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Metallic barcode nanowires (BNWs) composed of repeating heterogeneous segments fabricated by template-assisted electrodeposition can offer extended functionality in magnetic, electrical, mechanical, and biomedical applications. The authors consider such nanostructures as a 3D system of magnetically interacting elements with magnetic behavior strongly affected by complex magnetostatic interactions. This study discusses the influence of geometrical parameters of segments on the character of their interactions and the overall magnetic behavior of the array of BNWs having alternating magnetization, because the Fe and Au segments are made of Fe-Au alloys with high and low magnetizations. By controlling the applied current densities and the elapsed time in the electrodeposition, the dimension of the Fe-Au BNWs can be regulated. This study reveals that the influence of the length of magnetically weak Au segments on the interaction field between nanowires is different for samples with magnetically strong 100 and 200 nm long Fe segments using the first-order reversal curve (FORC) diagram method. With the help of micromagnetic simulations, three types of magnetostatic interactions in the BNW arrays are discovered and analy. This study demonstrates that the dominating type of interaction depends on the geometric parameters of the Fe and Au segments and the interwire and intrawire distances.
Assuntos
Nanoestruturas , Nanofios , Nanofios/química , Nanoestruturas/química , Galvanoplastia/métodos , MagnetismoRESUMO
BACKGROUND: Many patients report discomfort because of the unpleasant taste of bowel preparation solutions. OBJECTIVE: This study aimed to determine whether adding orange juice to 2 L of polyethylene glycol plus ascorbic acid is effective for reducing patient discomfort and improving palatability during bowel preparation. DESIGN: This was a single-blinded, randomized controlled trial. SETTINGS: The study was conducted at a tertiary referral hospital and a generalized hospital. PATIENTS: Consecutive outpatients and inpatients were randomly allocated to drink 2 L of polyethylene glycol-ascorbic acid or 2 L of polyethylene glycol-ascorbic acid with orange juice in a single dose or a split dose. MAIN OUTCOME MEASURES: Tolerability, palatability score, willingness, and related adverse events were investigated by questionnaires. Bowel cleansing was rated using the Aronchick scale. Each score was graded on a 5-point scale. RESULTS: A total of 107 patients, 53 in the orange juice group and 54 in the polyethylene glycol-ascorbic acid group who underwent elective colonoscopy were enrolled. The palatability score (mean ± SD) was higher in the orange juice group than in the control group (2.36 ± 0.76 vs 1.78 ± 0.88; p = 0.005). Nausea was less frequent in the orange juice group (26.4% vs 59.3%; p = 0.001). Total amount of bowel preparation ingested was not significantly different between the groups (p = 0.44). The bowel preparation score (mean ± SD) was not significantly different (1.49 ± 0.80 vs 1.43 ± 0.77; p = 0.94). Willingness to repeat the same process was higher in the orange juice group (90.4% vs 66.7%; p = 0.003). LIMITATIONS: This study is limited because only ambulatory patients were enrolled. CONCLUSIONS: Orange juice intake before drinking 2 L of polyethylene glycol-ascorbic acid for colonoscopy can reduce patient discomfort, resulting in improved acceptability and patient compliance. This method is as effective for bowel cleansing as polyethylene glycol.
Assuntos
Bebidas , Catárticos/administração & dosagem , Citrus , Preferência do Paciente , Polietilenoglicóis/administração & dosagem , Paladar , Adulto , Idoso , Ácido Ascórbico/administração & dosagem , Ácido Ascórbico/efeitos adversos , Bebidas/efeitos adversos , Catárticos/efeitos adversos , Citrus/efeitos adversos , Pólipos do Colo/diagnóstico , Colonoscopia/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Náusea/induzido quimicamente , Polietilenoglicóis/efeitos adversos , Método Simples-Cego , Inquéritos e Questionários , Vitaminas/administração & dosagem , Vitaminas/efeitos adversosRESUMO
In the crystallisation of nanomaterials, an assembly-based mechanism termed 'oriented attachment' (OA) has recently been recognised as an alternative mechanism of crystal growth that cannot be explained by the classical theory. However, attachment alignment during OA is not currently tuneable because its mechanism is poorly understood. Here, we identify the crystallographic disorder-order transitions in the OA of magnetite (Fe3O4) mesocrystals depending on the types of organic surface ligands on the building blocks, which produce different grain structures. We find that alignment variations induced by different surface ligands are guided by surface energy anisotropy reduction and surface deformation. Further, we determine the effects of alignment-dependent magnetic interactions between building blocks on the global magnetic properties of mesocrystals and their chains. These results revisit the driving force of OA and provide an approach for chemically controlling the crystallographic order in colloidal nanocrystalline materials directly related to grain engineering.
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Quantifying the spin-orbit torque (SOT) efficiency with changing the layer thickness is crucial for understanding the physical background of SOT. This study investigates the Nb-thickness-dependent SOT efficiency of two types of layered heterostructures: Ta/Nb/CoFeB and Pt/Nb/CoFeB. We find that the Nb thickness dependence of the SOT efficiency in the two samples is quite different. In the Pt/Nb series, the SOT sign changes according to the thickness variation because Pt and Nb have different spin-orbit coupling signs. We observe the resulting reversal in switching polarity through current-induced SOT switching experiments. However, due to the same spin-orbit coupling signs of Ta and Nb, no such polarity reversal was observed in Ta/Nb series. Further, we extract the spin diffusion length of Nb in each heterostructure. These results provide a systematic understanding of the material- and thickness-dependent SOT characteristics.
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The manipulation of magnetization with interfacial modification using various spin-orbit coupling phenomena has been recently revisited due to its scientific and technological potential for next-generation memory devices. Herein, we experimentally and theoretically demonstrate the interfacial Dzyaloshinskii-Moriya interaction characteristics penetrating through a MgO dielectric layer inserted between the Pt and CoFeSiB. The inserted MgO layer seems to function as a chiral exchange interaction mediator of the interfacial Dzyaloshinskii-Moriya interaction from the heavy metal atoms to ferromagnet ones. The potential physical mechanism of the anti-symmetric exchange is based on the tunneling-like behavior of conduction electrons through the semi-conductor-like ultrathin MgO. Such behavior can be correlated with the oscillations of the indirect exchange coupling of the Ruderman-Kittel-Kasuya-Yosida type. From the theoretical demonstration, we could provide approximate estimation and show qualitative trends peculiar to the system under investigation.
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Lymphangioma is an uncommon malformation of the lymphatic system that involves a benign proliferation of the lymphatics, with no established treatment method. Multiple colonic lymphangioma, or colonic lymphangiomatosis, is an extremely rare condition. We report a case of colonic lymphangiomatosis that was detected during a colonoscopic examination conducted as part of a general health check-up. The lesion completely resolved after excisional biopsy.
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Fitz-Hugh-Curtis syndrome is a type of perihepatitis that causes liver capsular infection without infecting the hepatic parenchyma or pelvis. Fitz-Hugh-Curtis syndrome is known to occur commonly in women of childbearing age who do not use oral contraceptives and have sexual partners older than 25 years of age. However, the syndrome has been reported to occur rarely in males. The clinical symptoms are right upper quadrant pain and tenderness, and pleuritic right sided chest pain. The clinical presentation is similar in male and female. We experienced a case of Fitz-Hugh-Curtis syndrome in a 60-year-old man with the chief complaint of right upper quadrant abdominal pain. Despite a previous history of gonorrhea, we have also described our experiences of improved symptoms and recovery with allopathic medicines and have thereby reported the present case with a literature review.
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Strain distribution in compressed tissues gives information about elasticity of the tissues. We have measured strain from two sets of 3D micro-CT images of a breast-mimicking phantom; one obtained without compressing the phantom and the other with compressing it. To measure strain, we first calculated compression-induced displacements of high-intensity feature patterns in the image. In measuring displacement of a pixel of interest, we searched the pixel in the compressed-phantom image, whose surrounding resembles the uncompressed-phantom image most closely, using the image correlation technique. From the displacement data, we calculated average strain at a region of interest. With the calculated average strains, we could distinguish the hard inclusion in the phantom which was not distinguishable from the background body of the phantom in the ordinary micro-CT images. The calculated strains account for stiffness of the tissue of interest, one of the important parameters for diagnosing malignant tissues. We present experimental results of the displacement and strain measurement along with FEM analysis results.