Circular Zone Research Articles

Retinal defocus and form-deprivation induced regional differential gene expression of bone morphogenetic proteins in chick retinal pigment epithelium.

We previously reported bidirectional gene expression regulation of the Bone Morphogenetic Proteins (BMP2, 4, and 7) in chick retinal pigment epithelium (RPE) in response to imposed optical defocus and form-deprivation (FD). This study investigated whether there are local (regional) differences in these effects. 19-day old White-Leghorn chicks wore monocular +10 or - 10 D lenses, or diffusers (FD) for 2 or 48 hr, after which RPE samples were collected from both eyes, from a central circular zone (3 mm radius), and 3 mm wide annular mid-peripheral and peripheral zones in all cases. BMP2, 4, and 7 gene expression levels in RPE from treated and fellow control eyes were compared as well as differences across zones. With the +10 D lens, increased expression of both BMP2 and BMP4 genes was observed in central and mid-peripheral zones but not the peripheral zone after 2 and 48 hr. In contrast, with the -10 D lens BMP2 gene expression was significantly decreased in all three zones after 2 and 48 hr. Similar patterns of BMP2 gene expression were observed in all three zones after 48 hr of FD. Smaller changes were recorded for BMP4 and BMP7 gene expression for both myopia-inducing treatments. That optical defocus- and FD-induced changes in BMP gene expression in chick RPE show treatment-dependent local (regional) differences suggest important differences in the nature and contributions of local retinal and underlying RPE regions to eye growth regulation.

Glaucomatous Macular Vasculature: A Quantitative Analysis

Background: The aim of this study was to evaluate the characteristics of the macular vessel density (VD) and the foveal avascular zone (FAZ) in glaucoma quantitatively using the optical coherence tomography angiography (OCT-A).
 Methods: Twenty-five eyes of 13 patients with primary open angle glaucoma (POAG) and 12 eyes of 6 healthy participants were enrolled retrospectively. Functional visual field (VF) and structural Spectral-Domain optical coherence tomography (SD-OCT) Retinal Nerve Fiber Layer Thickness (RNFLT) were assessed in all participants. OCT-A was performed on a fovea centered, 15x10 degrees, macular region. OCT-A scans were processed with MATLAB software and automatically graded to define FAZ parameters. The parafoveal VD in the superficial and deep retinal vascular plexus (SVP and DVP) was analyzed by quadrant and circular segmented zones.
 Results: Foveal Avascular Zone -Major Axis Length (p=0.02), Area (p=0.04), Equivalent Diameter (p=0.04) and Perimeter (p=0.04) were significantly larger in glaucoma than the control group. Regarding SVP and DVP, the average macular total VD were lower in glaucoma patients compared to the control group (p<0.01; p<0.01). Additionally, the inner circular region (p=0.04; p<0.01 respectively for SVP and DVP) and all quadrants except for North had a lower VD in glaucoma group compared to the control group. Assessment of the total VD successfully predicted RNFLT (p<0.001) and was significantly associated with the probability of glaucoma (p=0.009).
 Conclusion: OCT-A parameters, namely the FAZ morphology and the macular VD, were associated with glaucomatous functional and structural changes. The macular VD showed a considerable diagnostic value. It may be a modern biomarker, representing microvascular network disruption of the macular perfusion in glaucoma.

Cyclic behaviour of steel irregular tubular column panel zones

Abstract The shear strength, shear distortion, failure mode, and energy absorption performance of irregular circular and box-shaped tubular column panel zones (PZs) were investigated using experimental and analytical methods on the seven steel frame structures. The main parameters include the beam height ratio of left and right beams, the column cross-section, and the configuration of external diaphragm. The key variable, beam height ratio, can affect the PZ shear strength and energy absorption, but has little influence on the initial stiffness of the PZ; the PZ, PZ1, and PZ2, absorb energy together in the initial loading stages, as the load increases, most of the energy begins to be absorbed only by PZ1 which has the same height as the smaller beam, therefore, the design considering only PZ1 is incomplete; excessive PZ shear deformation can cause cracking of the weld root which adversely affects the structure; the configuration of external diaphragm should avoid stress concentration which can cause cracking of the base metal. The chosen analysis methods are capable of simulating the shear strength and failure modes of the PZ obtained in experimental results with acceptable accuracy.

Silver Double Nanorings with Circular Hot Zone.

Silver double nanorings with circular intra-nanogaps between two nanorings of different diameters were synthesized without a linker molecule to confine an incident electromagnetic field in a single entity. We used on-demand, rational, and systematic multi-stepwise reactions consisting of (1) selective etching of gold, (2) rim-on deposition of platinum, (3) eccentric growth of gold, and (4) concentric growth of silver. The resulting silver double nanorings exhibited a high degree of homogeneity in both shape and size, with strongly coupled circular hot zones (or "hot halos", referring to the circular intra-nanogaps capable of focusing the near electromagnetic field) resulting from strong surface plasmon coupling between the inner and outer nanorings. Remarkably, these silver double nanorings exhibited strong, stable, and reproducible single-particle surface-enhanced Raman scattering signals without blinking. The signals appeared independently of polarization directions, which is a unique feature of a circular hot halo. The estimated enhancement factor was between 2 × 108 and 7 × 108. The measured limit of detection was 10-7 M in bulk concentration, and the signal appeared 570 s after sample exposure.

Visualization of principal strain direction by a mechanical device

Abstract Generally, the strains at a point must be measured at least in three directions simultaneously in order to find the principal strain. In this paper, a simple device is proposed to visualize the principal strain direction in structure in real-time. Different from the conventional methods, it is able to indicate the principal strain by detecting the largest deformation in the elliptical zone which is deformed from a circular zone. The mechanism and key structure of the device are introduced in detail. The main factors which influence the sensitivity and accuracy of the visualization are analyzed. The fundamental experiments including a uniaxial compression test and the simply supported beam experiment were conducted to verify the validity of the method. It is found that the device can work well to visualize the direction of principal strain.

654-P: Detection of Insulin-Derived Amyloid Deposits and the Management of Insulin Injection Site Using CGM and Abdominal Wall CT Examination

Repetitive injection of insulin causes subcutaneous amyloid deposits leading to impaired blood glucose control due to delayed absorption of the drugs. Amyloid deposits in abdominal wall is detected by CT examinations. Proper selection of the injection site avoiding amyloid deposits is essential. The present study was conducted to establish a novel method for the management of injection site avoiding amyloid deposits. The present study included 50 diabetic patients who were treated with insulin over 5 years. Two weeks CGM was performed using Free Style Libre Pro. In the case of significant day to day variation in blood glucose control, abdominal wall CT examination was performed. In front abdominal wall, 36 small circular zones were set to identify the site of injection, named “no-injection zone” which caused impaired blood glucose control due to delayed absorption of insulin by amyloid deposits. Site rotation seat was developed for the management of insulin injection site. Among 50 patients, 33 patients were shown to have “no-injection zone” (average; 8.5 zones). In the patients whose HbA1c is over 8% (n=15), a significant improvement in HbA1c from 9.0% to 7.8% was observed without any changes in daily dose of long-acting insulins by the management of injection site. The management of injection site using CGM, abdominal CT and site rotation seat improves blood glucose control. Disclosure H. Nishihara: None. T. Sudo: None. J. Sasaki: None. N. Hasegawa: None. M. Ishii: None. C. Koizumi: None. M. Hiraoka: None. S. Ikejima: None. A. Hirai: None. M. Suzuki: None.

Prediction of Surface Subsidence Extension due to Underground Caving: A Case Study of Hemushan Iron Mine in China

Underground caving can potentially lead to large-scale surface destruction. To test the safety conditions of the surface construction projects near the circular surface subsidence zone in the Hemushan Iron Mine, this paper proposes an analytical model to analyze the stability of the cylindrical caved space by employing the long-term strength of the surrounding rock mass, the in situ stress, and the impact of caved materials as inputs. The proposed model is valid for predicting the orientation and depth where rock failure occurs and for calculating the maximum depth of the undercut, above which the surrounding rock mass of the caved space can remain stable for a long duration of time. The prediction for the Hemushan Iron Mine from the proposed model reveals that the construction projects can maintain safe working conditions, and such prediction is also demonstrated by the records from Google Earth satellite images. This means that the proposed model is valid for conducting such analysis. Additionally, to prevent rock failure above the free surface of caved materials, backfilling the subsidence zone with waste rocks is suggested, and such a measure is implemented in the Hemushan Iron Mine. The monitoring results show that this measure contributes to protecting the surrounding wall of the caved space from large-scale slip failure. The contribution of this work not only provides a robust analytical model for predicting the stability of rock around a cylindrical caved space but also introduces employable measures for mitigating the subsequent extension of surface subsidence after vertical caving.

Ultrastructural Studies on a Model Tintinnid - Schmidingerella meunieri (Kofoid & Campbell, 1929) Agatha & Strüder-Kypke, 2012 (Ciliophora). II. The Oral Apparatus.

The ultrastructure of the oral apparatus is supposed to be significant for elucidating more recent common ancestry and might thus provide support for particular groupings of oligotrichean ciliates. The transmission electron microscopical study on mainly cryofixed Schmidingerella meunieri specimens provides the first detailed data for tintinnids and Oligotrichea in general. Ten new characters are included into the cladistic analysis. These features together with the very limited body of literature suggest that substantial changes in the oral ultrastructure correlate only with the formation of a circular adoral zone in choreotrichids. Despite homoplasious morphological and ontogenetic adaptations to the planktonic lifestyle in halteriid hypotrichs and oligotrichids, their oral apparatuses generally retain the plesiomorphic ultrastructure of the Perilemmaphora. The highly complex ultrastructure of the adoral zone is thus able to accomplish an extension in the zone's functionality without obvious changes; only the position of the adoral zone at the apical cell portion together with a globular to obconical cell shape are apparently crucial. Merely, minute apomorphies characterise the Oligotrichea and tintinnids, respectively. Tintinnids with derived somatic ciliary patterns possess distinct microtubular bundles connecting the oral apparatus with the myoneme in the peduncle.

Strength of scarf-bonded CFRP repairs containing disc-shaped zones of weak bonding considering hot-wet conditioning

A commonly used design for the repair of carbon fibre reinforced polymers (CFRP) is the bonded scarf joint. As contaminations on the adherend surface or bondline flaws can reduce the bonding strength drastically, the effect of such strength reducing phenomena has to be known. This is also the case for bonded joints that had to sustain hot-wet conditions. Therefore, the aim of this study was to investigate the influence of weak bonds and hot-wet conditioning on the mechanical properties of scarf bonded CFRP joints. Circular zones of weak bonding have been artificially produced by application of release agent on the adherend surface. Different sizes and locations were studied. Additionally, two scarf ratios and two lay-ups have been investigated, to account for different stress states in the bondline. The investigation showed that the effect of a weak bond on bond strength is strongly dependent on the location, size and lay-up of the adherend, while hot-wet conditioning reduces the bond strength in all cases.

Floriform cataract

A 6-year-old girl presented with decreased vision in the right eye detected during a school-screening program. The best-corrected visual acuity was 20/120 in the right eye and 20/20 in the left eye. On retro-illumination, there were petal-shaped opacities arranged in a flower-like pattern. Prominent embryonic suture lines separating the petals completed the “floriform” pattern. A peripheral circular zone of lenticular haze with a few spokes or “riders” was also present. She was diagnosed as having a floriform cataract, a rare subtype of congenital cataract with an autosomal dominant inheritance. Patient regained 20/40 vision in the affected eye after cataract surgery.

Analysis on construction of the subway shield underpassing the underground pedestrian passage at close range

Numerical simulation analysis was conducted on the shield tunneling construction of the right line between Tangdong station and Huangcun station of Guangzhou rail transit line 21, the right line subway shield underpassing the underground pedestrian passage at close range. The numerical simulation vertical settlement of the ground and floor outside the foundation pit was compared with the field monitoring. The results show that the numerical analysis of the trend of land subsidence is consistent with the field monitoring, the thickness of the tunnel roof overburden has a great influence on the ground settlement. The ground settlement is mainly subsidence with thick overburden, while the thin overburden, the ground settlement is mainly uplift; the Equivalent Circular Zone formed by simultaneous grouting and secondary grouting has a great influence on the ground settlement. During the site construction, the tunneling parameters should be adjusted according to the site monitoring, and parameters such as soil and water pressure on the tunneling surface, overburden thickness, synchronous grouting pressure and secondary grouting pressure should be taken into comprehensive consideration to control the tunneling of shield underpassing the existing structures at close range.

Altered Distribution of Interstitial Cells of Cajal in Normoganglionic and Transitional Zone of Hirschsprung Disease and Their Clinical Significance

Objective − The aim of this study was to evaluate interstitial cells of Cajal (ICC) in Hirschsprung disease (HD), especially in children who had postsurgical problems. Material and Methods − The study included tissue samples of normoganglionic (NZ) and transitional zone (TZ) of 33 HD pediatric patients. Samples of bowel from 10 autopsy controls who did not have dysmotility were also analyzed. Hematoxylin-eosin (H&E) and immunohistochemical (MAP-2 and c-Kit (CD117)) staining were performed. Myenteric ganglia were analyzed at 5 microscopic fields H&E and MAP-2 stained sections (magnification 400×). The diameters of the submucosal nerves were measured at 3 microscopic H&E fields (magnification 400×). The ICC were analyzed on c-Kit immunostained slides at 3 microscopic fields per each bowel layer (magnification 200×): deep submucosa, circular and longitudinal muscular layer and zone of myenteric plexus. Results − The myenteric ganglion cell count was significantly lower in TZ of all children with HD, while there were no significant differences in NZ between the study group and age-matched controls. The ICC network was affected in all cases of HD. The total ICC count was significantly lower in NZ than in control (P<0.001). A critically lower ICC count (<50% of minimal ICC count in the control group) in the NZ was found in patients with postoperative problems (constipation and enterocolitis). Conclusion − Decreased count of the ICC in the NZ could be the cause of intestinal motility difficulties in the postoperative period in children with HD.

A Circular Inclusion and Two Radial Coaxial Cracks with Contacting Faces in a Piecewise Homogeneous Isotropic Plate Under Bending

Abstract The bending problem of an infinite, piecewise homogeneous, isotropic plate with circular interfacial zone and two coaxial radial cracks is solved on the assumption of crack closure along a line on the plate surface. Using the theory of functions of a complex variable, complex potentials and a superposition of plane problem of the elasticity theory and plate bending problem, the solution is obtained in the form of a system of singular integral equations, which is numerically solved after reducing to a system of linear algebraic equations by the mechanical quadrature method. Numerical results are presented for the forces and moments intensity factors, contact forces between crack faces and critical load for various geometrical and mechanical task parameters.

Ablation behavior of SiCp/AA2024 composites irradiated by a single-pulse nanosecond laser

In this study, homogenous Al alloy and SiC materials and SiCp/AA2024 composites with mean particle diameters of 5 μm and 30 μm were irradiated by a single-pulse nanosecond fiber laser with a 200 ns pulse width and 1064 nm wavelength. Using a laser pulse, regular circular heat-affected zones (HAZ) were formed in the homogenous materials. For the composites, an Al allloy matrix was melted and sputtered, and the SiC particles bulged when irradiated by the laser pulse. According to the measured results, the HAZ increased with the pulse energy density in a logarithmic pattern. Nonlinear fitting results demonstrated that the damage thresholds of the composites and SiC homogenous materials were the lowest and highest, respectively. SiCp/AA2024 composites with different mean particle diameters exhibited similar damage thresholds. The measured etching depths of the SiC particles and Al alloy matrix were smaller than the respective values of the homogenous materials. Thermal simulation results revealed that thermal-mechanical coupling occurred between the SiC particles and Al alloy matrix. The SiC particles in the composite heated more rapidly under a nanosecond laser, and the heat was then transferred to the matrix. Large SiC particles constrained the matrix’s molten pool, which accelerated its gasification but hindered further etching.

Colorimetric aggregation assay based on array of gold and silver nanoparticles for simultaneous analysis of aflatoxins, ochratoxin and zearalenone by using chemometric analysis and paper based analytical devices.

A paper based sensor array ispresented to discriminate and determine five mycotoxins classified into three categories, namely aflatoxins, ochratoxins and zearalenone. The gold and silver nanoparticles, synthesized by three different reducing or capping agents, were employed as sensing elements of thefabricated device. These nanoparticles were poured onto hydrophilic circular zones embedded on the hydrophobic substrate. The response of the assay is dependent on the aggregation of nanoparticles for interaction with mycotoxins. Due to aggregation, the gold and silver nanoparticles changed to purple and brown, respectively. Color changes provide unique colorimetric signatures conducive to recognizing the type of mycotoxin, identifying its chemical structure, and finding the fungi that produce it. The discrimination ability of the assay was investigated by both supervised (linear discriminate analysis) and unsupervised (principle component analysis and hierarchical cluster analysis) pattern recognition methods. The assay was applied to the point of need determination of aflatoxin B1, aflatoxin G1, aflatoxin M1, ochratoxin A and zearalenone with a detection limit of 2.7, 7.3, 2.1, 3.3 and 7.0ng.mL-1, respectively. The fabricated device has highpotential of simultaneously determining the mycotoxins in pistachio, wheat, coffee and milk with the help of partial least square method. The root mean square errors for prediction of PLS model were 5.7, 5.2, 1.5, 7.2 and 2.9 for aflatoxin B1, aflatoxin G1, aflatoxin M1, ochratoxin A and zearalenone, respectively. Graphical abstractSchematic representation of paper based colorimetric sensor array based on gold and silver nanoparticles for both qualitative and quantitative analysis of aflatoxins, ochratoxin and zearalenone.

Effect of tilt on circular zone plate performance.

Fresnel zone plates are frequently used as focusing and imaging optics in x-ray microscopy, as they provide the ease of use of normal incidence optics. We consider here the effects of tilt misalignment on their optical performance, both in the thin optics limit and in the case of zone plates that are sufficiently thick so that volume diffraction effects come into play. Using multislice propagation, we show that simple analytical models describe the tilt sensitivity of thin zone plates and the thickness at which volume diffraction must be considered, and examine numerically the performance of example zone plates for soft x-ray focusing at 0.5 keV and hard x-ray focusing at 10 keV.

Research on resource and environment evaluation of Qaidam Circular Economy Experimental Zone

China’s economy is growing rapidly, and the demand for resources and its dependence on foreign countries continue to increase. Exploring the status quo between the regional economy, resource utilization, and environmental protection will improve economic development while protecting the environment and become sustainable development. This paper uses the economic data, “three wastes” emission data, enterprise resource data, and social resource data on the Qaidam Circular Economy ExperimentalZone from 2005 to 2017, and uses the entropy weight method to weight the data and then uses the comprehensive evaluation method to evaluate the data. According to the current situation, it is concluded that the industrialized and green development of the experimental zone has achieved remarkable results, and the management and control of the experimental zone management committee is crucial to the development of the experimental zone.

Vertebral column deformity with curved cross-stitch vertebrae in Norwegian seawater-farmed Atlantic salmon, Salmo salar L.

Pathological changes in the vertebral column of farmed Atlantic salmon in Norway have been reported since the 1990s. Based on the characteristic radiographic findings, we here present a vertebral column deformity named "curved cross-stitch vertebrae" that mainly affects the middle aspect of the vertebral column. Sixty fish, from the west/northwest coast of mid-Norway, were sampled at slaughter and examined by radiography, computed tomography (CT), necropsy, macrophotography, and histology. The vertebral deformities were radiographically graded as mild, moderate, or marked. The main differences between these grades of changes were defined by increased curving of the peripheries of endplates, reduced intervertebral spaces, and vertical displacement of the vertebrae. The curved rims of endplates were located peripheral to a continuous and approximately circular borderline. The CT studies revealed small, multifocal, hypo-attenuating, round to crescent-shaped areas in the notochord, compatible with the presence of gas. Additionally, histology revealed that the axial parts of endplates had circular zones with perforations, through which either notochordal tissue prolapsed into the vertebrae or vascularized fibrochondroid proliferations extended from the vertebrae into the notochord. Inflammation was present in many vertebral bodies. To the best of our knowledge, this is the first report of gas in the notochord of fish.

Research on Objective Environmental Factors of Sustainable Development of Enterprises in Qaidam Circular Economy Pilot Area

The sustainable development of the industrial enterprises in the Qaidam Circular Economy Pilot Zone must meet both the current needs and the future development, as well as the economic and ecological development, as well as the dual development of industrial enterprises and regions. For the industrial enterprises in the experimental area, in order to ensure sustainable development, their own strategies and efforts are very important, but in a policy-dependent area like Haixi Prefecture, the influencing factors of the objective environment are more important. The impact of sustainable development of HaiXi industrial enterprises is of great practical significance. Therefore, according to the subjectivity of Haixi Prefecture and the experimental area and the nature of industrial enterprises, the objective environmental factors are divided into four categories: regional development, regional material resources, regional greening, and regional security. In the end, it was concluded that industrial enterprises in the test area not only need to pay attention to the restraint of their sustainable development in terms of brain drain, energy consumption and environmental greening, but also continue to maintain the role of regional development and regional security in promoting their sustainable development.

Simple and fast fabrication of microfluidic paper-based analytical device by contact stamping for multiple-point standard addition assay: Application to direct analysis of urinary creatinine

In this work, a microfluidic paper-based analytical device (μPAD) for simultaneous multiple-point standard addition assay was fabricated by rubber stamping the hydrophobic barrier pattern onto a laboratory filter paper. The μPAD has a central zone from which an applied sample flows into eight surrounding narrow channels to which had been added the standard solutions. Each channel is connected to a circular area loaded with the reagent. The opposite end of this reagent zone is connected by second narrow channel to the final circular detection zone. The μPAD was applied to the measurement of creatinine in human urine. After addition of a urine sample, the orange-colored product arising from the Jaffé reaction is formed at the eight detection zones. A digital image of the μPAD is then recorded and the ratio of the red/green (R/G) intensity obtained using the ImageJ™ program is used in the quantitation of creatinine. The normal standard addition calibration line is constructed using the intensity ratio against the added creatinine concentrations (50–1000 mg L−1). Good linearity was achieved (r2 ˃ 0.99). There were no significant differences between the creatinine content using an HPLC method (paired t-test at 95% confidence, tstat = 1.78, tcritical = 2.26, n = 10). The use of simultaneous multiple-point standard addition calibration allows rapid determination of creatinine in urine with elimination of matrix interference.