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NMR in Biomedicine Jul 2024Transmembrane water permeability changes occur after initialization of necrosis and are a mechanism for early detection of cell death. Filter-exchange spectroscopy...
Transmembrane water permeability changes occur after initialization of necrosis and are a mechanism for early detection of cell death. Filter-exchange spectroscopy (FEXSY) is sensitive to transmembrane water permeability and enables its quantification by magnetic resonance via the apparent exchange rate (AXR). In this study, we investigate AXR changes during necrotic cell death. FEXSY measurements of yeast cells in different necrotic stages were performed and compared with established fluorescence cell death markers and pulsed gradient spin echo measurements. Furthermore, the influence of T2 relaxation on AXR was examined in a two-compartment system. The AXR of yeast cells increased slightly after incubation with 20% isopropanol, whereas it peaked sharply after incubation with 25% isopropanol. At this point, almost all the yeast cells were vital but showed compromised membranes. After incubation with 30% isopropanol, AXR measurements showed high variability, at a point corresponding to a majority of the yeast cells being in late-stage necrosis with disrupted cell membranes. Simulations revealed that, for FEXSY measurements in a two-compartment system, a long filter echo time (TE), compared with the T2 of the slow-diffusing compartment, filters out a fraction of the slow-diffusing compartment signal and leads to overestimation of apparent diffusion coefficient (ADC) and underestimation of AXR. Our results demonstrate that AXR is sensitive to gradual permeabilization of the cell membrane of living cells in different permeabilization stages without exogenous contrast agents. AXR measurements were sensitive to permeability changes induced by relatively low concentrations of isopropanol, at levels for which no measurable effect was detectable by ADC measurements. TE may act as a signal filter that affects the estimated AXR value of a system consisting of a variety of local diffusivities and a range of T2 that includes T2 values shorter or comparable with the TE.
PubMed: 38953779
DOI: 10.1002/nbm.5202 -
Inorganic Chemistry Jul 2024Rechargeable aqueous zinc-ion batteries (AZIBs) have developed into one of the most attractive materials for large-scale energy storage owing to their advantages such as...
Rechargeable aqueous zinc-ion batteries (AZIBs) have developed into one of the most attractive materials for large-scale energy storage owing to their advantages such as high energy density, low cost, and environmental friendliness. Nevertheless, the sluggish diffusion kinetics and inherent impoverished conductivity affect their practical application. Herein, the β-MnO composited with carbon nanotubes (CNT@M) is prepared through a simple hydrothermal approach as a high-performance cathode for AZIBs. The CNT@M electrode exhibits excellent cycling stability, in which the maximum specific discharge capacity is 259 mA h g at 3 A g, and there is still 220 mA h g after 2000 cycles. The specific capacity is obviously better than that of β-MnO (32 mA h g after 2000 cycles). The outstanding electrochemical performance of the battery is inseparable from the structural framework of CNT and inherent high conductivity. Furthermore, CNT@M can form a complex conductive network based on CNTs to provide excellent ion diffusion and charge transfer. Therefore, the active material can maintain a long-term cycle and achieve stable capacity retention. This research provides a reasonable solution for the reliable conception of Mn-based electrodes and indicates its potential application in high-performance AZIB cathode materials.
PubMed: 38953738
DOI: 10.1021/acs.inorgchem.4c02290 -
The Journal of Physical Chemistry... Jul 2024Our study has effectively employed electrophoretic deposition (EPD) using AC voltage to develop a lithium iron phosphate (LFP) Li-ion battery featuring pseudocapacitive...
Our study has effectively employed electrophoretic deposition (EPD) using AC voltage to develop a lithium iron phosphate (LFP) Li-ion battery featuring pseudocapacitive properties and improved high C-rate performance. This method has significantly improved the battery's specific capacity, achieving an impressive 100 mAhg-1 at a 5 C discharge rate, which showcases its superior high-rate capability. Additionally, the battery displayed excellent reversibility during its performance cycles. These results confirm the EPD method's efficacy in improving LFP electrode performance, yielding notable improvements in cycling stability and high-rate capability. The enhanced capacity and high-rate performance of the electrophoretic-deposited LFP electrodes are largely due to the fast kinetics facilitated by pseudocapacitive behavior-induced charge storage and a high Li-ion diffusion constant measured in our EPD-deposited LFP electrodes. This underscores the practicality of our approach and the development of a fundamental test platform to investigate the pseudocapacitive charge storage mechanism in electrodes with typical battery-like behavior.
PubMed: 38953624
DOI: 10.1021/acs.jpclett.4c01717 -
Journal of the American Chemical Society Jul 2024Van der Waals (vdW) magnets both allow exploration of fundamental 2D physics and offer a route toward exploiting magnetism in next generation information technology, but...
Van der Waals (vdW) magnets both allow exploration of fundamental 2D physics and offer a route toward exploiting magnetism in next generation information technology, but vdW magnets with complex, noncollinear spin textures are currently rare. We report here the syntheses, crystal structures, magnetic properties and magnetic ground states of four bulk vdW metal-organic magnets (MOMs): FeCl(pym), FeCl(btd), NiCl(pym), and NiCl(btd), pym = pyrimidine and btd = 2,1,3-benzothiadiazole. Using a combination of neutron diffraction and bulk magnetometry we show that these materials are noncollinear magnets. Although only NiCl(btd) has a ferromagnetic ground state, we demonstrate that low-field hysteretic metamagnetic transitions produce states with net magnetization in zero-field and high coercivities for FeCl(pym) and NiCl(pym). By combining our bulk magnetic data with diffuse scattering analysis and broken-symmetry density-functional calculations, we probe the magnetic superexchange interactions, which when combined with symmetry analysis allow us to suggest design principles for future noncollinear vdW MOMs. These materials, if delaminated, would prove an interesting new family of 2D magnets.
PubMed: 38953583
DOI: 10.1021/jacs.4c04102 -
Network (Bristol, England) Jul 2024Groundnut is a noteworthy oilseed crop. Attacks by leaf diseases are one of the most important reasons causing low yield and loss of groundnut plant growth, which will...
Groundnut is a noteworthy oilseed crop. Attacks by leaf diseases are one of the most important reasons causing low yield and loss of groundnut plant growth, which will directly diminish the yield and quality. Therefore, an Optimized Wasserstein Deep Convolutional Generative Adversarial Network fostered Groundnut Leaf Disease Identification System (GLDI-WDCGAN-AOA) is proposed in this paper. The pre-processed output is fed to Hesitant Fuzzy Linguistic Bi-objective Clustering (HFL-BOC) for segmentation. By using Wasserstein Deep Convolutional Generative Adversarial Network (WDCGAN), the input leaf images are classified into Healthy leaf, early leaf spot, late leaf spot, nutrition deficiency, and rust. Finally, the weight parameters of WDCGAN are optimized by Aquila Optimization Algorithm (AOA) to achieve high accuracy. The proposed GLDI-WDCGAN-AOA approach provides 23.51%, 22.01%, and 18.65% higher accuracy and 24.78%, 23.24%, and 28.98% lower error rate analysed with existing methods, such as Real-time automated identification and categorization of groundnut leaf disease utilizing hybrid machine learning methods (GLDI-DNN), Online identification of peanut leaf diseases utilizing the data balancing method along deep transfer learning (GLDI-LWCNN), and deep learning-driven method depending on progressive scaling method for the precise categorization of groundnut leaf infections (GLDI-CNN), respectively.
PubMed: 38953316
DOI: 10.1080/0954898X.2024.2351146 -
Advanced Science (Weinheim,... Jul 2024The extracellular matrix (ECM) is critical for drug resistance in colorectal cancer (CRC). The abundant collagen within the ECM significantly influences tumor...
The extracellular matrix (ECM) is critical for drug resistance in colorectal cancer (CRC). The abundant collagen within the ECM significantly influences tumor progression and matrix-mediated drug resistance (MMDR) by binding to discoidin domain receptor 1 (DDR1), but the specific mechanisms by which tumor cells modulate ECM via DDR1 and ultimately regulate TME remain poorly understand. Furthermore, overcoming drug resistance by modulating the tumor ECM remains a challenge in CRC treatment. In this study, a novel mechanism is elucidated by which DDR1 mediates the interactions between tumor cells and collagen, enhances collagen barriers, inhibits immune infiltration, promotes drug efflux, and leads to MMDR in CRC. To address this issue, a multistage drug delivery system carrying DDR1-siRNA and chemotherapeutic agents is employed to disrupt collagen barriers by silencing DDR1 in tumor, enhancing chemotherapy drugs diffusion and facilitating immune infiltration. These findings not only revealed a novel role for collagen-rich matrix mediated by DDR1 in tumor resistance, but also introduced a promising CRC treatment strategy.
PubMed: 38953306
DOI: 10.1002/advs.202402107 -
ACS Applied Materials & Interfaces Jul 2024Li-rich layered oxide cathodes have attracted extensive attention due to their high energy density. However, due to the low initial Coulombic efficiency and the capacity...
Li-rich layered oxide cathodes have attracted extensive attention due to their high energy density. However, due to the low initial Coulombic efficiency and the capacity fading and voltage fading during cycling, its practical application is still a great challenge. Here, we report the one-step realization of layered/spinel heterostructures and Na doping by the sodium dodecyl sulfate (SDS)-assisted sol-gel method. The spinel phase provides 3D diffusion channels for Li-ions, and sodium doping changes the layered lattice constant and expands the layer spacing. Therefore, the designed LiMnNiCoNaO (SDS-2) cathode possesses excellent electrochemical performance such as higher initial Coulombic efficiency and rate capacity and also alleviates voltage decay. The initial discharge-specific capacity of SDS-2 is 298.8 mAh g at 0.1 C, and the discharge-specific capacity can reach 111.7 mAh g at 10 C. This strategy can provide new insights into the design and synthesis of high-performance Li-rich layered oxide cathode materials.
PubMed: 38953275
DOI: 10.1021/acsami.4c04281 -
Pediatric Blood & Cancer Jul 2024
PubMed: 38953145
DOI: 10.1002/pbc.31122 -
Cureus May 2024Acute appendicitis is the most common non-obstetric reason for exploratory laparotomy during pregnancy. This case report involves a primigravida patient who presented to...
Early Diagnosis of Acute Appendicitis in the Second Trimester of Pregnancy Based on Non-typical Clinical Findings: Report of a Rare Case and a Mini-Review of the Literature.
Acute appendicitis is the most common non-obstetric reason for exploratory laparotomy during pregnancy. This case report involves a primigravida patient who presented to the emergency department of the General Hospital of Trikala at 15 weeks of gestation due to diffuse abdominal pain, primarily in the epigastric region. She also reported watery bowel movements. The ongoing atypical clinical symptoms, along with elevated inflammatory markers, strongly indicated a diagnosis of acute appendicitis. An immediate exploratory laparotomy was performed, during which acute localized inflammation of the appendix was found, leading to an appendectomy. Histological examination confirmed the diagnosis of acute appendicitis. The patient reported pain relief immediately after the surgery. On the fourth postoperative day, she was discharged without any signs of a threatened second-trimester miscarriage. At 39 gestational weeks, she delivered by elective cesarean section due to breech presentation. This paper discusses the case and highlights the significant challenges in the early diagnosis and management of acute appendicitis during pregnancy, emphasizing the importance of preventing potentially life-threatening complications for both the mother and the fetus.
PubMed: 38953065
DOI: 10.7759/cureus.61463 -
Nigerian Medical Journal : Journal of... 2023The use of antenatal corticosteroids beyond 34 weeks of gestation to prevent certain neonatal complications remains a debate. This study sought to determine the effect...
BACKGROUND
The use of antenatal corticosteroids beyond 34 weeks of gestation to prevent certain neonatal complications remains a debate. This study sought to determine the effect of the use of antenatal corticosteroids in late preterm delivery on neonatal morbidity.
METHODOLOGY
It was a randomized double-blind placebo and active-controlled multi-arm trial. There were two study groups and one control group. It was conducted at the Department of Obstetrics and Gynaecology and the Department of Paediatrics of Ahmadu Bello University Teaching Hospital Zaria, Nigeria. Pregnant women at 34 weeks to 36 weeks 6 days of gestation scheduled for elective delivery or who had emergency delivery were recruited for the study. The first study group had 2 doses of 12mg intramuscular dexamethasone and the second study group had 2 doses of 12mg betamethasone. The control group had 2 doses of a placebo. The primary outcome was the incidence of respiratory distress syndrome evidenced by tachypnoea with grunting, recession, or nasal flaring with diffuse reticulogranular infiltrate on X-ray or respiratory distress requiring the need for respiratory support by 72 hours of age. Secondary outcome measures included the need for neonatal resuscitation at birth, admission into the Special Care Baby Unit/Neonatal Intensive Care Unit, transient tachypnoea of the newborn, and apnoea.
RESULTS
A total of 138 mothers and 146 preterm neonates were included. A pairwise analysis was done to test for differences between the groups. There was no difference in the incidence of respiratory distress syndrome between the groups. However, the need for neonatal resuscitation was significantly higher (RR: 7.0; CI: 2.49-19.4; p = <0.001) in the placebo group when compared to the betamethasone group and also significantly higher (RR:4.0; CI: 1.86-26.03; p= 0.01) in the placebo group when compared to the dexamethasone group.
CONCLUSION
Antenatal corticosteroids may decrease the need for neonatal resuscitation at birth in late preterm neonates.
FUNDING
The research was funded by the Tertiary Education Trust Fund (TETFUND) of Nigeria. Trial registration: ClinicalTrial.gov, NCT03446937.
PubMed: 38952884
DOI: 10.60787/NMJ-64-4-297