587 research outputs found

    The role of 99mTc-Ubiquicidin (UBI) and 99mTc-IgG scintigraphies in diagnosis of acute appendicitis: A preliminary result

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    Introduction: Appendicitis is one of the most common surgical emergencies. In spite of the relatively high rate of negative appendectomy, as a result of miss diagnosis, uncertainty of diagnosis still continues to challenge physicians. The objective of this prospective study was to investigate the role of 99mTc-Ubiquicidin (UBI) scintigraphy in the diagnosis of acute appendicitis and to compare 99mTc-UBI scintigraphy with 99mTc-IgG scintigraphy. Methods: Twelve patients with right lower quadrant pain and suspicious of acute appendicitis were referred to the nuclear medicine imaging center. Radionuclide imaging was performed with 99mTc-UBI in 8 and 99mTc-IgG in 4 patients. Ultrasonography, Alvarado scoring and histopathological examinations were also performed as additional diagnostic tests. Results: Reports from 99mTc-IgG and 99mTc-UBI scintigraphies of all patients were negative. Conclusion: This study may conclude that 99mTc-IgG scintigraphy and 99mTc-UBI scintigraphy in the detection of appendicitis do not have adequate efficacy. However, in order to better evaluate 99mTc-IgG and 99mTc-UBI scintigraphy, a comprehensive study on a large number of patients with clinical suspicious of acute appendicitis would be more helpful

    Single-photon nonlinear optics with a quantum dot in a waveguide

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    Strong nonlinear interactions between photons enable logic operations for both classical and quantum-information technology. Unfortunately, nonlinear interactions are usually feeble and therefore all-optical logic gates tend to be inefficient. A quantum emitter deterministically coupled to a propagating mode fundamentally changes the situation, since each photon inevitably interacts with the emitter, and highly correlated many-photon states may be created . Here we show that a single quantum dot in a photonic-crystal waveguide can be utilized as a giant nonlinearity sensitive at the single-photon level. The nonlinear response is revealed from the intensity and quantum statistics of the scattered photons, and contains contributions from an entangled photon-photon bound state. The quantum nonlinearity will find immediate applications for deterministic Bell-state measurements and single-photon transistors and paves the way to scalable waveguide-based photonic quantum-computing architectures

    Analysis of Soil-Compacting Effect Caused by Shield Tunneling Using Three-Dimensional Elastoplastic Solution of Cylindrical Cavity Expansion

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    This is the final version of the article. Available from Hindawi via the DOI in this record.Soil squeezing effect and formation disturbance caused by tunnel excavation can be simulated by cylindrical cavity expansion due to the comparability between tunneling and cavity expansion. Although most of the existing theoretical derivation is based on simple constitutive model of soil foundation, not only the relation between principal stress components was simplified in the solution process, but also the stress history, initial stress anisotropy, and stress-induced anisotropy of structural soil were neglected. The mechanical characteristics of soil are closely related to its stress history, so there is a gap between the above research and the actual engineering conditions. A three-dimensional elastoplastic solution of cylindrical cavity expansion is obtained based on the theory of critical state soil mechanics and engineering characteristics of shield tunneling. In order to fully consider the influence of initial anisotropy and induced anisotropy on the mechanical behavior of soils, the soil elastoplastic constitutive relation of cavity expansion is described in the course of K0-based modified Cam-clay (K0-MCC) model after soil yielding. An equation with equal number of variables is obtained under the elastic-plastic boundary condition based on the Lagrange multiplier method. By solving the extreme value of the original function, the analytical solution of radial, tangential, and vertical effective stresses distribution around the circular tunnel excavation is obtained. In addition, changes of elastic deformation area and plastic deformation area for soil during the shield excavation have been analyzed. Calculation results are compared with the numerical solutions which usually consider isotropic soil behavior as the basic assumption. In this paper, a constitutive model which is more consistent with the actual mechanical behavior of the soil and the construction process of the shield tunnel is considered. Therefore, the numerical solutions are more realistic and suitable for the shield excavation analysis and can provide theoretical guidance required for design of shield tunneling.This work is supported by the National Natural Science Foundation of China (no. 41172238)

    Computational Modelling of Braided Fibre for Concrete Reinforcement

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    This paper presents numerical modelling of braided fibre, to be used as concrete reinforcement. Ultimately, a corrosive and fire resistant concrete will be produced. A Cubit script (geometry and mesh software) was created to mesh braided yarns under dierent geometric parameters. Fibres were represented using elastic transversely isotropic materials, for which the fibre directions for every yarn were precisely determined from the gradients of the resultant stream functions of potential flow problems. Applying an elastic interfaces between yarns to preventing penetration and having free sliding, convergence studies were conducted on a coarse and fine mesh, using hierarchical higher order approximation [1] for uniform p- and hp-refinement

    Sister chromatid exchange in peripheral blood lymphocytes as a possible breast cancer risk biomarker: A study of Iranian patients with breast cancer

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    Introduction: Sister chromatid exchanges (SCEs) can be induced by variousgenotoxic treatments, suggesting that SCEs refl ect a DNA repair process and it may be a good index for assessment of genomic instability. However, the occurrence of genetic instability and in particular, of spontaneous SCEs has been strongly linked to cancer. Several chromosomal regions and many genes have been implicated in breast cancer.Materials and Methods: Blood samples were obtained from 31 Iranian breast cancer patients and 11 healthy women. SCE was measured in peripheral blood lymphocytes by adding to Ham’sF10 medium in presence of PHA, BrdU (5-bromo-deoxy Uridine) fl uorochrome Hoechst 33258, exposure to UV light and Giemsa staining. Then, SCE frequencies of patient and control groups were compared by the Mann-Withney U-test.Results: Signifi cantly difference was observed between two groups (

    Theta Phase-dependent Modulation of Perception by Concurrent Transcranial Alternating Current Stimulation and Periodic Visual Stimulation

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    Background: Sensory perception can be modulated by the phase of neural oscillations, especially in the theta and alpha ranges. Oscillatory activity in the visual cortex can be entrained by transcranial alternating current stimulation (tACS) as well as periodic visual stimulation (i.e., flicker). Combined tACS and visual flicker stimulation modulates blood- oxygen-level-dependent (BOLD) responses and concurrent 4 Hz auditory click-trains and tACS modulates auditory perception in a phase-dependent way. Objective: In the present study, we investigated if phase synchrony between concurrent tACS and periodic visual stimulation (i.e., flicker) can modulate performance on a visual matching task. Methods: Participants completed a visual matching task on a flickering visual stimulus while receiving either in-phase (0°) or asynchronous (180°, 90°, or 270°) tACS at alpha or theta frequency. Stimulation was applied over either occipital cortex or dorsolateral prefrontal cortex (DLPFC). Results: Visual performance was significantly better during theta frequency tACS over the visual cortex when it was in-phase (0°) with visual stimulus flicker, compared to anti-phase (180°). This effect did not appear with alpha frequency flicker or with DLPFC stimulation. Furthermore, a control sham group showed no effect. There were no significant performance differences amongst the asynchronous (180°, 90°, and 270°) phase conditions. Conclusion: Extending previous studies on visual and auditory perception, our results support a crucial role of oscillatory phase in sensory perception and demonstrate a behaviourally relevant combination of visual flicker and tACS. The spatial and frequency specificity of our results have implications for research on the functional organisation of perception

    The Duration of the Trial Influences the Effects of Mineral Deficiency and the Effective Phytase Dose in Broilers' Diets

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    [EN] Two trials varying in duration (short- and long-term) were conducted to evaluate the effects of providing deficient (NC) or sufficient (PC) Ca and P levels, and different doses of a new phytase (250, 500, and 1000 FTU/kg feed), in broiler feed on growth performance, nutrient digestibility and retention, and tibia mineralization. A total of 80 and 490 male chicks (Ross) of 21 and 1 days of age were used in the short- and long-term trials, respectively. In the long-term trial, chicks fed NC diets showed a lower (p < 0.05) average daily gain and feed intake compared to chicks fed PC and a greater (p < 0.05) feed conversion ratio compared to 500 and 1000 FTU/kg feed during the starting period. Regarding the effects on minerals¿ and nutrients¿ coefficients of retention, animals fed NC showed a significantly higher digestibility for P than those fed the PC diet in the long-term trial. Additionally, feeding 250 to 500 FTU/kg diets increased most of the nutrients¿ digestibility in the short-term but only P digestibility in the long-term trial. Tibia mineralization increased linearly with phytase addition (p < 0.05) only in the long-term trial. In conclusion, the effects of dietary mineral and phytase levels on growth performance are more noticeable in young animals. In addition, the duration of the trial is key due to a possible adaptation phenomenon of birds to low P supplementary levels.This research was funded by the Centre for the Development of Industrial Technology (CDTI), supported by the Ministry of Science and Innovation, Government of Spain.Javadi, M.; Cerisuelo, A.; Cambra López, M.; Macias-Vidal, J.; Donadeu, A.; Dupuy, J.; Carpintero, L.... (2022). The Duration of the Trial Influences the Effects of Mineral Deficiency and the Effective Phytase Dose in Broilers' Diets. Animals. 12(11):1-19. https://doi.org/10.3390/ani12111418119121

    Effects of acute exercise intensity on source episodic memory and metamemory accuracy

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    Prior research suggests that behavioural (e.g., exercise) and psychological factors (e.g., metamemory; monitoring and control of one’s memory processes) may influence memory function. However, there is conflicting results on the optimal intensity of acute exercise to enhance memory and whether acute exercise can also enhance metamemory. Furthermore, very limited research has evaluated whether acute exercise can influence source episodic memory. The objective of this study was to evaluate whether there is an intensity-specific effect of acute exercise on source episodic memory and metamemory accuracy. Thirty young adults participated in a three-condition (control/moderate/vigorousintensity exercise), within-subject counterbalanced experimental study. After each intervention, participants completed source episodic memory and metamemory tasks. Results demonstrated that acute exercise, relative to control, was effective in enhancing source episodic memory, but not metamemory accuracy. Vigorous-intensity acute exercise was the most optimal intensity to enhance source episodic memory. Overall, our findings suggest that there is an intensityspecific effect of acute exercise on source episodic memory. Furthermore, when exercise-related improvements in memory occur, young adults may be unaware of these memory benefits from exercise

    The Astrophysical Distance Scale: V. A 2% Distance to the Local Group Spiral M33 via the JAGB Method, Tip of the Red Giant Branch, and Leavitt Law

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    The J-region asymptotic giant branch (JAGB) method is a new standard candle that is based on the stable intrinsic J-band magnitude of color-selected carbon stars, and has a precision comparable to other primary distance indicators such as Cepheids and the TRGB. We further test the accuracy of the JAGB method in the Local Group Galaxy M33. M33's moderate inclination, low metallicity, and nearby proximity make it an ideal laboratory for tests of systematics in local distance indicators. Using high-precision optical BVI and near-infrared JHK photometry, we explore the application of three independent distance indicators: the JAGB method, the Cepheid Leavitt Law, and the TRGB. We find: μ0\mu_0 (TRGB I) = 24.72 +/- 0.02 (stat) +/- 0.07 (sys) mag, μ0\mu_0 (TRGB NIR) = 24.72 +/- 0.04 (stat) +/- 0.10 (sys) mag, μ0\mu_0 (JAGB) = 24.67 +/- 0.03 (stat) +/- 0.04 (sys) mag, μ0\mu_0 (Cepheid) = 24.71 +/- 0.04 (stat) +/- 0.01 (sys) mag. For the first time, we also directly compare a JAGB distance using ground-based and space-based photometry. We measure: μ0\mu_0 (JAGB F110W) = 24.71 +/- 0.06 (stat) +/- 0.05 (sys) mag using the (F814-F110W) color combination to effectively isolate the JAGB stars. In this paper, we measure a distance to M33 accurate to 2% and provide further evidence that the JAGB method is a powerful extragalactic distance indicator that can effectively probe a local measurement of the Hubble constant using spaced-based observations. We expect to measure the Hubble constant via the JAGB method in the near future, using observations from JWST.Comment: 23 pages, 14 figures, accepted to the ApJ. v2 is exactly the same as v1 except for a fixed minor typo found while looking at the proof

    Investigation of FIH-1 and SOCS3 expression in KRAS mutant and wild-type patients with colorectal cancer

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    Colorectal cancer (CRC) is a multistep process based on the accumulation of somatic mutations in genes such as APC and KRAS. Data on the presence of mutations in KRAS gene in CRC and its relationship with clinicopathological parameters and expression of genes involved in tumor progression are scarce. We unbiasedly examined the KRAS status in samples from 99 patients and its correlation with clinicopathological parameters such as age, sex, tumor location, lymph node metastasis, tumor stage, tumor grade, and vascular invasion. Consistent with reports of other researchers, 38.4 of our samples harbored KRAS mutation in their genomes with preferential mutation in codon 12 (89.4 ). Nevertheless, unlike previous reports, we were not able to correlate KRAS status with clinicopathological parameters (P > 0.05) except for vascular invasion. Patients with KRAS mutation have more vascular invasion compared with patient having wild-type KRAS. Next, we investigated the expression of two tumor suppressor genes, factor-inhibiting hypoxia-inducible factor 1 (FIH-1) and suppressor of cytokine signaling (SOCS3), in both KRAS mutant and wild-type groups and looked for any correlation between their expression and clinicopathological parameters. Although the expression of both genes was not regular, none of the clinicopathological parameters were associated with the expressions of FIH-1 and SOCS3 at mRNA level (P > 0.05). However, decline in FIH-1 expression at protein level in KRAS mutant group was correlated with stage IV and grade 2 of tumor (P � 0.05). Our results demonstrated that there is no or low correlation between KRAS status, FIH-1, and SOCS3 expression with epidemiologic and clinicpathological characteristics in CRC. © 2016, International Society of Oncology and BioMarkers (ISOBM)
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