomass. Overall, our findings suggested that N deposition caused a greater increase in plant-derived SOC than in microbial-derived SOC and that plant-derived SOC would have a more important role in sequestering SOC under increasing N deposition in forest ecosystems, particularly in temperate forests.
Subject(s)
Ecosystem , Tracheophyta , Carbon , Soil/chemistry , Nitrogen/analysis , Lignin , Forests , Soil Microbiology , Amino Sugars , PhenolsABSTRACT
Covalent organic frameworks have attracted considerable attention in recent years as a distinct class of crystalline porous organic materials. Their functional properties are inherently linked to their structural characteristics. Although hundreds of COFs have been reported so far, the types of their topologic structure are still limited. In this article, we report the identification of mcm topology for three porphyrin-based two-dimensional COFs, which are constructed from [4 + 4] imine condensation reactions. The mcm net is generated by pentagonal tiling, which has not been identified for COFs before. The structure of the COFs is elucidated by a variety of experimental characterization and structural simulations, by which their reticular frameworks exclusively composed of pentagonal pores have been confirmed. Moreover, the COFs exhibit high performance in photocatalytic hydrogen evolution from water, with the best one up to 10.0 mmol g-1 h-1 after depositing 0.76 wt% Pt as a co-catalyst. This study identifies mcm topology for COFs for the first time and highlights the potential of these COFs as promising photocatalysts for sustainable hydrogen production from water.