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Converting fatty acids into specialty chemicals is sustainable but hindered by the low efficiency and thermal instability of current oleic acid hydratases, along with mass transfer limitations in emulsion reactions. This study introduces an optimized continuous flow micro-reactor (CFMR) that efficiently transforms oleic acid at low (15 g·L-1) and high (50 g·L-1) concentrations, improving reaction efficiency and overcoming key conversion barriers. The first CFMR model showed reaction speeds surpassing traditional batch stirred tank reactors (BSTR). Optimizations were performed on three key components: liquid storage, mixer, and reaction section of the CFMR, with each round's best conditions carried into the next. This achieved a space-time yield of 597 g·L-1·d-1 at a 15 g·L-1 oleic acid load. To further enhance the yield, we optimized the emulsifier system to solve incomplete emulsification and developed a two-component feed microreactor (TCFMR) that addressed substrate and product inhibition at high loads, reaching a 91% conversion of 50 g·L-1 oleic acid in 30 minutes, with a space-time yield of 2312 g·L-1·d-1. These advancements represent significant progress in utilizing fatty acids and advancing sustainable chemical synthesis.
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OBJECTIVE: The current guidelines and canonical norms of diagnosis or treatment for Post-traumatic stress disorder (PTSD) with sleep disorder are still conflicting and have not yet reached a consensus. This study aimed to unravel the most effective countermeasures between two categories (psychotherapy and pharmacotherapy) put forward by the National Institute for Health and Clinical Excellence (NICE) and World Federation of Societies of Biological Psychiatry (WFSBP) respectively to treat PTSD individuals co-exist with sleep disorders. METHODS: Four databases, including PubMed, EMBASE, Cochrane Library, and APA PsyNet, were searched from inception to February 02, 2023. RESULTS: Twenty articles with 24 Randomized controlled trials (RCTs) and a total number of 1,647 participants were included. As demonstrated in the network meta-analysis comparison results, CBT-I (standardized mean differences (SMD) = -1.51,95% confidence interval (CI):-2.55 to -0.47), CBT-I plus IRT (SMD = -1.71, 95%CI:-3.39, -0.03), prazosin (SMD = -0.87,95%CI:-1.59 to -0.16) and hydroxyzine (SMD = -1.06, 95%CI: -1.94 to -0.19) significantly reduced PTSD symptoms compared with placebo. In contrast to placebo, CBT-I (SMD = -5.61,95%CI:-8.82 to -2.40) significantly improved sleep quality. For nightmare severity, IRT (SMD =-0.65, 95%CI:-1.00 to -0.31), prazosin (SMD = -1.20,95%CI:-1.72 to -0.67) and hydroxyzine (SMD = -0.98,95%CI:-1.58 to -0.37) significantly reduced nightmare severity in comparison with placebo. CONCLUSIONS: This study suggested that under most circumstances, psychotherapy namely CBT-I had a favorable profile, but pharmacotherapy with prazosin was effective in managing nightmare severity. The sole avail of CBT-I was recommended to improving sleep quality while CBT-I and CBT-I plus IRT showed excellent management of PTSD symptom severity. Exposure to CBT-I isrecommended for depression. The relevant clinical guidelines for the management of individuals with PTSD and sleep disorders may regard this as a reference. PROSPERO: CRD42023415240.
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Metanálise em Rede , Prazosina , Ensaios Clínicos Controlados Aleatórios como Assunto , Transtornos do Sono-Vigília , Transtornos de Estresse Pós-Traumáticos , Humanos , Transtornos de Estresse Pós-Traumáticos/tratamento farmacológico , Transtornos de Estresse Pós-Traumáticos/terapia , Prazosina/uso terapêutico , Transtornos do Sono-Vigília/tratamento farmacológico , Transtornos do Sono-Vigília/terapia , Terapia Cognitivo-Comportamental/métodos , Psicoterapia/métodos , Resultado do Tratamento , Masculino , Feminino , Adulto , Dessensibilização e Reprocessamento através dos Movimentos Oculares/métodos , Hidroxizina/uso terapêuticoRESUMO
The interface of two materials can harbor unexpected emergent phenomena. One example is interface-induced superconductivity. In this work, we employ molecular beam epitaxy to grow a series of heterostructures formed by stacking together two nonsuperconducting antiferromagnetic materials, an intrinsic antiferromagnetic topological insulator MnBi2Te4 and an antiferromagnetic iron chalcogenide FeTe. Our electrical transport measurements reveal interface-induced superconductivity in these heterostructures. By performing scanning tunneling microscopy and spectroscopy measurements, we observe a proximity-induced superconducting gap on the top surface of the MnBi2Te4 layer, confirming the coexistence of superconductivity and antiferromagnetism in the MnBi2Te4 layer. Our findings will advance the fundamental inquiries into the topological superconducting phase in hybrid devices and provide a promising platform for the exploration of chiral Majorana physics in MnBi2Te4-based heterostructures.
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The plateau phase transition in quantum anomalous Hall (QAH) insulators corresponds to a quantum state wherein a single magnetic domain gives way to multiple domains and then reconverges back to a single magnetic domain. The layer structure of the sample provides an external knob for adjusting the Chern number C of the QAH insulators. Here, we employ molecular beam epitaxy to grow magnetic topological insulator multilayers and realize the magnetic field-driven plateau phase transition between two QAH states with odd Chern number change ΔC. We find that critical exponents extracted for the plateau phase transitions with ΔC = 1 and ΔC = 3 in QAH insulators are nearly identical. We construct a four-layer Chalker-Coddington network model to understand the consistent critical exponents for the plateau phase transitions with ΔC = 1 and ΔC = 3. This work will motivate further investigations into the critical behaviors of plateau phase transitions with different ΔC in QAH insulators.
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Current approaches to treating inflammatory bowel disease focus on the suppression of overactive immune responses, the removal of reactive intestinal oxygen species, and regulation of the intestinal flora. However, owing to the complex structure of the gastrointestinal tract and the influence of mucus, current small-molecule and biologic-based drugs for treating colitis cannot effectively act at the site of colon inflammation, and as a result, they tend to exhibit low efficacies and toxic side effects. In this study, nanogel-based multistage NO delivery microcapsules are developed to achieve NO release at the inflammation site by targeting the inflammatory tissues using the nanogel. Surprisingly, oral administration of the microcapsules suppresses the growth of pathogenic bacteria and increases the abundance of probiotic bacteria. Metabolomics further show that an increased abundance of intestinal probiotics promotes the production of metabolites, including short-chain fatty acids and indole derivatives, which modulate the intestinal immunity and restore the intestinal barrier via the interleukin-17 and PI3K-Akt signaling pathways. This work reveals that the developed gas therapy strategy based on multistage NO delivery microcapsules modulates the intestinal microbial balance, thereby reducing inflammation and promoting intestinal barrier repair, ultimately providing a new therapeutic approach for the clinical management of colitis.
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Cápsulas , Colite , Microbioma Gastrointestinal , Nanogéis , Óxido Nítrico , Colite/tratamento farmacológico , Animais , Cápsulas/química , Camundongos , Nanogéis/química , Óxido Nítrico/metabolismo , Probióticos , Polietilenoimina/química , Gases/química , Camundongos Endogâmicos C57BL , PolietilenoglicóisRESUMO
OBJECTIVE: To explore the feasibility of using marking and fusion image-guided technique with cone-beam CT (CBCT) in cases of kidney ruptured haemorrhage without extravascular leakage in digital subtraction angiography (DSA) images. METHODS: This is a retrospective case-control study that included 43 patients who underwent transcatheter arterial embolization for kidney ruptured haemorrhage and difficult haemostasis. The patients were divided into two groups: the CBCT group (cases without extravascular leakage observed in angiography) and the control group (cases with clearly identifiable target vessels in angiography). The baseline characteristics and clinical outcomes were collected and analysed. RESULTS: The results showed no statistically significant differences in the duration of the procedure and intraoperative blood transfusion between the control and CBCT groups (P > .05). The study clarified that the CBCT group had a significantly higher rate of improvement of gross haematuria compared to the control group (P < .05). The CBCT group showed a greater increase in haemoglobin and a lesser increase in creatinine. The clinical success rates were 87.5% in the control group and 90.9% in the CBCT group (P > .05). CONCLUSIONS: The marking and fusion image-guided technique is useful in cases of kidney ruptured haemorrhage without extravascular leakage of contrast agent. The technique is safe, feasible, and effective, and we believe it is superior to purely DSA-guidance. ADVANCES IN KNOWLEDGE: The use of the marking and fusion image-guided technique is recommended to overcome the challenge of undetectable target vessels during interventional procedures. This technique is considered as non-inferior to purely DSA-guided interventional procedures where the target vessels are clearly identifiable.
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Hemorragia , Rim , Humanos , Projetos Piloto , Estudos Retrospectivos , Estudos de Casos e Controles , Angiografia Digital/métodos , Hemorragia/diagnóstico por imagem , Tomografia Computadorizada de Feixe Cônico/métodosRESUMO
Silkworm pupae, by-product of sericulture industry, is massively discarded. The degradation rate of silkworm pupae protein is critical to further employment, which reduces the impact of waste on the environment. Herein, magnetic Janus mesoporous silica nanoparticles immobilized proteinase K mutant T206M and Mucor circinelloides aspartic protease were employed in the co-degradation. The thermostability of T206M improved by enhancing structural rigidity (t1/2 by 30 min and T50 by 5 °C), prompting the degradation efficiency. At 65 °C and pH 7, degradation rate reached the highest of 61.7%, which improved by 26% compared with single free protease degradation. Besides, the immobilized protease is easy to separate and reuse, which maintains 50% activity after 10 recycles. Therefore, immobilized protease co-degradation was first applied to the development and utilization of silkworm pupae resulting in the release of promising antioxidant properties and reduces the environmental impact by utilizing a natural and renewable resource.
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Bombyx , Endopeptidase K , Nanopartículas de Magnetita , Mucor , Pupa , Bombyx/metabolismo , Animais , Mucor/enzimologia , Nanopartículas de Magnetita/química , Endopeptidase K/metabolismo , Enzimas Imobilizadas/metabolismo , Enzimas Imobilizadas/química , Ácido Aspártico Proteases/metabolismo , Ácido Aspártico Proteases/química , Proteínas de Insetos/metabolismo , Proteínas de Insetos/químicaRESUMO
The interface between two different materials can show unexpected quantum phenomena. In this study, we used molecular beam epitaxy to synthesize heterostructures formed by stacking together two magnetic materials, a ferromagnetic topological insulator (TI) and an antiferromagnetic iron chalcogenide (FeTe). We observed emergent interface-induced superconductivity in these heterostructures and demonstrated the co-occurrence of superconductivity, ferromagnetism, and topological band structure in the magnetic TI layer-the three essential ingredients of chiral topological superconductivity (TSC). The unusual coexistence of ferromagnetism and superconductivity is accompanied by a high upper critical magnetic field that exceeds the Pauli paramagnetic limit for conventional superconductors at low temperatures. These magnetic TI/FeTe heterostructures with robust superconductivity and atomically sharp interfaces provide an ideal wafer-scale platform for the exploration of chiral TSC and Majorana physics.
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We propose an intrinsic mechanism to understand the even-odd effect, namely, opposite signs of anomalous Hall resistance and different shapes of hysteresis loops for even and odd septuple layers (SLs), of MBE-grown MnBi_{2}Te_{4} thin films with electron doping. The nonzero hysteresis loops in the anomalous Hall effect and magnetic circular dichroism for even-SLs MnBi_{2}Te_{4} films originate from two different antiferromagnetic (AFM) configurations with different zeroth Landau level energies of surface states. The complex form of the anomalous Hall hysteresis loop can be understood from two magnetic transitions, a transition between two AFM states followed by a second transition to the ferromagnetic state. Our model also clarifies the relationship and distinction between axion parameter and magnetoelectric coefficient, and shows an even-odd oscillation behavior of magnetoelectric coefficients in MnBi_{2}Te_{4} films.
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A quantum anomalous Hall (QAH) insulator is a topological phase in which the interior is insulating but electrical current flows along the edges of the sample in either a clockwise or counterclockwise direction, as dictated by the spontaneous magnetization orientation. Such a chiral edge current eliminates any backscattering, giving rise to quantized Hall resistance and zero longitudinal resistance. Here we fabricate mesoscopic QAH sandwich Hall bar devices and succeed in switching the edge current chirality through thermally assisted spin-orbit torque (SOT). The well-quantized QAH states before and after SOT switching with opposite edge current chiralities are demonstrated through four- and three-terminal measurements. We show that the SOT responsible for magnetization switching can be generated by both surface and bulk carriers. Our results further our understanding of the interplay between magnetism and topological states and usher in an easy and instantaneous method to manipulate the QAH state.
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Magnetic topological states refer to a class of exotic phases in magnetic materials with the non-trivial topological property determined by magnetic spin configurations. An example of such states is the quantum anomalous Hall (QAH) state, which is a zero magnetic field manifestation of the quantum Hall effect. Current research in this direction focuses on QAH insulators with a thickness of less than 10 nm. Here, molecular beam epitaxy (MBE) is employed to synthesize magnetic TI trilayers with a thickness of up to ≈106 nm. It is found that these samples exhibit well-quantized Hall resistance and vanishing longitudinal resistance at zero magnetic field. By varying the magnetic dopants, gate voltages, temperature, and external magnetic fields, the properties of these thick QAH insulators are examined and the robustness of the 3D QAH effect is demonstrated. The realization of the well-quantized 3D QAH effect indicates that the nonchiral side surface states of the thick magnetic TI trilayers are gapped and thus do not affect the QAH quantization. The 3D QAH insulators of hundred-nanometer thickness provide a promising platform for the exploration of fundamental physics, including axion physics and image magnetic monopole, and the advancement of electronic and spintronic devices to circumvent Moore's law.
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Electrical stimulation (ES) is proposed as a therapeutic solution for managing chronic wounds. However, its widespread clinical adoption is limited by the requirement of additional extracorporeal devices to power ES-based wound dressings. In this study, a novel sandwich-structured photovoltaic microcurrent hydrogel dressing (PMH dressing) is designed for treating diabetic wounds. This innovative dressing comprises flexible organic photovoltaic (OPV) cells, a flexible micro-electro-mechanical systems (MEMS) electrode, and a multifunctional hydrogel serving as an electrode-tissue interface. The PMH dressing is engineered to administer ES, mimicking the physiological injury current occurring naturally in wounds when exposed to light; thus, facilitating wound healing. In vitro experiments are performed to validate the PMH dressing's exceptional biocompatibility and robust antibacterial properties. In vivo experiments and proteomic analysis reveal that the proposed PMH dressing significantly accelerates the healing of infected diabetic wounds by enhancing extracellular matrix regeneration, eliminating bacteria, regulating inflammatory responses, and modulating vascular functions. Therefore, the PMH dressing is a potent, versatile, and effective solution for diabetic wound care, paving the way for advancements in wireless ES wound dressings.
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Diabetes Mellitus , Hidrogéis , Humanos , Biomimética , Proteômica , Cicatrização , BandagensRESUMO
Over the last decade, the possibility of realizing topological superconductivity (TSC) has generated much excitement. TSC can be created in electronic systems where the topological and superconducting orders coexist, motivating the continued exploration of candidate material platforms to this end. Here, we use molecular beam epitaxy (MBE) to synthesize heterostructures that host emergent interfacial superconductivity when a non-superconducting antiferromagnet (FeTe) is interfaced with a topological insulator (TI) (Bi, Sb)2Te3. By performing in-vacuo angle-resolved photoemission spectroscopy (ARPES) and ex-situ electrical transport measurements, we find that the superconducting transition temperature and the upper critical magnetic field are suppressed when the chemical potential approaches the Dirac point. We provide evidence to show that the observed interfacial superconductivity and its chemical potential dependence is the result of the competition between the Ruderman-Kittel-Kasuya-Yosida-type ferromagnetic coupling mediated by Dirac surface states and antiferromagnetic exchange couplings that generate the bicollinear antiferromagnetic order in the FeTe layer.
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An axion insulator is a three-dimensional (3D) topological insulator (TI), in which the bulk maintains the time-reversal symmetry or inversion symmetry but the surface states are gapped by surface magnetization. The axion insulator state has been observed in molecular beam epitaxy (MBE)-grown magnetically doped TI sandwiches and exfoliated intrinsic magnetic TI MnBi2Te4 flakes with an even number layer. All these samples have a thickness of ~ 10 nm, near the 2D-to-3D boundary. The coupling between the top and bottom surface states in thin samples may hinder the observation of quantized topological magnetoelectric response. Here, we employ MBE to synthesize magnetic TI sandwich heterostructures and find that the axion insulator state persists in a 3D sample with a thickness of ~ 106 nm. Our transport results show that the axion insulator state starts to emerge when the thickness of the middle undoped TI layer is greater than ~ 3 nm. The 3D hundred-nanometer-thick axion insulator provides a promising platform for the exploration of the topological magnetoelectric effect and other emergent magnetic topological states, such as the high-order TI phase.
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IMPORTANCE: Although Micropterus salmoides rhabdovirus (MSRV) causes serious fish epidemics worldwide, the detailed mechanism of MSRV entry into host cells remains unknown. Here, we comprehensively investigated the mechanism of MSRV entry into epithelioma papulosum cyprinid (EPC) cells. This study demonstrated that MSRV enters EPC cells via a low pH, dynamin-dependent, microtubule-dependent, and clathrin-mediated endocytosis. Subsequently, MSRV transports from early endosomes to late endosomes and further into lysosomes in a microtubule-dependent manner. The characterization of MSRV entry will further advance the understanding of rhabdovirus cellular entry pathways and provide novel targets for antiviral drug against MSRV infection.
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Bass , Rhabdoviridae , Animais , Rhabdoviridae/metabolismo , Bass/metabolismo , Proteínas rab5 de Ligação ao GTP/metabolismo , Endocitose , Dinaminas/metabolismo , Microtúbulos/metabolismo , Clatrina/metabolismo , Concentração de Íons de Hidrogênio , Internalização do VírusRESUMO
Microbial transformation is an efficient enzymatic approach for the structural modification of exogenous compounds to obtain derivatives. Compared with traditional chemical synthesis, the microbial transformation has in fact the undoubtable advantages of strong region-and stereo-selectivity, and a low environmental and economic impact on the production process, which can achieve the reactions challenging to chemical synthesis. Because microbes are equipped with a broad-spectrum of enzymes and therefore can metabolize various substrates, they are not only a significant route for obtaining novel active derivatives, but also an effective tool for mimicking mammal metabolism in vitro. Artemisinin, a sesquiterpene with a peroxy-bridged structure serving as the main active functional group, is a famous antimalarial agent discovered from Artemisia annua L. Some sesquiterpenoids, such as dihydroartemisinin, artemether, and arteether, have been developed on the basis of artemisinin, which have been successfully marketed and become the first-line antimalarial drugs recommended by WHO. As revealed by pharmacological studies, artemisinin and its derivatives have exhibited extensive biological activities, including antimalarial, antitumor, antiviral, anti-inflammatory, and immunomodulatory. As an efficient approach for structural modification, microbial transformation of artemisinin and its derivatives is an increasingly popular strategy that attracts considerable attention recently, and numerous novel derivatives have been discovered. Herein, this paper reviewed the microbial transformation of artemisinin and its artemisinin, including microbial strains, culture conditions, product isolation and yield, and biological activities, and summarized the advances in microbial transformation in obtaining active derivatives of artemisinin and the simulation of in vivo metabolism of drugs.
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Antimaláricos , Artemisininas , Animais , Antimaláricos/farmacologia , Antivirais , Artemeter , MamíferosRESUMO
OBJECTIVE: To assess whether prophylactic intraoperative abdominal aortic balloon occlusion (IAABO) is indeed beneficial in pregnancies with placenta previa (PP) and placenta accreta spectrum (PAS) during cesarean section. METHODS: A retrospective case-control study included 251 pregnancies with PP and/or PAS. All enrolled patients were divided into a PP/PAS group, a PP + PAS group, and an IAABO group. The demographic characteristics and maternal and neonatal outcomes were compared. RESULTS: There was no significant difference in blood loss and transfusion between the IAABO group and the PP + PAS group (P > 0.05). However, blood loss and red blood cell and fresh frozen plasma transfusion in the above two groups were significantly higher than in the PP/PAS group (P < 0.05). More pregnancies in the IAABO group had to undergo uterine artery embolization (29.2%) or hysterectomy (20.8%), and this percentage was significantly higher than that in the other two groups (P < 0.001). All neonatal characteristics did not show differences between the IAABO group and PP + PAS group (P > 0.05). IAABO led to femoral artery thrombosis in three cases and minor postoperative renal injury in one case. CONCLUSION: IAABO only acted as a less important supporting technique during cesarean section. There was no evidence suggesting that IAABO could significantly control the massive hemorrhage in pregnancies with PP and PAS during cesarean delivery.
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Oclusão com Balão , Cesárea , Placenta Acreta , Placenta Prévia , Feminino , Humanos , Recém-Nascido , Gravidez , Oclusão com Balão/métodos , Transfusão de Componentes Sanguíneos , Perda Sanguínea Cirúrgica/prevenção & controle , Estudos de Casos e Controles , Cesárea/efeitos adversos , Cesárea/métodos , Histerectomia , Placenta Acreta/cirurgia , Placenta Prévia/cirurgia , Plasma , Estudos RetrospectivosRESUMO
AIM: To explore the current situation and problems of interventional radiology (IR) staff, imaging equipment and procedures in hospitals. METHODS: An electronic questionnaire was sent to 186 officially registered secondary and tertiary hospitals through a dedicated network for medical administration in a city in China. Data collection efforts ceased two weeks after the questionnaire was sent out. RESULTS: The response rate was 100%. IR procedures were provided in 22 hospitals (11.8%). 50.0% were 2A level hospitals. 95.5% began to perform IR procedures in the last three decades. The IR workload of 3A level hospitals was significantly heavier than that in 3B or 2 level hospitals (1139.20±699.32 vs. 95.60±45.48, 1139.20±699.32 vs. 85.17±61.15; P<0.001). There were more senior interventional radiologists than juniors (43 vs. 41), and insufficient radiographers (radiographer-equipment ratio 0.91 ± 0.54). Thirteen hospitals (59.1%) had set up independent IR departments, and several clinical departments provided IR service at the same time in ten hospitals. CONCLUSIONS: The IR specialty of 3A hospitals had obvious advantages in staff, imaging equipment, and procedure volume over other hospitals. It should be noted that there were fewer junior interventional radiologists and the number of radiographers was inadequate. Further attract the talents to the IR field is important in future. KEY WORDS: Interventional radiology, Imaging equipment, Survey, Staff, Workload.
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Hospitais , Radiologia Intervencionista , Humanos , Radiologia Intervencionista/métodos , Inquéritos e Questionários , Carga de TrabalhoRESUMO
BACKGROUND: Ultrasound (US)-guided-only insertion at the bedside is safe and improves the success rates of peripherally inserted central catheter (PICC). However, PICC insertion procedures remain challenging for special cases. PURPOSE: To show that fluoroscopically guided tip repositioning, for failed US-guided PICC placement, safely led to satisfactory positioning in difficult cases and, importantly, improved success rates of PICC placements. MATERIAL AND METHODS: A retrospective study of 1560 patients who underwent US-guided PICC placement were performed. Patients who failed US-guided PICC placement were transferred to the interventional radiology department for fluoroscopically guided tip repositioning. Baseline characteristics as well as insertion-related factors were collected. All data were analyzed using SPSS software. RESULTS: In total, 37 (2.4%) patients who failed US-guided PICC placement accepted fluoroscopically guided adjustment or re-insertion. Of these 37 patients, 32 were enrolled. We observed no significant differences between right and left arm PICC access (P > 0.05), even though a higher percentage of PICCs were inserted into left arms (56.3%). The basilic vein (65.6%) was the most common insertion site. Only four patients experienced slight angiospasm (3.1%) and venous thrombosis (9.4%). US-guided PICC insertion failures were primarily due to line tip malposition (84.4%). All patients successfully underwent fluoroscopically guided tip repositioning, which resulted in optimal catheter tip positioning. PICC lines were adjusted in most patients (n=28, 87.5%). CONCLUSION: Malposition was the primary issue causing US-guided PICC insertion failure. Fluoroscopically guided tip repositioning safely and efficaciously led to satisfactory positioning in difficult cases; thus, we recommend this method for patients failing US-guided PICC placement.
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Cateterismo Venoso Central , Cateterismo Periférico , Cateteres Venosos Centrais , Humanos , Cateterismo Venoso Central/métodos , Estudos Retrospectivos , Reposicionamento de Medicamentos , Cateterismo Periférico/métodos , Catéteres , Ultrassonografia de IntervençãoRESUMO
In quantum anomalous Hall (QAH) insulators, the interior is insulating but electrons can travel with zero resistance along one-dimensional (1D) conducting paths known as chiral edge channels (CECs). These CECs have been predicted to be confined to the 1D edges and exponentially decay in the two-dimensional (2D) bulk. In this Letter, we present the results of a systematic study of QAH devices fashioned in a Hall bar geometry of different widths under gate voltages. At the charge neutral point, the QAH effect persists in a Hall bar device with a width of only â¼72 nm, implying the intrinsic decaying length of CECs is less than â¼36 nm. In the electron-doped regime, we find that the Hall resistance deviates quickly from the quantized value when the sample width is less than 1 µm. Our theoretical calculations suggest that the wave function of CEC first decays exponentially and then shows a long tail due to disorder-induced bulk states. Therefore, the deviation from the quantized Hall resistance in narrow QAH samples originates from the interaction between two opposite CECs mediated by disorder-induced bulk states in QAH insulators, consistent with our experimental observations.