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When interspecific gene flow is common, species relationships are more accurately represented by a phylogenetic network than by a bifurcating tree. This study aimed to uncover the role of introgression in the evolution of Osmanthus, the only genus of the subtribe Oleinae (Oleaceae) with its distribution center in East Asia. We built species trees, detected introgression, and constructed networks using multiple kinds of sequencing data (whole genome resequencing, transcriptome sequencing, and Sanger sequencing of nrDNA) combined with concatenation and coalescence approaches. Then, based on well-understood species relationships, historical biogeographic analyses and diversification rate estimates were employed to reveal the history of Osmanthus. Osmanthus originated in mid-Miocene Europe and dispersed to the eastern Tibetan Plateau in the late Miocene. Thereafter, it continued to spread eastwards. Phylogenetic conflict is common within the 'Core Osmanthus' clade and is seen at both early and late stages of diversification, leading to hypotheses of net-like species relationships. Incomplete lineage sorting proved ineffective in explaining phylogenetic conflicts and thus supported introgression as the main cause of conflicts. This study elucidates the diversification history of a relict genus in the subtropical regions of eastern Asia and reveals that introgression had profound effects on its evolutionary history.
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Genoma , Filogenia , Análisis de Secuencia de ADN , Europa (Continente)RESUMEN
Two novel Gram-stain-negative, aerobic, non-motile and rod-shaped bacteria, designated as WL0004T and XHP0148T, were isolated from seawater samples collected from the coastal areas of Nantong and Lianyungang, PR China, respectively. Both strains were found to grow at 10-42â°C (optimum, 37â°C) and with 2.0-5.0â% (w/v) NaCl (optimum, 3.0â%). Strain WL0004T grew at pH 6.0-9.0 (optimum, pH 7.0-8.0), while XHP0148T grew at pH 6.0-10.0 (optimum, pH 7.0-8.0). The major cellular fatty acids (>10â%) of both strains included summed feature 8 (C18â:â1 ω6c and/or C18â:â1 ω7c). In addition, strain WL0004T contained 11-methyl C18â:â1 ω7c and strain XHP0148T contained C12â:â0 3-OH. The respiratory quinone of both strains was ubiquinone-10. The G+C content of genomic DNA of strains WL0004T and XHP0148T were 62.5 and 63.0âmol%, respectively. Strains WL0004T and XHP0148T showed the highest 16S rRNA gene sequence similarity to Ruegeria pomeroyi DSS-3T (99.4 and 99.0â%, respectively), and the 16S rRNA gene-based phylogenetic analysis indicated that the two strains were closely related to members of the genus Ruegeria. The average nucleotide identity and digital DNA-DNA hybridization values among the two strains and type strains of the genus Ruegeria were all below 95 and 70â%, respectively, and the phylogenetic tree reconstructed from the bac120 gene set indicated that the two strains are distinct from each other and the members of the genus Ruegeria. Based on this phenotypic and genotypic characterization, strains WL0004T (=MCCC 1K07523T=JCM 35565T=GDMCC 1.3083T) and XHP0148T (=MCCC 1K07543T=JCM 35569T=GDMCC 1.3089T) should be recognized as representing two novel species of the genus Ruegeria and the names Ruegeria marisflavi sp. nov. and Ruegeria aquimaris sp. nov. are proposed, respectively.
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Ácidos Grasos , Agua de Mar , Composición de Base , Ácidos Grasos/química , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , ADN Bacteriano/genética , Técnicas de Tipificación BacterianaRESUMEN
The microalga Chlorella pyrenoidosa is cultivated extensively for its constituents, which are of significant economic worth. Large-scale growth of C. pyrenoidosa in outdoor environments is subject to various stressors such as elevated temperature. The purpose of this study was to assess the protective effects of exogenous 24-epibrassinolide (EBL) on C. pyrenoidosa under high-temperature conditions. Compared to a temperature of 30°C, increasing the temperature to 43°C reduced the enzymatic capacity for carbon assimilation and resulted in the buildup of reactive oxygen species (ROS), thus reducing photosynthesis and proliferation. It was observed that exogenous EBL protected C. pyrenoidosa cells against high temperatures, with an optimal EBL concentration of 100 nM, resulting in enhanced capacity for photosynthetic carbon assimilation with a notable reduction in the imbalance between the absorption of light and energy used under high-temperature conditions. The addition of 100 nM EBL resulted in a 25.4% increase in cell density when exposed to elevated temperatures for 7 days. In addition, exogenous EBL reduced ROS production and increased the activities of critical antioxidant enzymes. This, in turn, mitigated heat-induced oxidative damage, resulting in advantageous outcomes in terms of cellular development and maintenance.
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Brasinoesteroides , Chlorella , Esteroides Heterocíclicos , Temperatura , Especies Reactivas de Oxígeno , Fotosíntesis , Estrés Oxidativo , Proliferación Celular , CarbonoRESUMEN
Oxybenzone (OBZ; benzophenone-3, CAS# 131-57-7), as a new pollutant and ultraviolet absorbent, shows a significant threat to the survival of phytoplankton. This study aims to explore the acute toxic effects of OBZ on the growth of the microalga Selenastrum capricornutum, as well as the mechanisms for its damage to the primary metabolic pathways of photosynthesis and respiration. The results demonstrated that the concentrations for 50â¯% of maximal effect (EC50) of OBZ for S. capricornutum were 9.07â¯mgâ¯L-1 and 8.54â¯mgâ¯L-1 at 72â¯h and 96â¯h, respectively. A dosage of 4.56â¯mgâ¯L-1 OBZ significantly lowered the photosynthetic oxygen evolution rate of S. capricornutum in both light and dark conditions for a duration of 2â¯h, while it had no effect on the respiratory oxygen consumption rate under darkness. OBZ caused a significant decline in the efficiency of photosynthetic electron transport due to its damage to photosystem II (PSII), thereby decreasing the photosynthetic oxygen evolution rate. Over-accumulated H2O2 was produced under light due to the damage caused by OBZ to the donor and acceptor sides of PSII, resulting in increased peroxidation of cytomembranes and inhibition of algal respiration. OBZ's damage to photosynthesis and respiration will hinder the conversion and reuse of energy in algal cells, which is an important reason that OBZ has toxic effects on S. capricornutum. The present study indicated that OBZ has an acute toxic effect on the microalga S. capricornutum. In the two most important primary metabolic pathways in algae, photosynthesis is more sensitive to the toxicity of OBZ than respiration, especially in the dark.
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Benzofenonas , Microalgas , Fotosíntesis , Protectores Solares , Fotosíntesis/efectos de los fármacos , Benzofenonas/toxicidad , Microalgas/efectos de los fármacos , Protectores Solares/toxicidad , Contaminantes Químicos del Agua/toxicidad , Peróxido de Hidrógeno/metabolismo , Complejo de Proteína del Fotosistema II/metabolismo , Complejo de Proteína del Fotosistema II/efectos de los fármacos , Rayos Ultravioleta , Transporte de Electrón/efectos de los fármacosRESUMEN
The production of ammonia (NH3) from nitrogen sources involves competitive adsorption of different intermediates and multiple electron and proton transfers, presenting grand challenges in catalyst design. In nature nitrogenases reduce dinitrogen to NH3 using two component proteins, in which electrons and protons are delivered from Fe protein to the active site in MoFe protein for transfer to the bound N2. We draw inspiration from this structural enzymology, and design a two-component metal-sulfur-carbon (M-S-C) catalyst composed of sulfur-doped carbon-supported ruthenium (Ru) single atoms (SAs) and nanoparticles (NPs) for the electrochemical reduction of nitrate (NO3-) to NH3. The catalyst demonstrates a remarkable NH3 yield rate of ~37 mg L-1 h-1 and a Faradaic efficiency of ~97% for over 200 hours, outperforming those consisting solely of SAs or NPs, and even surpassing most reported electrocatalysts. Our experimental and theoretical investigations reveal the critical role of Ru SAs with the coordination of S in promoting the formation of the HONO intermediate and the subsequent reduction reaction over the NP-surface nearby. This study proves a better understanding of how M-S-Cs act as a synthetic nitrogenase mimic during ammonia synthesis, and contributes to the future mechanism-based catalyst design.
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Hypoxia is a major emerging threat to coastal ecosystems, which is closely related to the decline in seagrass meadows, but its damage mechanism is still unclear. This study found that hypoxia at night significantly reduced the photosynthetic capacity of Enhalus acoroides after reillumination. Photosystem II (PSII) was damaged by high-light stress during daytime low-tide exposure, but high-light-damaged PSII of E. acoroides could recover part of its activity indark normoxic seawater to maintain the normal operation of photosynthesis after reillumination during the next day. However, hypoxia inhibited the recovery of damaged PSII under darkness. By transcriptomic analysis and inhibitor verification experiments, dark hypoxia was shown to inhibit respiration, thereby reducing ATP production and preventing ATP from being transported into chloroplasts, which, in turn, led to an insufficient supply of energy required for PSII to recover. This study demonstrated that hypoxia has several negative impacts on the photosynthetic apparatus of E. acoroides at night reducing photosynthetic capacity after reillumination, which may be an important factor leading to the decline of the seagrass meadows.
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Ecosistema , Fotosíntesis , Complejo de Proteína del Fotosistema II/metabolismo , Hipoxia , Adenosina TrifosfatoRESUMEN
Staphylococcus aureus is a common foodborne pathogen and spoilage bacterium in meat products. To develop a natural preservative for meat products, this study revealed the antibacterial activity and mechanism of Rosa roxburghii Tratt pomace crude extract (RRPCE) against S. aureus, and applied RRPCE to the preservation of cooked beef. The diameter of inhibition zone, minimum inhibitory concentration (MIC), and minimum bactericide concentration of RRPCE against S. aureus were 15.85 ± 0.35 to 16.21 ± 0.29 mm, 1.5 mg/mL, and 3 mg/mL, respectively. The growth curve of S. aureus was completely stalled by treatment with RRPCE at 2 MIC. RRPCE results in the decrease of intracellular adenosine 5'-triphosphate (ATP) content, depolarization of cell membrane, leakage of cell fluid including nucleic acid and protein, and destruction of cell membrane integrity and cell morphology. During storage, RRPCE significantly reduced S. aureus viable counts, pH, and total volatile basic nitrogen of cooked beef compared with untreated samples (p < 0.05). In addition, RRPCE could significantly increase the redness (a*) value, decrease lightness (L*) and yellowness (b*) values, and slow down the color change of cooked beef (p < 0.05). These findings suggest that RRPCE can effectively inhibit S. aureus, and has the potential as a natural preservative for the preservation of cooked beef.
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Productos de la Carne , Carne Roja , Rosa , Animales , Bovinos , Staphylococcus aureus , Rosa/química , Carne Roja/microbiología , Antibacterianos/farmacologíaRESUMEN
Flying ad hoc networks (FANETs), composed of small unmanned aerial vehicles (UAVs), possess characteristics of flexibility, cost-effectiveness, and rapid deployment, rendering them highly attractive for a wide range of civilian and military applications. FANETs are special mobile ad hoc networks (MANETs), FANETs have the characteristics of faster network topology changes and limited energy. Existing reactive routing protocols are unsuitable for the highly dynamic and limited energy of FANETs. For the lithium battery-powered UAV, flight endurance lasts from half an hour to two hours. The fast-moving UAV not only affects the packet delivery rate, average throughput, and end-to-end delay but also shortens the flight endurance. Therefore, research is urgently needed into a high-performance routing protocol with high energy efficiency. In this paper, we propose a novel routing protocol called AO-AOMDV, which utilizes arithmetic optimization (AO) to enhance the ad hoc on-demand multi-path distance vector (AOMDV) routing protocol. The AO-AOMDV utilizes a fitness function to calculate the fitness value of multiple paths and employs arithmetic optimization for selecting the optimal route for routing selection. Our experiments were conducted using NS3 with three evaluation metrics: the packet delivery ratio, network lifetime, and average end-to-end delay. We compare this algorithm to routing protocols including AOMDV and AODV. The results indicate that the proposed AO-AOMDV attained a higher packet delivery ratio, network lifetime, and lower average end-to-end delay.
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High temperature detection is a constant challenge for condition monitoring under harsh environments in optical fiber sensors research. In this study, the temperature response characteristics of guided acoustic wave Brillouin scattering (GAWBS) spectra in silica single-mode fiber (SMF) up to 800 °C are experimentally investigated, demonstrating the feasibility of the method for high-temperature monitoring. With increasing temperature, the resonance frequency of GAWBS spectra increases in a nearly linear manner, with linearly fitted temperature-dependent frequency shift coefficients of 8.19 kHz/°C for TR2,7 mode and 16.74 kHz/°C for R0,4 mode. More importantly, the linewidth of the GAWBS spectra is observed to narrow down with increasing temperature with a linearly fitted rate of -6.91 × 10-4/°C for TR2,7 modes and -8.56 × 10-4/°C for R0,4 modes. The signal-to-noise ratio of the GAWBS spectra induced by both modes increase by more than 3 dB when the temperature rises from 22 °C to 800 °C, which indicates that the proposed sensing scheme has better performance in high-temperature environments, and are particularly suitable for sensing applications in extreme environments. This study confirms the potential of high-temperature sensing using only GAWBS in silica fibers without any complex micromachining process, which has the advantages of strong mechanical strength, simple structure, easy operation, and low cost.
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Tunnel magnetoresistance (TMR) can measure weak magnetic fields and has significant advantages for use in alternating current/direct current (AC/DC) leakage current sensors for power equipment; however, TMR current sensors are easily perturbed by external magnetic fields, and their measurement accuracy and measurement stability are limited in complex engineering application environments. To enhance the TMR sensor measurement performance, this paper proposes a new multi-stage TMR weak AC/DC sensor structure with high measurement sensitivity and anti-magnetic interference capability. The front-end magnetic measurement characteristics and interference immunity of the multi-stage TMR sensor are found to be closely related to the multi-stage ring size design via finite element simulation. The optimal size of the multipole magnetic ring is determined using an improved non-dominated ranking genetic algorithm (ACGWO-BP-NSGA-II) to derive the optimal sensor structure. Experimental results demonstrate that the newly designed multi-stage TMR current sensor has a measurement range of 60 mA, a fitting nonlinearity error of less than 1%, a measurement bandwidth of 0-80 kHz, a minimum AC measurement value of 85 µA and a minimum DC measurement value of 50 µA, as well as a strong external electromagnetic interference. The TMR sensor can effectively enhance measurement precision and stability in the presence of intense external electromagnetic interference.
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The status of zinc oxide (ZnO) arresters is directly related to the safety of power grids. However, as the service life of ZnO arresters increases, their insulation performance may decrease due to factors such as operating voltage and humidity, which can be identified through the measurement of leakage current. Tunnel magnetoresistance (TMR) sensors with high sensitivity, good temperature stability, and small size are excellent for measuring leakage current. This paper constructs a simulation model of the arrester and investigates the deployment of the TMR current sensor and the size of the magnetic concentrating ring. The arrester's leakage current magnetic field distribution under different operating conditions is simulated. The simulation model can aid in optimizing the detection of leakage current in arresters using TMR current sensors, and the findings serve as a basis for monitoring the condition of arresters and improving the installation of current sensors. The TMR current sensor design offers potential advantages such as high accuracy, miniaturization, and ease of distributed application measurement, making it suitable for large-scale use. Finally, the validity of the simulations and conclusions is verified through experiments.
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BACKGROUND: Tartary buckwheat protein peptides have been shown to be able to inhibit angiotensin-converting enzyme (ACE), but the exact protein type has been less studied for ACE activity inhibition, and only a few types of ACE inhibitory peptides have been reported. In this study, we purified and identified ACE inhibitory peptides from albumin hydrolysate (AH). RESULTS: Albumin, globulin, prolamin and glutelin were extracted from Tartary buckwheat, and their ACE active peptides were obtained by a pepsin-trypsin sequential hydrolysis process. All four hydrolysates exhibited ACE inhibitory activity, and AH displayed the strongest ACE inhibition activity and the highest peptide yield (82.28%). At 0.2 mg mL-1 , the inhibition rate of AH was 79.89%, followed by globulin hydrolysate at 71.84%, while prolamin hydrolysate and glutelin hydrolysate showed lower inhibition rates. The peptides with the highest inhibition rate were then isolated from AH using gel filtration chromatography and reversed-phase high-performance liquid chromatography, and identified using nanoscale high-performance liquid chromatography-tandem mass spectrometry. After isolation and purification, 42 ACE inhibitory peptides were identified in the fraction with the highest inhibition rate, 14 of which were completely novel discoveries in this study. These 14 peptides showed potent ACE inhibitory effects through computer analysis. CONCLUSION: Tartary buckwheat albumin can be used as a good source of ACE inhibitory peptides and can be further developed and utilized as edible supplements or drugs. © 2023 Society of Chemical Industry.
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Fagopyrum , Globulinas , Inhibidores de la Enzima Convertidora de Angiotensina/química , Fagopyrum/metabolismo , Hidrolisados de Proteína/química , Péptidos/química , Albúminas , Peptidil-Dipeptidasa A/química , Hidrólisis , Glútenes , AngiotensinasRESUMEN
Frequency upconversion technology with good performance including high sensitivity, fast response, and room-temperature operation is a promising method for terahertz-wave detection. The sum-frequency conversion and difference-frequency conversion jointly affect the detection ability for upconversion detection using organic crystals as nonlinear media. The concurrence of both processes has been ignored in past studies, which results in discrepancies between theoretical simulations and experimental results. In this paper, four-wave interaction equations involving two nonlinear conversion processes are proposed, and the effect of the sum-frequency process is analyzed in upconversion terahertz-wave detection via a 4-dimethylamino-N-methyl-4-stilbazolium tosylate (DAST) crystal. The ratio of the sum-frequency signal to the difference-frequency signal varies for different terahertz frequencies and crystal thicknesses. Experiments suggest that theoretical simulations are good at predicting physical processes. Under certain conditions, the detection efficiency can be improved by simultaneously utilizing the two signals. The total signal photon number is not sensitive to the crystal thickness. Furthermore, the theoretical exploration of terahertz single-photon detection provides a noteworthy reference for future experiments.
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We demonstrate that small unidirectional applied-stresses during temperature-induced gelation dramatically change the gel temperature and the resulting mechanical properties and structure of aqueous methylcellulose (MC), a material that forms a brittle gel with a fibrillar microstructure at elevated temperatures. Applied stress makes gelation more difficult, evidenced by an increased gelation temperature, and weakens mechanical properties of the hot gel, evidenced by a decreased elastic modulus and decreased apparent failure stress. In extreme cases, formation of a fully percolated polymer network is inhibited and a soft granular yield-stress fluid is formed. We quantify the effects of the applied stress using a filament-based mechanical model to relate the measured properties to the structural features of the fibril network. The dramatic changes in the gel temperature and hot gel properties give more design freedom to processing-dependent rheology, but could be detrimental to coating applications where gravitational stress during gelation is unavoidable.
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4-hydroxyisoleucine (4-HIL) has a potential value in treating diabetes. The α-ketoglutarate (α-KG)-dependent isoleucine dioxygenase (IDO) can catalyze the hydroxylation of L-isoleucine (Ile) to form 4-HIL by consuming O2. In our previous study, the ido gene was overexpressed in an Ile-producing Corynebacterium glutamicum strain to synthesize 4-HIL from glucose. Here, a triple-functional dynamic control system was designed to regulate the activity of IDO, the supply of α-KG, O2, and Ile and the synthesis of by-product L-lysine (Lys) for promoting 4-HIL synthesis. Firstly, the codon-optimized ido was positively regulated by seven Ile biosensors Lrp-PbrnFEN with different intensities, and the resulting seven D-NI strains produced 38.7-111.1 mM 4-HIL. Then on the basis of D-NI, odhI and vgb were simultaneously regulated by three PbrnFEN with different intensities to synergistically control α-KG and O2 supply. The 4-HIL titer of twelve D-NINONV strains was more than 90 mM, with D-0I7O7V generating the highest titer of 141.1 ± 15.5 mM. Thirdly, ilvA was negatively regulated by an Ile attenuator PilvBNC on the basis of D-NI strains and some D-NINONV strains to balance the synthesis and conversion of Ile. The resulting D-NIPA strains produced 73.6-123.2 mM 4-HIL, while D-7I7O1VPA accumulated 127.1 ± 20.2 mM 4-HIL. Finally, dapA was negatively regulated by a Lys-OFF riboswitch and Lys content decreased by approximately 70% in most D-RS-NIPA strains. A strain D-RS-5IPA with the highest 4-HIL titer (177.3 ± 8.9 mM) and the lowest Lys concentration (6.1 ± 0.6 mM) was successfully obtained. Therefore, dynamic regulation of main and branch pathway by three functional biosensors can effectively promote 4-HIL biosynthesis in C. glutamicum. KEY POINTS: ⢠Three biosensors were coordinated for dynamic 4-HIL biosynthesis in C. glutamicum ⢠Bidirectional regulation of Ile synthesis and conversion promoted 4-HIL synthesis ⢠Negative regulation of Lys synthesis further increased 4-HIL production.
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Técnicas Biosensibles , Corynebacterium glutamicum , Corynebacterium glutamicum/genética , Corynebacterium glutamicum/metabolismo , Isoleucina/análogos & derivados , Ácidos Cetoglutáricos/metabolismoRESUMEN
BACKGROUND: Pediatric meningioma with YAP1 fusion is a rare subset of meningiomas. Currently, there are lack of integrated clinical, radiological, and pathological features on this subset. Here, we reported a case of pediatric meningioma with a novel MAML2-YAP1 fusion variant and reviewed the relevant literature. CASE PRESENTATION: We presented a case of 12-year-old boy with meningioma adjacent to the superior sagittal sinus and falx. Simpson grade II gross total resection was performed after diagnosis. Pathologically, he was diagnosed as WHO grade I meningothelial meningioma with rhabdoid features. A next-generation sequencing-based gene panel was performed to determine the molecular features for potential treatment, and a novel MAML2-YAP1 fusion break point was identified. CONCLUSION: Pediatric meningioma with the fusion of YAP1 and MAML2 genes is more likely to have pathological features of rhabdiod cells, which needs to be validated in large-scale studies for exploring better treatment under the integrated diagnosis.
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Neoplasias Meníngeas , Meningioma , Masculino , Niño , Humanos , Meningioma/diagnóstico por imagen , Meningioma/genética , Factores de Transcripción/genética , Secuenciación de Nucleótidos de Alto Rendimiento , Neoplasias Meníngeas/diagnóstico por imagen , Neoplasias Meníngeas/genética , Transactivadores/genéticaRESUMEN
High-temperature measurements above 1000 °C are critical in harsh environments such as aerospace, metallurgy, fossil fuel, and power production. Fiber-optic high-temperature sensors are gradually replacing traditional electronic sensors due to their small size, resistance to electromagnetic interference, remote detection, multiplexing, and distributed measurement advantages. This paper reviews the sensing principle, structural design, and temperature measurement performance of fiber-optic high-temperature sensors, as well as recent significant progress in the transition of sensing solutions from glass to crystal fiber. Finally, future prospects and challenges in developing fiber-optic high-temperature sensors are also discussed.
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Biochar application is not only being widely promoted as an ideal strategy to mitigate global climate warming, but it also has the advantage of reducing heavy metal bioavailability and migration in the soil. However, studies on the effects of field aging on biochar to reduce heavy metals from the soil are still limited. The present study aimed to explore the effects and mechanisms of aged biochar added to the soil planted with pepper plants on cadmium (Cd) uptake. To achieve this, un-amended soil (control), soil amended with fresh biochar, and aged biochar (biochar recovered from a long-term field trial after 9 years) were used to investigate the effects of field aging on biochar adsorption efficiency. The results revealed that the amount of Cd in the plant planted in control soil, amended with fresh and aged biochar, accounted for 40 ± 6.10, 17.18 ± 1.19, and 18.68 ± 0.79, respectively. There was a significant difference (P < 0.05) in the amount of Cd that was uptaken by plants among all treatments. However, soil amended with fresh biochar significantly (P < 0.05) decreased the amount of Cd in plants compared with soil amended with aged biochar. This indicates that field aging declines the potential of biochar to lower heavy metal bioavailability and retention in the soil. This study demonstrates that long-term burial lessens the ability of biochar to interact with Cd and suggests that biochar amendment can lower Cd in the soil, depending on the freshness and aging of biochar.
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Metales Pesados , Contaminantes del Suelo , Cadmio/análisis , Carbón Orgánico , Plantas , Suelo , Contaminantes del Suelo/análisisRESUMEN
InGaAs/InP-based negative-feedback avalanche diodes (NFADs) for 1550 nm single-photon detection with easy-to-use and low-afterpulsing features have attracted many researchers on lidar and quantum optics. Here we present a fast active-quenching circuit specifically designed to exploit the performance of a multi-mode fiber coupled NFAD for free-running operation by a further suppression on afterpulsing effects. The quenching and recovery processes of the device were characterized using electroluminescent method and a novel dual-pulse method, respectively. Results show that the proposed circuit was capable of reducing the time required for quenching and recovery process of the NFAD by approximately 20 ns, and contributed to a reduction in the number of avalanche carriers by up to 30%. As a result, the total afterpulse probability (TAP) of the NFAD with active quenching was reduced by up to 70% compared with the condition without active quenching, and by approximately 90% compared with a standard InGaAs SPAD at the photon detection efficiency (PDE) of 20%. The TAP of the proposed detector was lower than 11% when the dead time was longer than 200 ns, 600 ns, and 2 µs at the PDE of 10%, 15%, and 25%, respectively, and the usable dead time was down to 80 ns with a TAP of 20.4% at the PDE of 10%, 1550 nm, 223 K, where the DCR was as low as 918 Hz. The low-afterpulsing, low-dead-time, low-DCR features of this compact detector makes it especially suitable for use in lidar applications.
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OBJECTIVE: To evaluate the efficacy and safety of cyclin-dependent kinase 4 and 6 (CDK4/6) inhibitors combined with endocrine therapy (ET) for hormone receptor-positive (HR+)/human epidermal growth factor receptor 2-negative (HER-2-) advanced breast cancer (ABC) patients. METHODS: We searched clinical trials of CDK4/6 inhibitors combined with ET and calculated the clinical outcomes. RESULTS: HR+/HER-2- ABC patients treated with CDK4/6 inhibitors combined with ET had significantly prolonged progression-free survival (PFS) and improved objective response rate (ORR) and clinical benefit rate (CBR). CONCLUSIONS: CDK4/6 inhibitors combined with ET can bring more clinical benefits to ABC patients, and the safety profile is acceptable.