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Functional connectivity of the primary visual cortex was explored with resting functional magnetic resonance imaging among adults with strabismus and amblyopia and healthy controls. We used the two-sample test and receiver operating characteristic curves to investigate the differences in mean functional connectivity values between the groups with strabismus and amblyopia and healthy controls. Compared with healthy controls, functional connectivity values in the left Brodmann areas 17, including bilateral lingual/angular gyri, were reduced in groups with strabismus and amblyopia. Moreover, functional connectivity values in the right Brodmann area 17, including left cuneus, right inferior occipital gyrus, and left inferior parietal lobule, were reduced in adults with strabismus and amblyopia. Our findings indicate that functional connectivity abnormalities exist between the primary visual cortex and other regions. This may be the basis of the pathological mechanism of visual dysfunction and stereovision disorders in adults with strabismus and amblyopia.

Theoretical ternary phase diagrams with good agreement with experiment cloud point data were constructed for a btda-tdi/mdi (p84) co-polyimide/N-methyl-2-pyrrolidinone (NMP)/water system. The theoretical phase diagram was calculated based on the Flory–Huggins theory of polymer solution. To construct the theoretical phase diagrams, all the binary interaction parameters were determined accurately. The water–P84 co-polyimide interaction parameter (χ13) and the nmp-p84 co-polyimide interaction parameter (χ23) were calculated from solubility parameters theoretically and determined by equilibrium swelling experiment and intrinsic viscosity measurement, respectively. The water–NMP interaction parameter ( g12) was calculated by the universe sichemical functional group activity coefficient method. According to the theoretical binodals, spinodals and critical points of the p84 co-polyimide/nmp/water system at different temperatures, we conclude that the effect of temperature on the position of binodal curves was small; this phenomenon is similar to the results of the cloud point titration experiment at different temperatures. The study also found that the p84 co-polyimide fractions of both theoretical critical points and experimental critical points are lower (less than 4 wt%), that is, the spinning or coating solution will be demixed by nucleation and the growth mechanism at the early stage of the forming process.

Poly(m-phenylene isophthalamide) (PMIA) fibre is a kind of aromatic polyamide fibre, which can be prepared by a wet-spinning method. In this work, the process conditions of spinning influenced the performance and structure of the coloured PMIA fibre, and these conditions included spinning speed, coagulation bath, etc. Because the diffusion coefficient was associated with the performance and structure, the ratio of solvent to coagulant could explain the reason of influence of the coagulation bath on the fibre. In this study, PMIA spinning dopes with Colour Inde Blue 60 were first commixed in a pressurizer and then spun into a coagulation bath under a pressure of around 0.3 MPa. At a coagulation bath temperature of 50 °C, pure or dope-dyed PMIA fibres were prepared by wet spinning, and then the spun fibres were extracted by an ultrasonic oscillation method. The effect of the jet stretch ratio and the temperature and concentration of coagulation bath on the ratio of diffusion coefficient of solvent to coagulator were analysed during spinning process of dope-dyed PMIA fibres. The properties and structures of coloured PMIA fibres were characterized by SEM. Finally the optimized spinning technology of the dope-dyed PMIA fibre was obtained.

PurposeTo investigate spontaneous brain activity in patients with dry eye (DE) and healthy control (HC) using the fractional amplitude of low frequency fluctuation (fALFF) technique with the aim of elucidating the relationship between the clinical symptoms of DE and changes in brain function.Material and MethodsA total of 28 patients with DE and 28 matched healthy volunteers (10 males and 18 females in each group) were enrolled. Resting-state functional magnetic resonance imaging scans were performed in both groups. Then all subjects were required to complete a comprehensive Hospital Anxiety and Depression Scale (HADS). Receiver operating characteristic (ROC) curve analysis was used to evaluate the differences in fALFF values between the two groups and their diagnostic value. Linear correlations between HADS and fALFF values in different brain regions of DE patients were analyzed using the Pearson correlation coefficient.ResultsPatients with DE had significantly higher fALFF values in the left calcarine sulcus (CS) than the HC group, while fALFF values in the bilateral middle frontal gyrus (MFG) and right MFG/right inferior frontal gyrus (IFG) were significantly lower in DE patients than in HC group. fALFF values had a high diagnostic value for differentiating patients with DE from the HC group (P < 0.001). Right MFG and right MFG/IFG were significantly correlated with HADS values.ConclusionOur study found that DE mainly involved functional disorders in the brain areas of the left CS, bilateral MFG and right MFG/right IFG, which helped us to find possible clinical features of DE disease and reflected the potential pathological mechanism of DE.