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1.
Magn Reson Med ; 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38576131

RESUMO

PURPOSE: Develop a true real-time implementation of MR signature matching (MRSIGMA) for free-breathing 3D MRI with sub-200 ms latency on the Elekta Unity 1.5T MR-Linac. METHODS: MRSIGMA was implemented on an external computer with a network connection to the MR-Linac. Stack-of-stars with partial kz sampling was used to accelerate data acquisition and ReconSocket was employed for simultaneous data transmission. Movienet network computed the 4D MRI motion dictionary and correlation analysis was used for signature matching. A programmable 4D MRI phantom was utilized to evaluate MRSIGMA with respect to a ground-truth translational motion reference. In vivo validation was performed on patients with pancreatic cancer, where 15 patients were employed to train Movienet and 7 patients to test the real-time implementation of MRSIGMA. Dice coefficients between real-time MRSIGMA and a retrospectively computed 4D reference were used to evaluate motion tracking performance. RESULTS: Motion dictionary was computed in under 5 s. Signature acquisition and matching presented 173 ms latency on the phantom and 193 ms on patients. MRSIGMA presented a mean error of 1.3-1.6 mm for all phantom experiments, which was below the 2 mm acquisition resolution along the motion direction. The Dice coefficient over time between MRSIGMA and reference contours was 0.88 ± 0.02 (GTV), 0.87 ± 0.02(duodenum-stomach), and 0.78 ± 0.02(small bowel), demonstrating high motion tracking performance for both tumor and organs at risk. CONCLUSION: The real-time implementation of MRSIGMA enabled true real-time free-breathing 3D MRI with sub-200 ms imaging latency on a clinical MR-Linac system, which can be used for treatment monitoring, adaptive radiotherapy and dose accumulation mapping in tumors affected by respiratory motion.

2.
Anal Chim Acta ; 1304: 342526, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38637046

RESUMO

The design and fabrication of high-performance electrode devices are highly important for the practical application of electrochemical sensors. In this study, flexible three-dimensional porous graphene electrode devices were first facilely fabricated using common laser ablation technique at room temperature. After then, hydrophilic two-dimensional MXene (Ti3C2Tx) nanosheet was decorated on the surface of the laser-induced graphene (LIG), resulting in disposable Ti3C2Tx/LIG electrode devices. After introducing Ti3C2Tx nanosheet, the electrochemical active area, electron transfer ability of LIG electrode device and its adsorption efficiency toward organic pesticide benomyl was significantly boosted. As a result, the fabricated Ti3C2Tx/LIG electrode device exhibited significantly enhanced electrocatalytic activity toward benomyl oxidation. Based on this, a novel and ultra-sensitive electrochemical platform for micro-droplet detection of benomyl was achieved in the range of 10 nM-6000 nM with detection sensitivity of 169.9 µA µM-1 cm-2 and detection limit of 5.8 nM. Considering the low-cost Ti3C2Tx/LIG electrode devices are rarely used for electrochemical analysis, we believed this research work will contribute to exploring the broader application of MXene/LIG electrode devices in the field of electrochemical sensing.

3.
J Environ Sci (China) ; 142: 248-258, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38527890

RESUMO

Brown carbon (BrC) is one of the important light absorption substances that have high light absorption ability under short wavelength light. However, limit studies have focused on the BrC emission from ships. In this study, size-segregated particulate matters (PM) were collected from three different types of ships, light absorption characteristics and size distribution of methanol-soluble BrC and water-soluble BrC in PM from ship exhausts were investigated. Results showed that four-stroke low-power diesel fishing boat (4-LDF) had the highest mass concentrations of methanol-soluble organic carbon (MSOC) and water-soluble organic carbon (WSOC), followed by 2-stroke high-power heavy-fuel-oil vessel (2-HHV), and four-stroke high-power marine-diesel vessel (4-HMV). While 2-HHV had obviously higher light absorption coefficients of methanol-soluble BrC (Abs365,M) and water-soluble BrC (Abs365,W) in unit weight of PM than the other two types of ships. The tested ships presented comparable or higher absorption efficiency of BrC in water extracts (MAE365,W) compared with other BrC emission sources. Majority of BrC was concentrated in fine particles, and the particle size distributions of both Abs365,M and Abs365,W showed bimodal patterns, peaking at 0.43-0.65 µm and 4.7-5.8 µm, respectively. However, different particle size distributions were found for MAE365,M between diesel and heavy fuel oil ships. Besides, different wavelength dependence in particles with different size were also detected. Ship exhaust could be confirmed as a non-ignorable BrC emission source, and complex influencing factor could affect the light absorption characteristics of ship emissions. Particle size should also be considered when light absorption ability of BrC was evaluated.


Assuntos
Poluentes Atmosféricos , Poluentes Atmosféricos/análise , Navios , Carbono/análise , Metanol , Monitoramento Ambiental/métodos , Aerossóis/análise , Material Particulado/análise , Emissões de Veículos , Água , China
4.
Nature ; 627(8003): 313-320, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38480964

RESUMO

Intrinsically stretchable electronics with skin-like mechanical properties have been identified as a promising platform for emerging applications ranging from continuous physiological monitoring to real-time analysis of health conditions, to closed-loop delivery of autonomous medical treatment1-7. However, current technologies could only reach electrical performance at amorphous-silicon level (that is, charge-carrier mobility of about 1 cm2 V-1 s-1), low integration scale (for example, 54 transistors per circuit) and limited functionalities8-11. Here we report high-density, intrinsically stretchable transistors and integrated circuits with high driving ability, high operation speed and large-scale integration. They were enabled by a combination of innovations in materials, fabrication process design, device engineering and circuit design. Our intrinsically stretchable transistors exhibit an average field-effect mobility of more than 20 cm2 V-1 s-1 under 100% strain, a device density of 100,000 transistors per cm2, including interconnects and a high drive current of around 2 µA µm-1 at a supply voltage of 5 V. Notably, these achieved parameters are on par with state-of-the-art flexible transistors based on metal-oxide, carbon nanotube and polycrystalline silicon materials on plastic substrates12-14. Furthermore, we realize a large-scale integrated circuit with more than 1,000 transistors and a stage-switching frequency greater than 1 MHz, for the first time, to our knowledge, in intrinsically stretchable electronics. Moreover, we demonstrate a high-throughput braille recognition system that surpasses human skin sensing ability, enabled by an active-matrix tactile sensor array with a record-high density of 2,500 units per cm2, and a light-emitting diode display with a high refreshing speed of 60 Hz and excellent mechanical robustness. The above advancements in device performance have substantially enhanced the abilities of skin-like electronics.


Assuntos
Desenho de Equipamento , Pele , Transistores Eletrônicos , Dispositivos Eletrônicos Vestíveis , Humanos , Silício , Nanotubos de Carbono , Tato
5.
J Cell Biochem ; 125(3): e30529, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38308620

RESUMO

Sept8 is a vesicle associated protein and there are two typical transcriptional variants (Sept8-204 and Sept8-201) expressed in mice brain. Interestingly, the coexpression of Sept8-204/Sept5 induces the formation of small sized vesicle-like structure, while that of the Sept8-201/Sept5 produces large puncta. Sept8 is previously shown to be palmitoylated. Here it was further revealed that protein palmitoylation is required for Sept8-204/Sept5 to maintain small sized vesicle-like structure and colocalize with synaptophysin, since either the expression of nonpalmitoylated Sept8-204 mutant (Sept8-204-3CA) or inhibiting Sept8-204 palmitoylation by 2-BP with Sept5 produces large puncta, which barely colocalizes with synaptophysin (SYP). Moreover, it was shown that the dynamic palmitoylation of Sept8-204 is controlled by ZDHHC17 and PPT1, loss of ZDHHC17 decreases Sept8-204 palmitoylation and induces large puncta, while loss of PPT1 increases Sept8-204 palmitoylation and induces small sized vesicle-like structure. Together, these findings suggest that palmitoylation is essential for the maintenance of the small sized vesicle-like structure for Sept8-204/Sept5, and may hint their important roles in synaptic functions.


Assuntos
Lipoilação , Septinas , Animais , Camundongos , Proteínas de Ciclo Celular/metabolismo , Septinas/genética , Septinas/metabolismo , Sinaptofisina/genética , Sinaptofisina/metabolismo
6.
Aging (Albany NY) ; 16(4): 3716-3733, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38364252

RESUMO

Accumulating evidence suggests that aberrant miRNAs participate in carcinogenesis and progression of hepatocellular carcinoma (HCC). Abnormal miR-557 expression is reported to interfere with the progression of several human cancers. However, the potential roles of miR-557 in HCC remain largely unknown. In the current study, we found that miR-557 was down-regulated in HCC tissues and cell lines, and was closely related to recurrence and metastasis of HCC. Notably, overexpression of miR-557 inhibited proliferation, migration, invasion, epithelial-to-mesenchymal transition (EMT) progression, blocked cells in G0/G1 phase of MHCC-97H cells in vitro, and suppressed tumor growth in vivo. However, loss of miR-557 facilitated these parameters in Huh7 cells both in vitro and in vivo. Moreover, RAB10 was identified as a direct downstream target of miR-557 through its 3'-UTR. Furthermore, RAB10 re-expression or knockdown partially abolished the effects of miR-557 on proliferation, migration, invasion, and EMT progression of HCC cells. Mechanistically, overexpression of miR-557 suppressed Wnt/ß-catenin signaling by inhibiting GSK-3ß phosphorylation, increasing ß-catenin phosphorylation, and decreasing ß-catenin transport to the nucleus, while knockdown of miR-557 activated Wnt/ß-catenin signaling. Moreover, the TOP/FOP-Flash reporter assays showed that miR-557 overexpression or knockdown significantly suppressed or activated Wnt signaling activity, respectively. Additionally, low expression of miR-557 and high expression of RAB10 in HCC tissues was closely associated with tumor size, degree of differentiation, TNM stage and poor prognosis in HCC patients. Taken together, these results demonstrate that miR-557 blocks the progression of HCC via the Wnt/ß-catenin pathway by targeting RAB10.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , MicroRNAs , Humanos , Carcinoma Hepatocelular/patologia , Via de Sinalização Wnt/genética , beta Catenina/genética , beta Catenina/metabolismo , Neoplasias Hepáticas/patologia , Glicogênio Sintase Quinase 3 beta/genética , Glicogênio Sintase Quinase 3 beta/metabolismo , Linhagem Celular Tumoral , MicroRNAs/genética , MicroRNAs/metabolismo , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Movimento Celular/genética
7.
Antonie Van Leeuwenhoek ; 117(1): 31, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38319408

RESUMO

An endophytic actinobacterium, designated strain HUAS 5T, was isolated from the root tissue of Cathaya argyrophylla collected in Chenzhou city of Hunan Province, PR China. This strain produced grey aerial mycelium that differentiated into spiral spore chains with spiny-surfaced ellipsoidal spores on Gause's synthetic No. 1 medium. Strain HUAS 5T grew well on Gause's synthetic No. 1, Reasoner'2 and ISP serial media. This strain grew at 15-40 °C (optimum, 28 °C), pH 6.0-9.0 (optimum, pH 7.0) and in presence of 0-5.0% (w/v) NaCl. The predominant cellular fatty acids of strain HUAS 5T (> 5.0%) were iso-C16:0, iso-C14:0, anteiso-C15:0, iso-C15:0, C16:0, iso-C16:1 H and Sum in Feature 3 (C16:1 ω7c/C16:1 ω6c). Sequence analysis of the 16S rRNA gene indicated that this strain belonged to the genus Streptomyces and exhibited highest sequence similarity to Streptomyces hirsutus NRRL B-2713T (97.3%), which is much less than 98.7% cut-off point of species definitions for bacteria and archaea. Phylogenetic analysis of 16S rRNA gene sequence and whole genome indicated that strain HUAS 5T formed an independent lineage, which suggested that it belonged to a potential novel species. Based on the morphological, cultural, physio-biochemical properties and chemotaxonomy, strain HUAS 5T (= MCCC 1K08552T = JCM 36055T) is deemed to represent a novel Streptomyces species, for which we put forward the name Streptomyces cathayae sp. nov.


Assuntos
Archaea , Streptomyces , Filogenia , RNA Ribossômico 16S/genética , China , Streptomyces/genética
8.
Environ Sci Technol ; 58(6): 2912-2921, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38252977

RESUMO

Currently, atmospheric sulfate aerosols cannot be predicted reliably by numerical models because the pathways and kinetics of sulfate formation are unclear. Here, we systematically investigated the synergetic catalyzing role of transition-metal ions (TMIs, Fe3+/Mn2+) in the oxidation of SO2 by O2 on aerosols using chamber experiments. Our results showed that the synergetic effect of TMIs is critically dependent on aerosol pH due to the solubility of Fe(III) species sensitive to the aqueous phase acidity, which is effective only under pH < 3 conditions. The sulfate formation rate on aerosols is 2 orders of magnitude larger than that in bulk solution and increases significantly on smaller aerosols, suggesting that such a synergetic-catalyzed oxidation occurs on the aerosol surface. The kinetic reaction rate can be described as R = k*[H+]-2.95[Mn(II)][Fe(III)][S(IV)] (pH ≤ 3.0). We found that TMI-synergetic-catalyzed oxidation is the dominant pathway of sulfate formation in Beijing when haze particles are very acidic, while heterogeneous oxidation of SO2 by NO2 is the most important pathway when haze particles are weakly acidic. Our work for the first time clarified the role and kinetics of TMI-synergetic-catalyzed oxidation of SO2 by O2 in haze periods, which can be parameterized into models for future studies of sulfate formation.


Assuntos
Poluentes Atmosféricos , Pequim , Sulfatos/análise , Compostos Férricos , Óxidos de Enxofre , Aerossóis , Catálise , Material Particulado , China
9.
Environ Pollut ; 341: 123016, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38008253

RESUMO

Mercury (Hg) and its inorganic and organic compounds significantly threaten the ecosystem and human health. However, the natural and anthropogenic Hg environmental inputs exceed 5000 metric tons annually. Hg is usually discharged in elemental or ionic forms, accumulating in surface water and sediments where Hg-methylating microbes-mediated biotransformation occurs. Microbial genetic factors such as the mer operon play a significant role in the complex Hg biogeochemical cycle. Previous reviews summarize the fate of environmental Hg, its biogeochemistry, and the mechanism of bacterial Hg resistance. This review mainly focuses on the mer operon and its components in detecting, absorbing, bioaccumulating, and detoxifying environmental Hg. Four components of the mer operon, including the MerR regulator, divergent mer promoter, and detoxification factors MerA and MerB, are rare bio-parts for assembling synthetic bacteria, which tackle pollutant Hg. Bacteria are designed to integrate synthetic biology, protein engineering, and metabolic engineering. In summary, this review highlights that designed bacteria based on the mer operon can potentially sense and bioremediate pollutant Hg in a green and low-cost manner.


Assuntos
Poluentes Ambientais , Mercúrio , Humanos , Mercúrio/metabolismo , Ecossistema , Bactérias/genética , Bactérias/metabolismo , Óperon , Poluentes Ambientais/metabolismo
10.
Magn Reson Med ; 91(2): 600-614, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37849064

RESUMO

PURPOSE: To develop a novel deep learning approach for 4D-MRI reconstruction, named Movienet, which exploits space-time-coil correlations and motion preservation instead of k-space data consistency, to accelerate the acquisition of golden-angle radial data and enable subsecond reconstruction times in dynamic MRI. METHODS: Movienet uses a U-net architecture with modified residual learning blocks that operate entirely in the image domain to remove aliasing artifacts and reconstruct an unaliased motion-resolved 4D image. Motion preservation is enforced by sorting the input image and reference for training in a linear motion order from expiration to inspiration. The input image was collected with a lower scan time than the reference XD-GRASP image used for training. Movienet is demonstrated for motion-resolved 4D MRI and motion-resistant 3D MRI of abdominal tumors on a therapeutic 1.5T MR-Linac (1.5-fold acquisition acceleration) and diagnostic 3T MRI scanners (2-fold and 2.25-fold acquisition acceleration for 4D and 3D, respectively). Image quality was evaluated quantitatively and qualitatively by expert clinical readers. RESULTS: The reconstruction time of Movienet was 0.69 s (4 motion states) and 0.75 s (10 motion states), which is substantially lower than iterative XD-GRASP and unrolled reconstruction networks. Movienet enables faster acquisition than XD-GRASP with similar overall image quality and improved suppression of streaking artifacts. CONCLUSION: Movienet accelerates data acquisition with respect to compressed sensing and reconstructs 4D images in less than 1 s, which would enable an efficient implementation of 4D MRI in a clinical setting for fast motion-resistant 3D anatomical imaging or motion-resolved 4D imaging.


Assuntos
Imageamento por Ressonância Magnética , Técnicas de Imagem de Sincronização Respiratória , Imageamento por Ressonância Magnética/métodos , Imageamento Tridimensional/métodos , Movimento (Física) , Aceleração , Técnicas de Imagem de Sincronização Respiratória/métodos , Processamento de Imagem Assistida por Computador/métodos , Respiração
11.
Sci Signal ; 16(814): eadi8645, 2023 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-38051778

RESUMO

Septin proteins are involved in diverse physiological functions, including the formation of specialized cytoskeletal structures. Septin 8 (Sept8) is implicated in spine morphogenesis and dendritic branching through palmitoylation. We explored the role and regulation of a Sept8 variant in human neural-like cells and in the mouse brain. We identified Sept8-204 as a brain-specific variant of Sept8 that was abundant in neurons and modified by palmitoylation, specifically at Cys469, Cys470, and Cys472. Sept8-204 palmitoylation was mediated by the palmitoyltransferase ZDHHC7 and was removed by the depalmitoylase PPT1. Palmitoylation of Sept8-204 bound to F-actin and induced cytoskeletal dynamics to promote the outgrowth of filopodia in N2a cells and the arborization of neurites in hippocampal neurons. In contrast, a Sept8-204 variant that could not be palmitoylated because of mutation of all three Cys residues (Sept8-204-3CA) lost its ability to bind F-actin, and expression of this mutant did not promote morphological changes. Genetic deletion of Sept8, Sept8-204, or Zdhhc7 caused deficits in learning and memory and promoted anxiety-like behaviors in mice. Our findings provide greater insight into the regulation of Sept8-204 by palmitoylation and its role in neuronal morphology and function in relation to cognition.


Assuntos
Actinas , Septinas , Camundongos , Humanos , Animais , Actinas/genética , Septinas/genética , Pseudópodes/genética , Neurônios/fisiologia , Ansiedade/genética
12.
ACS Appl Mater Interfaces ; 15(51): 59866-59875, 2023 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-38108287

RESUMO

Fiber-reinforced phenolic resin aerogel (FRPRA) composite materials are seductive candidates for high-temperature thermal protection owing to their low density, excellent thermostability, and thermal insulation. However, the intrinsic stiffness restricts their further application for high efficiency. We report a homogeneous and chemical bonding strategy for fabricating lightweight and flexible FRPRA with good ablative thermal insulation performance. The compressible (cyclic strain of 60%) and bendable (cyclic strain of 30%) abilities as well as the structural stability during ablation all benefit from the compatibility between the phenolic resin aerogel matrix and the phenolic fiber reinforcement. Additionally, low bulk density and thermal conductivity of 0.20 g cm-3 and 0.043 W m-1 K-1, respectively, endow the composite with efficient thermal insulation capability. With an 8 mm-thick coupon, the temperature of 200 °C can be decreased to 70.6 °C and the temperature around 1200 °C can be camouflaged to 78 °C through combining with the Al panel. The material also enables a conformal stealth of 600 °C based on its bendability. Hence, the composite has potential in applications of both static and dynamic thermal insulation.

13.
Theranostics ; 13(15): 5322-5347, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37908727

RESUMO

Cancer is still one of the major problems threatening human health and the therapeutical efficacies of available treatment choices are often rather low. Due to their favorable biocompatibility, simplicity of modification, and improved therapeutic efficacy, peptide-based self-assembled delivery systems have undergone significant evolution. Physical encapsulation and covalent conjugation are two common approaches to load drugs for peptide assembly-based delivery, which are always associated with drug leaks in the blood circulation system or changed pharmacological activities, respectively. To overcome these difficulties, a more elegant peptide-based assembly strategy is desired. Notably, peptide-mediated co-assembly with drug molecules provides a new method for constructing nanomaterials with improved versatility and structural stability. The co-assembly strategy can be used to design various nanostructures for cancer therapy, such as nanotubes, nanofibrils, hydrogels, and nanovesicles. Recently, these co-assembled nanostructures have gained tremendous attention for their unique superiorities in tumor therapy. This article describes the classification of assembled peptides, driving forces for co-assembly, and specifically, the design methodologies for various drug molecules in co-assembly. It also highlights recent research on peptide-mediated co-assembled delivery systems for cancer therapy. Finally, it summarizes the pros and cons of co-assembly in cancer therapy and offers some suggestions for conquering the challenges in this field.


Assuntos
Nanoestruturas , Nanotubos , Neoplasias , Humanos , Peptídeos/química , Nanoestruturas/química , Hidrogéis/química , Neoplasias/tratamento farmacológico , Sistemas de Liberação de Medicamentos/métodos
14.
BMC Surg ; 23(1): 336, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37940918

RESUMO

BACKGROUND: With the development of minimally invasive technology, the trauma caused by surgery get smaller, At the same time, the specimen extraction surgery through the natural orifice is more favored by experts domestically and abroad, robotic surgery has further promoted the development of specimen extraction surgery through the natural orifice. The aim of current study is to compare the short-term outcomes of robotic-assisted natural orifice specimen extraction (NOSES ) and transabdominal specimen extraction(TRSE ) in median rectal cancer surgery. METHODS: From January 2020 to January 2023, 87 patients who underwent the NOSES or TRSE at the First Affiliated Hospital of Nanchang University were included in the study, 4 patients were excluded due to liver metastasis. Of these, 50 patients were in the TRSE and 33 patients in the NOSES. Short-term efficacy was compared in the two groups. RESULTS: The NOSES group had less operation time (P < 0.001), faster recovery of gastrointestinal function (P < 0.001), shorter abdominal incisions (P < 0.001), lower pain scores(P < 0.001). lower Inflammatory indicators of the white blood cell count and C-reactive protein content at 1, 3, and 5 days after surgery (P < 0.001, P = 0.037). There were 9 complications in the NOSES group and 11 complications in the TRSE group(P = 0.583). However, there were no wound complications in the NOSES group. The number of postoperative hospital stays seems to be same in the two groups. And there was no significant difference in postoperative anus function (P = 0.591). CONCLUSIONS: This study shows that NOSES and TRSE can achieve similar radical treatment effects, NOSES is a feasible and safe way to take specimens for rectal cancer surgery in accordance with the indication for NOSES.


Assuntos
Laparoscopia , Neoplasias Retais , Procedimentos Cirúrgicos Robóticos , Humanos , Estudos Retrospectivos , Neoplasias Retais/cirurgia , Reto , Resultado do Tratamento
15.
bioRxiv ; 2023 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-37873341

RESUMO

Bioelectronic fibers hold promise for both research and clinical applications due to their compactness, ease of implantation, and ability to incorporate various functionalities such as sensing and stimulation. However, existing devices suffer from bulkiness, rigidity, limited functionality, and low density of active components. These limitations stem from the difficulty to incorporate many components on one-dimensional (1D) fiber devices due to the incompatibility of conventional microfabrication methods (e.g., photolithography) with curved, thin and long fiber structures. Herein, we introduce a fabrication approach, ‶spiral transformation″, to convert two-dimensional (2D) films containing microfabricated devices into 1D soft fibers. This approach allows for the creation of high density multimodal soft bioelectronic fibers, termed Spiral NeuroString (S-NeuroString), while enabling precise control over the longitudinal, angular, and radial positioning and distribution of the functional components. We show the utility of S-NeuroString for motility mapping, serotonin sensing, and tissue stimulation within the dynamic and soft gastrointestinal (GI) system, as well as for single-unit recordings in the brain. The described bioelectronic fibers hold great promises for next-generation multifunctional implantable electronics.

16.
Environ Sci Technol ; 57(42): 15979-15989, 2023 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-37821356

RESUMO

Aerosol nitrate (NO3-) constitutes a significant component of fine particles in China. Prioritizing the control of volatile organic compounds (VOCs) is a crucial step toward achieving clean air, yet its impact on NO3- pollution remains inadequately understood. Here, we examined the role of VOCs in NO3- formation by combining comprehensive field measurements conducted during the China International Import Expo (CIIE) in Shanghai (from 10 October to 22 November 2018) and multiphase chemical modeling. Despite a decline in primary pollutants during the CIIE, NO3- levels increased compared to pre-CIIE and post-CIIE─NO3- concentrations decreased in the daytime (by -10 and -26%) while increasing in the nighttime (by 8 and 30%). Analysis of the observations and backward trajectory indicates that the diurnal variation in NO3- was mainly attributed to local chemistry rather than meteorological conditions. Decreasing VOCs lowered the daytime NO3- production by reducing the hydroxyl radical level, whereas the greater VOCs reduction at night than that in the daytime increased the nitrate radical level, thereby promoting the nocturnal NO3- production. These results reveal the double-edged role of VOCs in NO3- formation, underscoring the need for transferring large VOC-emitting enterprises from the daytime to the nighttime, which should be considered in formulating corresponding policies.


Assuntos
Poluentes Atmosféricos , Ozônio , Compostos Orgânicos Voláteis , Nitratos/análise , Compostos Orgânicos Voláteis/análise , Poluentes Atmosféricos/análise , China , Poluição Ambiental/análise , Monitoramento Ambiental , Ozônio/análise
17.
Anal Chim Acta ; 1279: 341772, 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37827671

RESUMO

Using planar π-conjugated 2,5-diamino-1,4-benzenedithiol as organic ligand, Co-based conjugated coordination polymers (CoCCPs) with different morphology were prepared through controlling the injection rate of Co2+. When the injection rate decreases from 1.00 to 0.25 mL min-1, the obtained CoCCPs change from 2D nanosheets to quasi-1D nanorods. It is found that the different-shaped CoCCPs exhibit varying electrochemical sensing performance. The prepared CoCCPs-1 with quasi-1D nanowires and porous network structure possesses larger active area, faster electron transfer and higher accumulation ability. Moreover, the CoCCPs-1 is more active for the oxidation of p-nitrophenol (PNP), and greatly enhances its oxidation signal. Based on the morphology-tuned sensing performance of CoCCPs, a highly-sensitive electrochemical sensor has been developed for PNP, with detection limit of 0.00986 µM (9.86 nM). It was used in the analysis of wastewater samples, and the results is validated by other instrumental method.

18.
Antonie Van Leeuwenhoek ; 116(12): 1277-1284, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37749324

RESUMO

Strain HUAS 13-4T, a novel endophytic actinobacterium, was isolated from the leaves of Cynara scolymus L. collected from Changde City in China and characterized using a polyphasic approach. Based on 16S rRNA gene sequence analysis, strain HUAS 13-4T shared the highest sequence similarities to Streptomyces leeuwenhoekii C34T (98.90%), Streptomyces harenosi PRKS01-65T (98.83%) and Streptomyces glomeratus LMG 19903T (98.76%). Phylogenetic analysis of 16S rRNA gene sequence indicated that strain HUAS 13-4T was clustered together with Streptomyces bluensis ISP 5564T and Streptomyces cavernae SYSU K10008T. Phylogenomic analysis revealed that strain HUAS 13-4T was most closely related to S. glomeratus JCM 9091T. However, the average nucleotide identity and the digital DNA-DNA hybridization values between them were less than 96.7% and 70% cut-off points recommended for delineating species. Based on a comprehensive comparison of the genome sequences and phenotypic characteristics between strain HUAS 13-4T and its relative, strain HUAS 13-4T (= MCCC 1K08364T = JCM 35919T) should evidently represent a novel Streptomyces species, and the name Streptomyces cynarae sp. nov. is proposed.


Assuntos
Actinobacteria , Cynara scolymus , Streptomyces , Ácidos Graxos , Fosfolipídeos , Cynara scolymus/genética , Análise de Sequência de DNA , Filogenia , RNA Ribossômico 16S/genética , Actinobacteria/genética , Composição de Bases , DNA , DNA Bacteriano/genética , Técnicas de Tipagem Bacteriana
19.
Phys Med Biol ; 68(18)2023 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-37619588

RESUMO

Objective. To develop real-time 4D MRI using MR signature matching (MRSIGMA) for volumetric motion imaging in patients with pancreatic cancer on a 1.5T MR-Linac system.Approach. Two consecutive MRI scans with 3D golden-angle radial stack-of-stars acquisitions were performed on ten patients with inoperable pancreatic cancer. The complete first scan (905 angles) was used to compute a 4D motion dictionary including ten pairs of 3D motion images and signatures. The second scan was used for real-time imaging, where each angle (275 ms) was processed separately to match it to one of the dictionary entries. The complete second scan was also used to compute a 4D reference to assess motion tracking performance.Dicecoefficients of the gross tumor volume (GTV) and two organs-at-risk (duodenum-stomach and small bowel) were calculated between signature matching and reference. In addition, volume changes, displacements, center of mass shifts, andDicescores over time were calculated to characterize motion.Main results. Total imaging latency of MRSIGMA (acquisition + matching) was less than 300 ms. TheDicecoefficients were 0.87 ± 0.06 (GTV), 0.86 ± 0.05 (duodenum-stomach), and 0.85 ± 0.05 (small bowel), which indicate high accuracy (high mean value) and low uncertainty (low standard deviation) of MRSIGMA for real-time motion tracking. The center of mass shift was 3.1 ± 2.0 mm (GTV), 5.3 ± 3.0 mm (duodenum-stomach), and 3.4 ± 1.5 mm (small bowel). TheDicescores over time (0.97 ± [0.01-0.03]) were similarly high for MRSIGMA and reference scans in all the three contours.Significance. This work demonstrates the feasibility of real-time 4D MRI using MRSIGMA for volumetric motion tracking on a 1.5T MR-Linac system. The high accuracy and low uncertainty of real-time MRSIGMA is an essential step towards continuous treatment adaptation of tumors affected by real-time respiratory motion and could ultimately improve treatment safety by optimizing ablative dose delivery near gastrointestinal organs.


Assuntos
Imageamento por Ressonância Magnética , Neoplasias Pancreáticas , Humanos , Neoplasias Pancreáticas/diagnóstico por imagem , Movimento (Física) , Órgãos em Risco , Neoplasias Pancreáticas
20.
Anal Chim Acta ; 1277: 341675, 2023 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-37604626

RESUMO

Construction of novel two-dimensional porous carbon nanosheets with superior electrochemical activity is of great challenge. Here, graphene/ZIF-8 nano-sandwiches derived N, P-codoped porous carbon nanosheets (N, P-codoped PCN) was easily obtained by sequential room temperature self-assembly and high-temperature carbonization method. Relative to the widely used physically exfoliated graphene nanosheets (GN) and graphene/ZIF-8 derived N-doped porous carbon nanosheets (N-doped PCN), N, P-codoped PCN displayed larger active surface, faster electron transport ability and stronger physical adsorption ability, which can be ascribed to the dual doping effect of heteroatoms N and P. As a result, N, P-codoped PCN exhibited remarkable oxidation signal enhancement for tumor marker (8-hydroxy-2'-deoxyguanosine), analgesic and antipyretic drug (acetaminophen) and organic pesticide (benomyl). Besides, the limits of detection were measured as low as 1.58 nM, 7.50 nM and 2.10 nM with sensitivity of 270.00 µA µM-1 cm-2, 757.14 µA µM-1 cm-2 and 272.86 µA µM-1 cm-2 for 8-hydroxy-2'-deoxyguanosine, acetaminophen and benomyl, respectively. Basing on this, a novel and highly sensitive electrochemical sensing platform was developed. It is believed that the reported two-dimensional N, P-codoped PCN with unique structure and composition is highly valuable for the development of carbon-based electrochemical sensors.

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