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Scientific Reports Jun 2024Worldwide industrialization has grown at a rapid pace, contaminating water resources, particularly with phenolic pollutants that pose a risk to aquatic systems and human...
Worldwide industrialization has grown at a rapid pace, contaminating water resources, particularly with phenolic pollutants that pose a risk to aquatic systems and human health. The goal of this study is to create an inexpensive magnetic composite that can effectively remove nitrophenol (o-NP) using adsorptive means. In this instance, a nonanyl chitosan (N-Cs) derivative was synthesized and then combined with activated petroleum coke (AP-coke) and magnetic FeO to boost its adsorbability towards o-NP and to facilitate its separation. Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), X-ray diffractometer (XRD), Vibrating sample magnetometer (VSM), X-ray photoelectron spectroscopy (XPS), and zeta potential were employed to characterize the magnetic composite. The experimental results indicated that the FeO/AP-coke/N-Cs composite possesses a greater affinity toward o-NP with a maximal efficiency reached 88% compared to 22.8, 31.2, and 45.8% for FeO, AP-coke and N-Cs, respectively. The equilibrium adsorption data coincided with the Langmuir, Freundlich, and Temkin isotherm models, with a maximum adsorption capacity of 291.55 mg/g at pH 6, whereas the pseudo second order kinetic model offered the best fit to the experimental data. Besides, the developed adsorbent preserved satisfactory adsorption characteristics after reuse for five successive cycles. The proposed adsorption mechanism involves the H-bonding, π-π interaction, hydrophobic interactions and electron donor-acceptor interactions. These findings hypothesize that the constructed magnetic composite could efficiently remove nitrophenols from polluted water with high performance and ease-separation.
PubMed: 38914588
DOI: 10.1038/s41598-024-64117-1 -
Nature Communications Jun 2024Quantum fluctuations in low-dimensional systems and near quantum phase transitions have significant influences on material properties. Yet, it is difficult to...
Quantum fluctuations in low-dimensional systems and near quantum phase transitions have significant influences on material properties. Yet, it is difficult to experimentally gauge the strength and importance of quantum fluctuations. Here we provide a resonant inelastic x-ray scattering study of magnon excitations in Mott insulating cuprates. From the thin film of SrCuO, single- and bi-magnon dispersions are derived. Using an effective Heisenberg Hamiltonian generated from the Hubbard model, we show that the single-magnon dispersion is only described satisfactorily when including significant quantum corrections stemming from magnon-magnon interactions. Comparative results on LaCuO indicate that quantum fluctuations are much stronger in SrCuO suggesting closer proximity to a magnetic quantum critical point. Monte Carlo calculations reveal that other magnetic orders may compete with the antiferromagnetic Néel order as the ground state. Our results indicate that SrCuO-due to strong quantum fluctuations-is a unique starting point for the exploration of novel magnetic ground states.
PubMed: 38914556
DOI: 10.1038/s41467-024-49714-y -
Scientific Reports Jun 2024Nucleic acid amplification testing has great potential for point-of-need diagnostic testing with high detection sensitivity and specificity. Current sample preparation...
Nucleic acid amplification testing has great potential for point-of-need diagnostic testing with high detection sensitivity and specificity. Current sample preparation is limited by a tedious workflow requiring multiple steps, reagents and instrumentation, hampering nucleic acid testing at point of need. In this study, we present the use of mixed cellulose ester (MCE) paper for DNA binding by ionic interaction under molecular crowding conditions and fluid transport by wicking. The poly(ethylene) glycol-based (PEG) reagent simultaneously provides the high pH for alkaline lysis and crowding effects for ionic binding of the DNA under high salt conditions. In this study, we introduce Paper-based Abridged Solid-Phase Extraction with Alkaline Poly(ethylene) Glycol Lysis (PASAP). The anionic mixed cellulose ester (MCE) paper is used as solid phase and allows for fluid transport by wicking, eliminating the need for pipetting skills and the use of a magnet to retain beads. Following the release of DNA from the cells due to the lytic activity of the PASAP solution, the DNA binds to the anionic surface of the MCE paper, concentrating at the bottom while the sample matrix is transported towards the top by wicking. The paper was washed by dipping it in 40% isopropanol for 10 s. After air-drying for 30 s, the bottom section of the paper (3 mm × 4 mm) was snapped off using the cap of a PCR tube and immersed in the colourimetric loop-mediated isothermal amplification (cLAMP) solution for direct amplification and colourimetric detection. The total sample processing was completed in 15 min and ready for amplification. cLAMP enabled the detection of 10 CFU/mL of Escherichia coli (E. coli) from culture media and the detection of E. coli in milk < 10 CFU/mL (10 CFU) after incubation at 68 °C for 60 min, demonstrating applicability of the method to complex biological samples.
Topics: Nucleic Acid Amplification Techniques; Paper; Colorimetry; DNA; Solid Phase Extraction; Polyethylene Glycols; DNA, Bacterial; Molecular Diagnostic Techniques
PubMed: 38914553
DOI: 10.1038/s41598-024-59763-4 -
Nature Communications Jun 2024Advancements in materials synthesis have been key to unveil the quantum nature of electronic properties in solids by providing experimental reference points for a...
Advancements in materials synthesis have been key to unveil the quantum nature of electronic properties in solids by providing experimental reference points for a correct theoretical description. Here, we report hidden transport phenomena emerging in the ultraclean limit of the archetypical correlated electron system SrVO. The low temperature, low magnetic field transport was found to be dominated by anisotropic scattering, whereas, at high temperature, we find a yet undiscovered phase that exhibits clear deviations from the expected Landau Fermi liquid, which is reminiscent of strange-metal physics in materials on the verge of a Mott transition. Further, the high sample purity enabled accessing the high magnetic field transport regime at low temperature, which revealed an anomalously high Hall coefficient. Taken with the strong anisotropic scattering, this presents a more complex picture of SrVO that deviates from a simple Landau Fermi liquid. These hidden transport anomalies observed in the ultraclean limit prompt a theoretical reexamination of this canonical correlated electron system beyond the Landau Fermi liquid paradigm, and more generally serves as an experimental basis to refine theoretical methods to capture such nontrivial experimental consequences emerging in correlated electron systems.
PubMed: 38914537
DOI: 10.1038/s41467-024-48043-4 -
Sheng Wu Gong Cheng Xue Bao = Chinese... Jun 2024Stimuli-responsive liposomes, a novel type of nanocarriers, have been widely used in the fields of medicine, food, and cosmetics. This paper provides a comprehensive... (Review)
Review
Stimuli-responsive liposomes, a novel type of nanocarriers, have been widely used in the fields of medicine, food, and cosmetics. This paper provides a comprehensive introduction to the preparation methods, construction strategies, and biological applications of stimuli-responsive liposomes. The review highlights the functional principles of pH-sensitive, redox-sensitive, enzyme-sensitive, heat-sensitive, light-sensitive, and magnetic field-responsive liposomes, and summarizes their applications based on various drug delivery mode. Finally, the article provides an overview of the current challenges and future development prospects for stimuli-responsive liposomes.
Topics: Liposomes; Drug Delivery Systems; Hydrogen-Ion Concentration; Drug Carriers; Oxidation-Reduction
PubMed: 38914489
DOI: 10.13345/j.cjb.230747 -
Journal of Neurosurgery. Case Lessons Jun 2024Spinal extradural arachnoid cysts (SEACs) communicate with the subarachnoid space through small communicating dural holes. The precise preoperative detection of all...
Successful detection of multiple communicating holes in multiple spinal extradural arachnoid cysts by using time-spatial labeling inversion pulse magnetic resonance imaging: illustrative case.
BACKGROUND
Spinal extradural arachnoid cysts (SEACs) communicate with the subarachnoid space through small communicating dural holes. The precise preoperative detection of all communicating holes, followed by minimally invasive dural closure, is the ideal treatment to prevent postoperative spinal deformities, especially in cases of multiple SEACs. However, standard imaging methods often fail to detect communicating hole locations. Although a few cases of successful single-hole detection via cinematic magnetic resonance imaging (MRI) have been reported, this modality's ability to detect multiple holes has not been demonstrated.
OBSERVATIONS
The authors describe the case of a 14-year-old male with myelopathy due to multiple SEACs at T5-8 and T8-12. Myelography revealed a complete block at the T8 level; no cephalic cyst or communicating holes were identified. Time-spatial labeling inversion pulse (T-SLIP) MRI revealed cerebrospinal fluid flow into the cyst at T10 and T7. A limited laminectomy or hemilaminectomy was performed at T7 and T10, and two dural holes were closed without a total cystectomy. The patient's gait disturbance and rectal disorder disappeared. The cysts were confirmed to have completely disappeared on conventional MRI at 1 year postoperatively.
LESSONS
T-SLIP MRI, a cinematic MRI, is useful for detecting multiple communicating holes in SEACs.
PubMed: 38914022
DOI: 10.3171/CASE24200 -
PloS One 2024With a globally aging population, there is a need to better understand how brain structure relates to function in healthy older and younger adults. (Comparative Study)
Comparative Study
OBJECTIVE
With a globally aging population, there is a need to better understand how brain structure relates to function in healthy older and younger adults.
METHODS
34 healthy participants divided into older (17; Mean = 70.9, SD = 5.4) and younger adults (17; Mean = 28.1, SD = 2.8) underwent diffusion-weighted imaging and neuropsychological assessment, including the California Verbal Learning Test 2nd Edition and the Trail Making Test (TMT-A and TMT-B). Differences in white matter microstructure for older and younger adults and the association between DTI metrics (fractional anisotropy, FA; mean diffusivity, MD) and cognitive performance were analyzed using tract-based spatial statistics (p < 0.05, corrected).
RESULTS
Older adults had significantly lower FA and higher MD than younger adults in widespread brain regions. There was a significant negative correlation between executive function (TMT-B) and MD for older adults in the right superior/anterior corona radiata and the corpus callosum. No significant relationship was detected between DTI metrics and executive function in younger adults or with memory performance in either group.
CONCLUSIONS
The findings underscore the need to examine brain-behaviour relationships as a function of age. Future studies should include comprehensive assessments in larger lifespan samples to better understand the aging brain.
Topics: Humans; White Matter; Aged; Male; Female; Adult; Neuropsychological Tests; Diffusion Tensor Imaging; Aging; Middle Aged; Executive Function; Cognition; Young Adult; Diffusion Magnetic Resonance Imaging; Brain; Aged, 80 and over; Anisotropy
PubMed: 38913655
DOI: 10.1371/journal.pone.0305818 -
PloS One 2024Motor issues are frequently observed accompanying core deficits in autism spectrum disorder (ASD). Impaired motor behavior has also been linked to cognitive and social...
Motor issues are frequently observed accompanying core deficits in autism spectrum disorder (ASD). Impaired motor behavior has also been linked to cognitive and social abnormalities, and problems with predictive ability have been suggested to play an important, possibly shared, part across all these domains. Brain imaging of sensory-motor behavior is a promising method for characterizing the neurobiological foundation for this proposed key trait. The present functional magnetic resonance imaging (fMRI) developmental study, involving children/youth with ASD, typically developing (TD) children/youth, and neurotypical adults, will investigate brain activations during execution and observation of a visually guided, goal-directed sequential (two-step) manual task. Neural processing related to both execution and observation of the task, as well as activation patterns during the preparation stage before execution/observation will be investigated. Main regions of interest include frontoparietal and occipitotemporal cortical areas, the human mirror neuron system (MNS), and the cerebellum.
Topics: Humans; Magnetic Resonance Imaging; Child; Brain; Male; Adolescent; Female; Adult; Brain Mapping; Autism Spectrum Disorder; Movement; Autistic Disorder; Young Adult; Psychomotor Performance; Mirror Neurons
PubMed: 38913636
DOI: 10.1371/journal.pone.0296225 -
ELife Jun 2024Downregulating emotional overreactions toward threats is fundamental for developing treatments for anxiety and post-traumatic disorders. The prefrontal cortex (PFC) is...
Downregulating emotional overreactions toward threats is fundamental for developing treatments for anxiety and post-traumatic disorders. The prefrontal cortex (PFC) is critical for top-down modulatory processes, and despite previous studies adopting repetitive transcranial magnetic stimulation (rTMS) over this region provided encouraging results in enhancing extinction, no studies have hitherto explored the effects of stimulating the medial anterior PFC (aPFC, encompassing the Brodmann area 10) on threat memory and generalization. Here we showed that rTMS over the aPFC applied before threat memory retrieval immediately decreases implicit reactions to learned and novel stimuli in humans. These effects enduringly persisted 1 week later in the absence of rTMS. No effects were detected on explicit recognition. Critically, rTMS over the aPFC resulted in a more pronounced reduction of defensive responses compared to rTMS targeting the dorsolateral PFC. These findings reveal a previously unexplored prefrontal region, the modulation of which can efficiently and durably inhibit implicit reactions to learned threats. This represents a significant advancement toward the long-term deactivation of exaggerated responses to threats.
Topics: Humans; Fear; Prefrontal Cortex; Transcranial Magnetic Stimulation; Male; Young Adult; Female; Adult; Extinction, Psychological
PubMed: 38913410
DOI: 10.7554/eLife.85951 -
ELife Jun 2024Allosteric cooperativity between ATP and substrates is a prominent characteristic of the cAMP-dependent catalytic subunit of protein kinase A (PKA-C). This long-range...
Allosteric cooperativity between ATP and substrates is a prominent characteristic of the cAMP-dependent catalytic subunit of protein kinase A (PKA-C). This long-range synergistic action is involved in substrate recognition and fidelity, and it may also regulate PKA's association with regulatory subunits and other binding partners. To date, a complete understanding of this intramolecular mechanism is still lacking. Here, we integrated NMR(Nuclear Magnetic Resonance)-restrained molecular dynamics simulations and a Markov State Model to characterize the free energy landscape and conformational transitions of PKA-C. We found that the apoenzyme populates a broad free energy basin featuring a conformational ensemble of the active state of PKA-C (ground state) and other basins with lower populations (excited states). The first excited state corresponds to a previously characterized inactive state of PKA-C with the αC helix swinging outward. The second excited state displays a disrupted hydrophobic packing around the regulatory (R) spine, with a flipped configuration of the F100 and F102 residues at the αC-β4 loop. We validated the second excited state by analyzing the F100A mutant of PKA-C, assessing its structural response to ATP and substrate binding. While PKA-C preserves its catalytic efficiency with Kemptide, this mutation rearranges the αC-β4 loop conformation, interrupting the coupling of the two lobes and abolishing the allosteric binding cooperativity. The highly conserved αC-β4 loop emerges as a pivotal element to control the synergistic binding of nucleotide and substrate, explaining how mutations or insertions near or within this motif affect the function and drug sensitivity in homologous kinases.
Topics: Molecular Dynamics Simulation; Allosteric Regulation; Adenosine Triphosphate; Catalytic Domain; Cyclic AMP-Dependent Protein Kinases; Protein Conformation; Protein Binding; Nucleotides; Substrate Specificity; Cyclic AMP-Dependent Protein Kinase Catalytic Subunits
PubMed: 38913408
DOI: 10.7554/eLife.91506