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Objective The Prydz Bay belt in East Antarctica recorded two significant tectono-thermal events, the Grenvillian event and the Pan-African event, which are considered to be closely related to the evolution of the Rodinia and Gondwana supercontinents. However, the geological history and the tectonic nature of the two events remain controversial. Methods Mineralogical and petrological analyses, phase equilibria modelling and zircon geochronology are combined to investigate the spinel−cordierite granulite from the Mirror Peninsula in order to better understand the tectono-thermal history of the Prydz Bay belt. Results The spinel−cordierite granulite contains different stages of mineral assemblages. The major stage of mineral assemblage involves cordierite, spinel, biotite, sillimanite, K-feldspar and minor garnet and ilmenite. The later stage of mineral assemblage is indicated by the emergence of magnetite as the increasing volumes of biotite and cordierite. Minor garnet and corundum are locally preserved, implying the mineral reaction ‘g+cor→sp+sill’ and more garnet and corundum in the peak stage. The garnet grains consist of 70%−72% almandine, 20%−22% pyrope, ~4% grossularite and ~4% spessartine. The XFe (Fe2+/(Fe2++Mg2+)) of representative garnet grains ranges from 0.77 to 0.80. The spinel exhibits an XFe range from 0.80 to 0.86. Different cordierite grains have similar compositions with Al of 3.89−3.93 a.p.f.u (atoms per formula unit) and XFe of 0.32−0.36. Biotite has high TiO2 (4.13%−5.23%) and Ti (0.23−0.30 a.p.f.u). K-feldspar grains consist of 78%−85% orthoclase, 15%−23% albite and ~1% anorthite. Based on the mineral compositions and phase equilibrium modelling, the pressure−temperature (P−T) conditions of the major stage of mineral assemblage are constrained to 870−910 °C and 0.64−0.69 GPa, followed by later retrogression to 810−820°C and 0.49−0.53 GPa. A peak stage with higher P−T conditions (T>910 ℃, P>0.69 GPa) can be inferred based on the relict peak minerals and characteristic mineral compositions (e.g. Ti in biotite). Zircon grains commonly show core-mantle-rim structures in cathodoluminescence (CL) images. The LA−ICP−MS zircon U−Pb dating analyses reveal a wide age range from 613±7 Ma to 877±9 Ma (except a maximum of 916±11 Ma) for the cores. The zircon bright rims yield a weighted mean age of 526±8 Ma with a wide range of Th/U (0.06−1.23), mostly higher than 0.1. Conclusion Based on the results, a few conclusions can be drawn: (1) The spinel−cordierite granulite recorded medium−low pressure/high-ultrahigh temperature metamorphism with a clockwise P−T evolution path and high dT/dP. (2) The results of zircon geochronological analysis show that zircon cores mainly record U−Pb ages in the range of 800~600 Ma, younger than typical ages of Grenvillian events, which may reflect younger inherited zircon cores or significant isotopic resetting. (3) The age of ~530 Ma of zircon rims is interpreted to represent the post-peak cooling stage of the Pan-African tectono-thermal event. [Significance] This study examined the P−T conditions and the zircon ages of the spinel−cordierite granulite in the Mirror Peninsula. In combination with previous results, the P−T−t path constructed for the spinel−cordierite granulite provides new constraints on the evolution of the Prydz Bay belt during the Pan-African period.

[Objective] The Prydz Bay belt in East Antarctica recorded two significant tectono-thermal events, the Grenvillian event and the Pan-African event, which are considered to be closely related to the evolution of the Rodinia and Gondwana supercontinents. However, the geological history and the tectonic nature of the two events remain controversial. [Methods] Mineralogical and petrological analyses, phase equilibria modelling and zircon geochronology are combined to investigate the spinel-cordierite granulite from the Mirror Peninsula in order to better understand the tectono-thermal history of the Prydz Bay belt. [Results] The spinel-cordierite granulite contains different stages of mineral assemblages. The major stage of mineral assemblage involves cordierite, spinel, biotite, sillimanite, K-feldspar and minor garnet and ilmenite. The later stage of mineral assemblage is indicated by the emergence of magnetite as the increasing volumes of biotite and cordierite. Minor garnet and corundum are locally preserved, implying the mineral reaction 'g+cor→sp+sill' and more garnet and corundum in the peak stage. The garnet grains consist of 70%-72% almandine, 20%-22% pyrope, -4% grossularite and -4% spessartine. The XFe (Fe2+/(Fe2++Mg2+)) of representative garnet grains ranges from 0.77 to 0.80. The spinel exhibits an XFe range from 0.80 to 0.86. Different cordierite grains have similar compositions with Al of 3.89-3.93 a.p.f.u (atoms per formula unit) and XFe of 0.32-0.36. Biotite has high TiO2 (4.13%-5.23%) and Ti (0.23-0.30 a.p.f.u). K-feldspar grains consist of 78%-85% orthoclase, 15%-23% albite and -1% anorthite. Based on the mineral compositions and phase equilibrium modelling, the pressure-temperature (P-T) conditions of the major stage of mineral assemblage are constrained to 870-910 °C and 0.64-0.69 GPa, followed by later retrogression to 810-820°C and 0.49-0.53 GPa. A peak stage with higher P-T conditions (T>910 °C, P>0.69 GPa) can be inferred based on the relict peak minerals and characteristic mineral compositions (e.g. Ti in biotite). Zircon grains commonly show core-mantle-rim structures in cathodoluminescence (CL) images. The LA-ICP-MS zircon U-Pb dating analyses reveal a wide age range from 613±7 Ma to 877±9 Ma (except a maximum of 916±11 Ma) for the cores. The zircon bright rims yield a weighted mean age of 526±8 Ma with a wide range of Th/U (0.06-1.23), mostly higher than 0.1. [Conclusion] Based on the results, a few conclusions can be drawn: (1) The spinel-cordierite granulite recorded medium-low pressure/high-ultrahigh temperature metamorphism with a clockwise P-T evolution path and high dT/dP. (2) The results of zircon geochronological analysis show that zircon cores mainly record U-Pb ages in the range of 800--600 Ma, younger than typical ages of Grenvillian events, which may reflect younger inherited zircon cores or significant isotopic resetting. (3) The age of -530 Ma of zircon rims is interpreted to represent the post-peak cooling stage of the Pan-African tectono-thermal event. [Significance] This study examined the P-T conditions and the zircon ages of the spinel-cordierite granulite in the Mirror Peninsula. In combination with previous results, the P-T-t path constructed for the spinel-cordierite granulite provides new constraints on the evolution of the Prydz Bay belt during the Pan-African period. [ABSTRACT FROM AUTHOR]

The rapid progress of 6G mobile communication technologies has sparked a great deal research interests. The 6G core network architecture faces formidable challenges due to the escalating complexity of network service demands and diverse application scenarios. In response, our research endeavors to tackle these challenges by proposing a self-evolving architecture based on intelligent decision making. Inspired by the principles of biological morphological evolution, our architecture empowers the core network to dynamically adapt and reshape itself in order to effectively address the evolving communication environments. To facilitate this self-evolutionary process, we introduce a comprehensive framework encompassing mechanisms, architecture, agents, and algorithms that enable the network to autonomously generate and optimize its own structure, thereby ensuring adaptability to a wide range of application scenarios. By conducting concept proof simulation experiments, we have demonstrated the effectiveness of our self-evolution algorithm, which enables the 6G core network to make rational evolving decisions and exhibit remarkable adaptability to various application scenarios. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the chemokine and adhesion molecule profiles in aqueous humor (AH) of eyes with inactive uveitis and their correlations with inflammation relapse after cataract surgery. Methods: Patients with inactive uveitis who underwent cataract surgery between July 2014 and January 2016 at our center were included. Undiluted AH samples (100-120 µl) were obtained through lateral corneal incisions during surgery, and concentrations of monocyte chemoattractant protein 1 (MCP-1/CCL2), macrophage inflammatory protein 1 (MIP-1), interleukin 8 (IL-8), regulated on activation, normal T cell expressed and secreted (RANTES/CCL5), soluble vascular cell adhesion molecule (sVCAM) and soluble intercellular adhesion molecule (sICAM) were measured by cytometric bead array (BD Bioscience, San Jose, CA). AH levels of these inflammatory factors were compared between different uveitis entities and non-inflammatory control. Risk factors for postoperative inflammation relapse were also analysed in uveitic eyes. Results: As compared with the control group, the panuveitis group had significantly higher aqueous concentrations of MCP-1, IL-8, sVCAM, sICAM; the anterior uveitis group had significantly higher concentrations of MCP-1, MIP-1, sVCAM. Uveitic cataracts with postoperative inflammation relapse had significantly higher levels of MCP-1 and IL-8 in AH than those without. And multivariate cox regression analysis revealed that high AH levels of MCP-1 was an independent predictor for postoperative inflammation relapse. Conclusions: Clinically quiescent uveitic eyes have elevated levels of chemokines and soluble adhesion molecules in AH, of which MCP-1 is associate with inflammation relapses after cataract surgery. [ABSTRACT FROM AUTHOR]

Purpose: To address the visual prognosis and associated predictors of phacoemulsification and intraocular lens implantation in different uveitis entities in Han Chinese.Methods: A retrospective review of the uveitis patients who underwent phacoemulsification and intraocular lens implantation in our center between 2004 and 2014.Results: The 158 patients (226 eyes) included anterior uveitis (45 eyes), posterior/pan-uveitis (61 eyes), Vogt-Koyanagi-Harada disease (79 eyes) and Behçet disease (41 eyes). At 6 months after surgery, best-corrected visual acuity (BCVA) significantly improved (p < 0.001) in all uveitis groups with 134 (59.3%) eyes achieving 20/40 or better. The anterior uveitis and Behçet disease groups had significantly better and worse visual outcomes than other groups, respectively. Poor preoperative BCVA, macular lesions, and secondary glaucoma were independent variables that predicted a poor visual outcome.Conclusions: Our current study revealed a generally favorable outcome and associated predictors of phacoemulsification and intraocular lens implantation in uveitic cataracts in Han Chinese. [ABSTRACT FROM AUTHOR]

Purpose: To analyze the spectrum of uveitis at a tertiary hospital in northern China.Methods: This study is a retrospective study from June 2014 to February 2015. A total of 606 consecutive patients with uveitis were screened for etiologies and classified according to the anatomic sites of inflammation.Results: The mean age at presentation was 33.8 ± 15.5 years old. Males and females were almost equally affected. Panuveitis was the most common anatomic diagnosis, followed by anterior, posterior, and intermediate uveitis. VKH syndrome, Behçet disease and idiopathic anterior uveitis were the most common uveitis entities. Ocular complications were detected in 441 patients.Conclusions: More than half of the patients with uveitis from northern China had an identifiable cause or was diagnosed as a specific disease entity with VKH and BD among the major etiologies. Cataract, steroid-induced ocular hypertension and macular edema were the leading complications. [ABSTRACT FROM AUTHOR]

Objective: To study the relationship between the structure of macular central fovea and the best-corrected visual acuity (BCVA) during remission stage of Behcet's disease associated uveitis., Methods: Retrospective case series studies. The study covered 51 patients (79 eyes) during remission stage of Behcet's disease-associated uveitis from Peking Union Medical College Hospital in a three-year period from January 2012 to January 2015. There were 40 males, 11 females with the average age of 31.5 ± 6.9 years old (ranging from 18 to 46). All the patients received a complete set of ophthalmic examination, including BCVA, intraocular pressure, slit-lamp microscope, ophthalmoscope and frequency domain optical coherence tomography (OCT). All the eyes were divided into 4 groups according to central macular thickness (CMT) (the thick CMT group: CMT ≥ 130 µm; the thin CMT group: CMT < 130 µm) and the existence of ellipsoid zone. Group 1: thick CMT and ellipsoid (+); Group 2: thick CMT and ellipsoid (-); Group 3: thin CMT and ellipsoid (+); Group 4: thin CMT and ellipsoid (-). Sight disparity among multiple groups was tested with Kruskal Wallis, while the difference between two groups was tested with Mann-Whitney U test. Bonferroni correction was conducted when necessary., Results: The mean CMT was (151.4 ± 62.3) µm in all eyes (43 eyes in thick CMT group, 36 eyes in thin CMT group). According to grouping rule, there were 32 eyes in group 1, 11 eyes in group 2, 2 eyes in group 3 and 34 eyes in group 4. The BCVA of thick CMT group was better than that of thin CMT group (logMAR0.1 and logMAR1.0) (z = -6.88, P < 0.01). In addition, the BCVA of ellipsoid (+) group was better than the ellipsoid (-) group. (log MAR0.1 and log MAR1.0) (z = -6.60, P < 0.01)., Conclusion: Thick CMT and intact ellipsoid zone usually associated with relatively better BCVA in Behcet's disease-associated uveitis patients.

Objective: To observe the efficacy and safety of subconjunctival triamcinolone acetonide injections in the treatment of uveitic macular edema (UME)., Methods: A retrospective case series study. The clinical data of uveitis patients with macular edema were collected and analyzed at Peking Union Medical College Hospital from July 2009 to June 2014 with a minimum follow-up period of 6 months. The main outcome was central macular thickness (CMT) measured by optical coherence tomography at the 1st and the 3rd month after injection. The secondary outcomes included best corrected visual acuity (BCVA) at the 1st and the 3rd month, recurrence rate and intraocular pressure (IOP) within 6 months after injection., Results: Thirty two patients (37 eyes) were included in the study. At the 1st month after the first injection, 24 of the 37 eyes (64.9%) showed an obvious reduction of CMT (at least 20%), among them 15 eyes (40.5%) showed a total resolution. The mean CMT decreased from (498.9 ± 211.9) µm at baseline to (392.4 ± 232.3) µm (t = -4.070, P < 0.01). The BCVA improved in 20 eyes (54.1%) and 15 eyes (40.5%) gained more than 0.2 log MAR unit. The mean BCVA increased from logMAR, 0.45 ± 0.29 at baseline to logMAR, 0.33 ± 0.30 (t = -4.835, P < 0.01). No statistically significant difference was found in mean CMT or BCVA in 23 eyes between the 1st and the 3rd month after injection. These eyes didn't receive any additional medications for improvement of the condition. Seven eyes (30.4%, 7/23) got a second injection because of relapse within 6 months after the first injection and the efficacy was good. The elevation of IOP over 21 mmHg (1 mmHg = 0.133 kPa) were observed in 9 eyes and 3 eyes after the first and the second injection respectively. All of them were well controlled by either topical IOP lowering drugs or removal of the subconjunctival TA deposition., Conclusion: Subconjunctival injection of triamcinolone acetonide is an effective and safe method for uveitic macular edema.

Macular edema represents a major cause of visual loss in uveitis and its adequate management is crucial for the maintenance of useful vision in patients with uveitis. Corticosteroid is the first choice for UME treatment.Long term and sustained release implantation is the newest administration for medical therapy. The immunosuppressant such as cyclosporine, methotrexate, azathioprine and mycophenolate mofetil can be used specially for chronic and intractable UME. Moreover, these years, some newly developed biological agents, for example, anti-VEGF, interferon-α, anti-TNF and acetazolamide will provide new options for UME pharmacotherapy.