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1.
Heliyon ; 10(9): e30456, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38720716

ABSTRACT

Potatoes, as a high-nitrogen (N)-demand crop, are strongly influenced by both the quantity and form of N supply. Previous studies have demonstrated that applying nitrate N prior to tuber formation and ammonium N post-tuber formation can substantially enhance potato yields and improve N fertilizer use efficiency. However, the ammonium N introduced into the soil undergoes nitrification, creating challenges in aligning the N supply form with the needs of potatoes. This study explored novel N regulation strategies aimed at augmenting potato yields and improving N fertilizer use efficiency. Two field experiments were conducted from 2020 to 2022. Experiment 1 involved four N gradients, namely no N, 150 kg N ha-1, 300 kg N ha-1, and 450 kg N ha-1. Soil samples were collected regularly to determine the transformation patterns of soil ammonium N during potato growth. Experiment 2 included three N management practices: farmer practice (Con), "nitrate followed by ammonium" with nitrification inhibitor (N-NI), and optimization (the soil ammonium N transformation-based split application of N fertilizer, Opt). The potato yield and N fertilizer use efficiency were compared to assess the performance of the optimized strategy. The results showed that 90 % of the ammonium N transformed 20 days after the basal dressing of N. When N fertilizer was applied as top dressing during the tuber formation and bulking stages, more than 90 % of ammonium N was transformed after 10 days. The optimized strategy resulted in a 20 % increase in potato yield, a 20 % increase in N fertilizer partial factor productivity, and a 12-20 % reduction in residual inorganic N in the 0-60 cm soil layer. This suggests that ammonium N applied as base fertilizer exhibits a relatively slow transformation rate, while applying ammonium N as top dressing during the tuber formation and bulking stages accelerates the transformation rate. The split application of ammonium N based on soil ammonium N transformation patterns can improve the alignment between the N supply form with the specific demands of potatoes.

2.
Small ; : e2309891, 2024 May 09.
Article in English | MEDLINE | ID: mdl-38721972

ABSTRACT

Although the current cancer photothermal therapy (PTT) can produce a powerful therapeutic effect, tumor cells have been proved a protective mechanism through autophagy. In this study, a novel hybrid theranostic nanoparticle (CaCO3@CQ@pDB NPs, CCD NPs) is designed and prepared by integrating a second near-infrared (NIR-II) absorbed conjugated polymer DTP-BBT (pDB), CaCO3, and autophagy inhibitor (chloroquine, CQ) into one nanosystem. The conjugated polymer pDB with asymmetric donor-acceptor structure shows strong NIR-II absorbing capacity, of which the optical properties and photothermal generation mechanism of pDB are systematically analyzed via molecular theoretical calculation. Under NIR-II laser irradiation, pDB-mediated PTT can produce powerful killing ability to tumor cells. At the same time, heat stimulates a large amount of Ca2+ inflow, causing calcium overload induced mitochondrial damage and enhancing the apoptosis of tumor cells. Besides, the released CQ blocks the self-protection mechanism of tumor cells and greatly enhances the attack of PTT and calcium overload therapy. Both in vitro and in vivo experiments confirm that CCD NPs possess excellent NIR-II theranostic capacity, which provides a new nanoplatform for anti-tumor therapy and builds great potential for future clinical research.

3.
Minerva Med ; 2024 May 09.
Article in English | MEDLINE | ID: mdl-38727704

ABSTRACT

Stroke confers a severe global healthcare burden, hence exploring risk factors for stroke occurrence and prognosis is important for stroke prevention and post-stroke management strategies. Endogenous fibrinolysis is a spontaneous physiological protective mechanism that dissolves thrombus to maintain vascular patency. Recently, impaired endogenous fibrinolysis has been considered as a potential novel cardiovascular risk factor, but its link with ischaemic stroke in the past has been underappreciated. In this review, we summarize the latest mechanisms of endogenous fibrinolysis, review the current evidence and data on endogenous fibrinolysis in ischemic stroke. It includes the structure of thrombus in ischemic stroke patients, the effect of fibrin structure on the endogenous fibrinolytic efficiency, and the association between intravenous thrombolytic therapy and endogenous fibrinolysis in ischemic stroke. It also includes the single factors (tissue plasminogen activator, urokinase plasminogen activator, plasminogen activator inhibitor-1, thrombin activatable fibrinolysis inhibitor, complement component 3, complement component 5, alpha-2-antiplasmin, plasmin-alpha-2-antiplasmin complex, and lipoprotein[a]), and the global assessments of endogenous fibrinolysis status (thromboelastography, rotational thromboelastometry, and global thrombosis test), and their potential as predictors to identify occurrence or unfavorable functional outcomes of ischemic stroke. All of these assessments present advantages and limitations, and we suggest that the global thrombosis test may be more appropriate for detecting impaired endogenous fibrinolysis status in ischemic stroke patients.

4.
Article in English | MEDLINE | ID: mdl-38758500

ABSTRACT

Due to the unique physiological barriers within the lungs, there are considerable challenges in developing drug delivery systems enabling prolonged drug exposure to respiratory epithelial cells. Here, we report a PulmoSphere-based dry powder technology that incorporates a drug-phospholipid complex to promote intracellular retention of dehydroandrographolide succinate (DAS) in respiratory epithelial cells following pulmonary delivery. The DAS-phospholipid complex has the ability to self-assemble into nanoparticles. After spray-drying to produce PulmoSphere microparticles loaded with the drug-phospholipid complex, the rehydrated microparticles discharge the phospholipid complex without altering its physicochemical properties. The microparticles containing the DAS-phospholipid complex exhibit remarkable aerodynamic properties with a fine particle fraction of ∼ 60% and a mass median aerodynamic diameter of ∼ 2.3 µm. These properties facilitate deposition in the alveolar region. In vitro cell culture and lung tissue explants experiments reveal that the drug-phospholipid complex prolongs intracellular residence time and lung tissue retention due to the slow intracellular disassociation of drug from the complex. Once deposited in the lungs, the DAS-phospholipid complex loaded microparticles increase and extend drug exposure to the lung tissues and the immune cells compared to the free DAS counterpart. The improved drug exposure to airway epithelial cells, but not immune cells, is related to a prolonged duration of pulmonary anti-inflammation at decreased doses in a mouse model of acute lung injury induced by lipopolysaccharide. Overall, the phospholipid complex loaded microparticles present a promising approach for improved treatment of respiratory diseases, e.g. pneumonia and acute respiratory distress syndrome.

5.
Transl Cancer Res ; 13(4): 1665-1684, 2024 Apr 30.
Article in English | MEDLINE | ID: mdl-38737689

ABSTRACT

Background: Early-onset colorectal cancer (EOCRC) is increasing in incidence and poses a growing threat. Urgent research is needed, especially in survival analysis, to enhance comprehension and treatment strategies. This study aimed to explore the risk factors associated with cancer-specific mortality (CSM) and other-cause mortality (OCM) in patients with EOCRC. Additionally, the study aimed to develop a nomogram predicting CSM using a competitive risk model and validate its accuracy through the use of training, using internal and external cohorts. Methods: Data from EOCRC patients were collected from the Surveillance, Epidemiology, and End Results (SEER) database (2008-2017). EOCRC patients who were treated at a tertiary hospital in northeast China between 2014 and 2020 were also included in the study. The SEER data were divided into the training and validation sets at a 7:3 ratio. A univariate Cox regression model was employed to identify prognostic factors. Subsequently, multivariate Cox regression models were applied to ascertain the presence of independent risk factors. A nomogram was generated to visualize the results, which were evaluated using the concordance index (C-index), area under the curve (AUC), and calibration curves. The clinical utility was assessed via decision curve analysis (DCA). Results: Multivariable Cox regression analysis demonstrated that factors such as race, tumor differentiation, levels of carcinoembryonic antigen (CEA), marital status, histological type, American Joint Committee on Cancer (AJCC) stage, and surgical status were independent risk factors for CSM in EOCRC patients. In addition, age, gender, chemotherapy details, CEA levels, marital status, and AJCC stage were established as independent risk factors for OCM in individuals diagnosed with EOCRC. A nomogram was developed using the identified independent risk factors, demonstrating excellent performance with a C-index of 0.806, 0.801, and 0.810 for the training, internal validation, and external validation cohorts, respectively. The calibration curves and AUC further confirmed the accuracy and discriminative ability of the nomogram. Furthermore, the DCA results indicated that the model had good clinical value. Conclusions: In this study, a competing risk model for CSM was developed in EOCRC patients. The model demonstrates a high level of predictive accuracy, providing valuable insights into the treatment decision-making process.

6.
bioRxiv ; 2024 May 03.
Article in English | MEDLINE | ID: mdl-38746285

ABSTRACT

Lyme disease is a tick-borne, multisystem infection caused by the spirochete, Borreliella burgdorferi . Although antibodies have been implicated in the resolution of Lyme disease, the specific B cell epitopes targeted during human infections remain largely unknown. In this study, we characterized and defined the structural epitope of a patient-derived bactericidal monoclonal IgG ("B11") against Outer surface protein C (OspC), a homodimeric lipoprotein necessary for B. burgdorferi tick-mediated transmission and early-stage colonization of vertebrate hosts. High-resolution epitope mapping was accomplished through hydrogen deuterium exchange-mass spectrometry (HDX-MS) and X-ray crystallography. Structural analysis of B11 Fab-OspC A complexes revealed the B11 Fabs associated in a 1:1 stoichiometry with the lateral faces of OspC A homodimers such that the antibodies are essentially positioned perpendicular to the spirochete's outer surface. B11's primary contacts reside within the membrane proximal regions of α-helices 1 and 6 and adjacent loops 5 and 6 in one OspC A monomer. In addition, B11 spans the OspC A dimer interface, engaging opposing α-helix 1', α-helix 2', and loop 2-3' in the second OspC A monomer. The B11-OspC A structure is reminiscent of the recently solved mouse transmission blocking monoclonal IgG B5 in complex with OspC A , indicating a mode of engagement with OspC that is conserved across species. In conclusion, we provide the first detailed insight into the interaction between a functional human antibody and an immunodominant Lyme disease antigen long considered an important vaccine target.

7.
J Colloid Interface Sci ; 669: 258-264, 2024 May 01.
Article in English | MEDLINE | ID: mdl-38718579

ABSTRACT

For ethylene purification, C2H6-selective metal-organic frameworks (MOFs) show great potential to directly produce polymer-grade C2H4 from C2H6/C2H4 mixtures. Most C2H6-traping MOFs are ultra-microporous structures so as to strengthen multiple supramolecular interactions with C2H6. However, the narrowed pore channels of C2H6-traping MOFs cause large guest diffusion barriers, greatly hampering their practical applications. Herein, we present a feasible strategy by precisely constructing hierarchically porous MOF@COF core-shell structures to address this issue. Additional mesoporous diffusion channels were incorporated between MOF crystals through the construction of the COF shell, thereby enhancing the gas adsorption kinetics. Notably, designing a core-shell MOF@COF structure with an optimal coating amount of mesoporous COF shell will further improve the gas diffusion rate. Breakthrough experiments reveal that the tailored MOF@COF composites can effectively achieve C2H6/C2H4 separation and maintain its separation performance over five continuous measurement cycles. This investigation opens up a new avenue to solve the diffusion/transfer issues and provides more opportunities and potentials for MOF@COF composites in practical separation applications.

8.
J Ovarian Res ; 17(1): 98, 2024 May 09.
Article in English | MEDLINE | ID: mdl-38725001

ABSTRACT

Ovarian Hyperstimulation Syndrome (OHSS) is a systemic condition marked by the enlargement of the ovaries and heightened vascular permeability. And hypothyroidism (HT) emerges as a potential risk factor for OHSS occurrence. This review presented a comprehensive summary of pertinent case reports involving patients diagnosed with both HT and OHSS. Detailed exploration was conducted into their clinical presentations, diagnostic methodologies, and treatment modalities. Additionally, the review delved into potential interaction mechanisms between HT and OHSS, encompassing various aspects including hormone levels. Moreover, management strategies for mitigating the risk of OHSS in HT patients were thoroughly reviewed and the importance of monitoring thyroid function in those experiencing OHSS was emphasized. This review indicated that the association between HT and OHSS, underscoring its multifaceted complexity. It could accentuate the ongoing necessity for rigorous research and clinical refinement to deepen our comprehension of this association and to bolster diagnostic and therapeutic methodologies for optimal patient care. In conclusion, this review offered valuable insights for future research directions and clinical practices for patients afflicted with OHSS and HT.


Subject(s)
Hypothyroidism , Ovarian Hyperstimulation Syndrome , Humans , Ovarian Hyperstimulation Syndrome/complications , Ovarian Hyperstimulation Syndrome/therapy , Ovarian Hyperstimulation Syndrome/etiology , Hypothyroidism/complications , Female , Risk Factors
9.
Nanomaterials (Basel) ; 14(9)2024 Apr 25.
Article in English | MEDLINE | ID: mdl-38727342

ABSTRACT

Thermoelectric power can convert heat and electricity directly and reversibly. Low-dimensional thermoelectric materials, particularly thin films, have been considered a breakthrough for separating electronic and thermal transport relationships. In this study, a series of Bi0.5Sb1.5Te3 thin films with thicknesses of 0.125, 0.25, 0.5, and 1 µm have been fabricated by RF sputtering for the study of thickness effects on thermoelectric properties. We demonstrated that microstructure (texture) changes highly correlate with the growth thickness in the films, and equilibrium annealing significantly improves the thermoelectric performance, resulting in a remarkable enhancement in the thermoelectric performance. Consequently, the 0.5 µm thin films achieve an exceptional power factor of 18.1 µWcm-1K-2 at 400 K. Furthermore, we utilize a novel method that involves exfoliating a nanosized film and cutting with a focused ion beam, enabling precise in-plane thermal conductivity measurements through the 3ω method. We obtain the in-plane thermal conductivity as low as 0.3 Wm-1K-1, leading to a maximum ZT of 1.86, nearing room temperature. Our results provide significant insights into advanced thin-film thermoelectric design and fabrication, boosting high-performance systems.

10.
Int J Med Robot ; 20(3): e2635, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38733580

ABSTRACT

BACKGROUND: Rotational alignment in total knee arthroplasty (TKA) is a crucial technical point that needs attention. We conducted a retrospective study to investigate whether a new robot-assisted TKA (RA-TKA) could improve the accuracy of rotational alignment and whether rotational alignment affects postoperative pain and functional evaluation of the knee. METHODS: A total of 136 consecutive patients who underwent TKA were included in this study. Half of the patients underwent RA-TKA and the other half underwent conventional TKA (CON-TKA) by the same group of surgeons. Collect the relevant parameters. RESULTS: The postoperative femoral rotation angle (FRA) was -0.72 ± 2.59° in the robot-assisted group and 1.13 ± 2.73° in the conventional group, and were statistically significantly different (p < 0.001). CONCLUSION: This study provides preliminary evidence that the RA-TKA provides more precise control of FRA than CON-TKA, and verifies that tibial rotation angle and combined rotation angle affect postoperative knee pain and functional evaluation.


Subject(s)
Arthroplasty, Replacement, Knee , Femur , Robotic Surgical Procedures , Humans , Arthroplasty, Replacement, Knee/methods , Robotic Surgical Procedures/methods , Retrospective Studies , Female , Male , Aged , Middle Aged , Rotation , Femur/surgery , Knee Joint/surgery , Knee Joint/physiopathology , Range of Motion, Articular , Pain, Postoperative/prevention & control , Pain, Postoperative/etiology , Treatment Outcome
11.
PeerJ ; 12: e17272, 2024.
Article in English | MEDLINE | ID: mdl-38699187

ABSTRACT

Background: Esophageal squamous cell carcinoma (ESCC) is highly prevalent and has a high mortality rate. Traditional diagnostic methods, such as imaging examinations and blood tumor marker tests, are not effective in accurately diagnosing ESCC due to their low sensitivity and specificity. Esophageal endoscopic biopsy, which is considered as the gold standard, is not suitable for screening due to its invasiveness and high cost. Therefore, this study aimed to develop a convenient and low-cost diagnostic method for ESCC using plasma-based lipidomics analysis combined with machine learning (ML) algorithms. Methods: Plasma samples from a total of 40 ESCC patients and 31 healthy controls were used for lipidomics study. Untargeted lipidomics analysis was conducted through liquid chromatography-mass spectrometry (LC-MS) analysis. Differentially expressed lipid features were filtered based on multivariate and univariate analysis, and lipid annotation was performed using MS-DIAL software. Results: A total of 99 differential lipids were identified, with 15 up-regulated lipids and 84 down-regulated lipids, suggesting their potential as diagnostic targets for ESCC. In the single-lipid plasma-based diagnostic model, nine specific lipids (FA 15:4, FA 27:1, FA 28:7, FA 28:0, FA 36:0, FA 39:0, FA 42:0, FA 44:0, and DG 37:7) exhibited excellent diagnostic performance, with an area under the curve (AUC) exceeding 0.99. Furthermore, multiple lipid-based ML models also demonstrated comparable diagnostic ability for ESCC. These findings indicate plasma lipids as a promising diagnostic approach for ESCC.


Subject(s)
Biomarkers, Tumor , Esophageal Neoplasms , Esophageal Squamous Cell Carcinoma , Lipidomics , Humans , Esophageal Squamous Cell Carcinoma/blood , Esophageal Squamous Cell Carcinoma/diagnosis , Esophageal Neoplasms/blood , Esophageal Neoplasms/diagnosis , Male , Lipidomics/methods , Female , Biomarkers, Tumor/blood , Retrospective Studies , Middle Aged , Aged , Machine Learning , Lipids/blood , Chromatography, Liquid , Case-Control Studies
12.
Sci Rep ; 14(1): 10523, 2024 May 08.
Article in English | MEDLINE | ID: mdl-38719833

ABSTRACT

Featuring low power loss and high reliability, voltage source converter medium voltage direct current (VSC-MVDC) systems have been widely employed for grid-tied renewable energy applications. To maintain high operational safety, circuit breakers are needed to isolate faulted powerlines by comprehensively considering response speed and installation cost. Research efforts have been put to realizing DC fault isolation by coordinating resistive type superconducting fault current limiter (R-SFCL) and integrated-gate-commutated-thyristor (IGCT) based hybrid DC circuit breaker. In this paper, a controllable current commutation based superconducting DC circuit breaker (CCCB-SDCCB) is proposed. By integrating R-SFCL with IGCT based hybrid DC circuit breakers, the current interrupting capacity can be greatly enlarged with the advantage of low cost and fast speed, and hence the overall cost for suppress large fault currents can be greatly reduced for MVDC systems. In addition, a new current injection circuit branch using H-bridge structure is designed to recycle the residual capacitor voltage from the previous fault stage to trigger the IGCTs without the capacitor pre-charging process. Simulation results show that the fault current can be successfully suppressed from 24.2 to 2.1 kA and fully interrupted within 4.11 ms by the proposed CCCB-SDCCB.

13.
PeerJ ; 12: e17395, 2024.
Article in English | MEDLINE | ID: mdl-38784392

ABSTRACT

Objective: We compared the effects of early and delayed rehabilitation on the function of patients after rotator cuff repair by meta-analysis to find effective interventions to promote the recovery of shoulder function. Methods: This meta-analysis was registered in PROSPERO (CRD42023466122). We manually searched the randomized controlled trials (RCTs) in the Cochrane Library, Pubmed, Cochrane Library, EMBASE, the China National Knowledge Infrastructure (CNKI), the China VIP Database (VIP), and the Wanfang Database to evaluate the effect of early and delayed rehabilitation after arthroscopic shoulder cuff surgery on the recovery of shoulder joint function. Review Manager 5.3 software was used to analyze the extracted data. Then, the PEDro scale was employed to appraise the methodological quality of the included research. Results: This research comprised nine RCTs and 830 patients with rotator cuff injuries. According to the findings of the meta-analysis, there was no discernible difference between the early rehabilitation group and the delayed rehabilitation group at six and twelve months after the surgery in terms of the VAS score, SST score, follow-up rotator cuff healing rate, and the rotator cuff retear rate at the final follow-up. There was no difference in the ASES score between the early and delayed rehabilitation groups six months after the operation. However, although the ASES score in the early rehabilitation group differed significantly from that in the delayed rehabilitation group twelve months after the operation, according to the analysis of the minimal clinically important difference (MCID), the results have no clinical significance. Conclusions: The improvement in shoulder function following arthroscopic rotator cuff surgery does not differ clinically between early and delayed rehabilitation. When implementing rehabilitation following rotator cuff repair, it is essential to consider the paradoxes surrounding shoulder range of motion and tendon anatomic healing. A program that allows for flexible progression based on the patient's ability to meet predetermined clinical goals or criteria may be a better option.


Subject(s)
Arthroscopy , Recovery of Function , Rotator Cuff Injuries , Humans , Arthroscopy/rehabilitation , Rotator Cuff Injuries/surgery , Rotator Cuff Injuries/rehabilitation , Rotator Cuff/surgery , Range of Motion, Articular , Time Factors , Randomized Controlled Trials as Topic , Treatment Outcome
14.
Entropy (Basel) ; 26(5)2024 Apr 23.
Article in English | MEDLINE | ID: mdl-38785601

ABSTRACT

Supervised learning methods excel in traditional relation extraction tasks. However, the quality and scale of the training data heavily influence their performance. Few-shot relation extraction is gradually becoming a research hotspot whose objective is to learn and extract semantic relationships between entities with only a limited number of annotated samples. In recent years, numerous studies have employed prototypical networks for few-shot relation extraction. However, these methods often suffer from overfitting of the relation classes, making it challenging to generalize effectively to new relationships. Therefore, this paper seeks to utilize a diffusion model for data augmentation to address the overfitting issue of prototypical networks. We propose a diffusion model-enhanced prototypical network framework. Specifically, we design and train a controllable conditional relation generation diffusion model on the relation extraction dataset, which can generate the corresponding instance representation according to the relation description. Building upon the trained diffusion model, we further present a pseudo-sample-enhanced prototypical network, which is able to provide more accurate representations for prototype classes, thereby alleviating overfitting and better generalizing to unseen relation classes. Additionally, we introduce a pseudo-sample-aware attention mechanism to enhance the model's adaptability to pseudo-sample data through a cross-entropy loss, further improving the model's performance. A series of experiments are conducted to prove our method's effectiveness. The results indicate that our proposed approach significantly outperforms existing methods, particularly in low-resource one-shot environments. Further ablation analyses underscore the necessity of each module in the model. As far as we know, this is the first research to employ a diffusion model for enhancing the prototypical network through data augmentation in few-shot relation extraction.

15.
Nature ; 629(8013): 784-790, 2024 May.
Article in English | MEDLINE | ID: mdl-38720075

ABSTRACT

Electro-optical photonic integrated circuits (PICs) based on lithium niobate (LiNbO3) have demonstrated the vast capabilities of materials with a high Pockels coefficient1,2. They enable linear and high-speed modulators operating at complementary metal-oxide-semiconductor voltage levels3 to be used in applications including data-centre communications4, high-performance computing and photonic accelerators for AI5. However, industrial use of this technology is hindered by the high cost per wafer and the limited wafer size. The high cost results from the lack of existing high-volume applications in other domains of the sort that accelerated the adoption of silicon-on-insulator (SOI) photonics, which was driven by vast investment in microelectronics. Here we report low-loss PICs made of lithium tantalate (LiTaO3), a material that has already been adopted commercially for 5G radiofrequency filters6 and therefore enables scalable manufacturing at low cost, and it has equal, and in some cases superior, properties to LiNbO3. We show that LiTaO3 can be etched to create low-loss (5.6 dB m-1) PICs using a deep ultraviolet (DUV) stepper-based manufacturing process7. We demonstrate a LiTaO3 Mach-Zehnder modulator (MZM) with a half-wave voltage-length product of 1.9 V cm and an electro-optic bandwidth of up to 40 GHz. In comparison with LiNbO3, LiTaO3 exhibits a much lower birefringence, enabling high-density circuits and broadband operation over all telecommunication bands. Moreover, the platform supports the generation of soliton microcombs. Our work paves the way for the scalable manufacture of low-cost and large-volume next-generation electro-optical PICs.


Subject(s)
Lithium , Oxides , Photons , Lithium/chemistry , Oxides/chemistry , Tantalum/chemistry , Niobium/chemistry , Semiconductors , Optics and Photonics/instrumentation , Ultraviolet Rays , Silicon/chemistry
16.
Environ Pollut ; 354: 124178, 2024 May 17.
Article in English | MEDLINE | ID: mdl-38763294

ABSTRACT

Cadmium (Cd) pollution has been a significant concern in heavy metal pollution, prompting plants to adopt various strategies to mitigate its damage. While the response of plants to Cd stress and the impact of exogenous melatonin has received considerable attention, there has been limited focus on the responses of closely related species to these factors. Consequently, our investigation aimed to explore the response of three different species of rape to Cd stress and examine the influence of exogenous melatonin in this scenario. The research findings revealed distinctive responses among the investigated rape species. B. campestris showed the resistance to Cd and exhibited lower Cd absorption and sustained its physiological activity under Cd stress. In contrast, B. juncea accumulated much Cd and increased the amount of anthocyanin to mitigate the Cd-damage. Furthermore, B. napus showed the tolerance to Cd and tended to accumulate Cd in vacuoles under Cd stress, thereby decreasing the Cd damage and leading to higher activity of antioxidant enzymes and photosynthesis. Moreover, the application of exogenous melatonin significantly elevated the melatonin level in plants and mitigated Cd toxicity by promoting the activity of antioxidant enzymes, reducing Cd absorption, enhancing the chelating capacity with Cd, decreasing Cd accumulation in organelles, and reducing its fluidity. Specifically, exogenous melatonin increased the FHAc content in B. campestris, elevated the phytochelatins (PCs) level in B. napus, and stimulated photosynthesis in B. juncea. In summary, the findings underscore the species-specific responses of the three species of rape to both Cd stress and exogenous melatonin, highlighting the potential for tailored mitigation strategies based on the unique characteristics of each species.

17.
ACS Nano ; 18(19): 12560-12568, 2024 May 14.
Article in English | MEDLINE | ID: mdl-38700899

ABSTRACT

Spin in semiconductors facilitates magnetically controlled optoelectronic and spintronic devices. In metal halide perovskites (MHPs), doping magnetic ions is proven to be a simple and efficient approach to introducing a spin magnetic momentum. In this work, we present a facile metal ion doping protocol through the vapor-phase metal halide insertion reaction to the chemical vapor deposition (CVD)-grown ultrathin Cs3BiBr6 perovskites. The Fe-doped bismuth halide (Fe:CBBr) perovskites demonstrate that the iron spins are successfully incorporated into the lattice, as revealed by the spin-phonon coupling below the critical temperature Tc around 50 K observed through temperature-dependent Raman spectroscopy. Furthermore, the phonons exhibit significant softening under an applied magnetic field, possibly originating from magnetostriction and spin exchange interaction. The spin-phonon coupling in Fe:CBBr potentially provides an efficient way to tune the spin and lattice parameters for halide perovskite-based spintronics.

18.
Article in English | MEDLINE | ID: mdl-38780218

ABSTRACT

BACKGROUND: Diabetes, a chronic condition affecting various organs, is frequently associated with abnormal lipid metabolism, notably increased cholesterol and triglyceride levels. These lipid abnormalities are closely linked to the development and advancement of cardiovascular disease (CVD). Although regular physical activity (PA) has consistently shown benefits in reducing CVD risk in the general population, its precise influence on CVD risk among diabetic patients remains uncertain, particularly regarding dose-response relationships. OBJECTIVE: This study aimed to summarize the evidence from prospective studies on the association between PA and CVD morbidity and mortality in individuals with diabetes, and to explore the optimal levels for public health recommendation. METHODS: We systematically reviewed prospective cohort studies in PubMed, EMBASE, and Web of Science up to December 2022, with inclusion criteria specifying the studies published in English and included adult participants diagnosed with diabetes. A random-effects model was used to pool the relative risk (RR) with the corresponding 95% confidence interval (CI) comparing the highest with the lowest PA categories in each study for qualitative evaluation. In addition, linear and spline regression analyses were used to estimate dose-response associations. RESULTS: The meta-analysis included 12 prospective cohort studies, involving a total of 109,820 participants with diabetes. The combined results revealed that higher levels of PA were associated with a reduced risk of CVD. The RR of CVD for the highest compared with the lowest PA category was 0.62 (95% CI, 0.51-0.73). In addition, there were four studies describing leisure-time physical activity (LTPA) and the pooled RR was 0.68 (95% CI, 0.52-0.83) for the highest versus the lowest activity. The linear regression model revealed that each 10 MET-h/week of incrementally higher PA was associated with a 19.0% (95% CI, 11.6%-25.7%) and a 6.9% (95% CI, 4.5%-9.3%) reduction in CVD morbidity and mortality. Additionally, spline regression curves showed nonlinear relationships between PA levels and the risk of CVD and CVD mortality (both P-nonlinearity <0.001), with a limited reduction in CVD risk and some further reduction in CVD mortality above 20 MET-h per week of PA levels. CONCLUSIONS: For patients with diabetes, especially type 2 diabetes, there was a dose-response relationship between increased PA and reduced risk of CVD morbidity and mortality. The observed PA threshold is consistent with the recommended level for the general population. Gradually moving from inactivity to a guideline-recommended PA level could therefore significantly reduce the burden of CVD in patients with diabetes.

19.
J Phys Chem B ; 128(19): 4728-4734, 2024 May 16.
Article in English | MEDLINE | ID: mdl-38693711

ABSTRACT

The Mn4CaO5 cluster, featuring four ligand water molecules (W1 to W4), serves as the water-splitting site in photosystem II (PSII). X-ray free electron laser (XFEL) structures exhibit an additional oxygen site (O6) adjacent to the O5 site in the fourth lowest oxidation state, S3, forming Mn4CaO6. Here, we investigate the mechanism of the second water ligand molecule at the dangling Mn (W2) as a potential incorporating species, using a quantum mechanical/molecular mechanical (QM/MM) approach. Previous QM/MM calculations demonstrated that W1 releases two protons through a low-barrier H-bond toward D1-Asp61 and subsequently releases an electron during the S2 to S3 transition, resulting in O•- at W1 and protonated D1-Asp61. During the process of Mn4CaO6 formation, O•-, rather than H2O or OH-, best reproduced the O5···O6 distance. Although the catalytic cluster with O•- at O6 is more stable than that with O•- at W1 in S3, it does not occur spontaneously due to the significantly uphill deprotonation process. Assuming O•- at W2 incorporates into the O6 site, an exergonic conversion from Mn1(III)Mn2(IV)Mn3(IV)Mn4(IV) (equivalent to the open-cubane S2 valence state) to Mn1(IV)Mn2(IV)Mn3(IV)Mn4(III) (equivalent to the closed-cubane S2 valence state) occurs. These findings provide energetic insights into the deprotonation and structural conversion events required for the Mn4CaO6 formation.

20.
Chemosphere ; 359: 142262, 2024 May 05.
Article in English | MEDLINE | ID: mdl-38714252

ABSTRACT

Industrialization has caused a significant global issue with cadmium (Cd) pollution. In this study, Biochar (Bc), generated through initial pyrolysis of rice straw, underwent thorough mixing with magnetized bentonite clay, followed by activation with KOH and subsequent pyrolysis. Consequently, a magnetized bentonite modified rice straw biochar (Fe3O4@B-Bc) was successfully synthesized for effective treatment and remediation of this problem. Fe3O4@B-Bc not only overcomes the challenges associated with the difficult separation of individual bentonite or biochar from water, but also exhibited a maximum adsorption capacity of Cd(II) up to 241.52 mg g-1. The characterization of Fe3O4@B-Bc revealed that its surface was rich in C, O and Fe functional groups, which enable efficient adsorption. The quantitative calculation of the contribution to the adsorption mechanism indicates that cation exchange and physical adsorption accounted for 65.87% of the total adsorption capacity. In conclusion, Fe3O4@B-Bc can be considered a low-cost and recyclable green adsorbent, with broad potential for treating cadmium-polluted water.

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