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In this paper, the effect of binder decay rather than a change in the pigments on the blurring of ancient wall paintings was researched. The simulated wall paintings were prepared by brushing an aqueous solution containing gelatine and ochre grains on the surface of cylindrical compressed soil samples. Then, the dried samples were calcined at 650 °C for 2 h to obtain the simulated wall paintings with the degraded binder gelatine. Next, the calcined samples were brushed with a certain amount of acetone solution containing an ionic liquid ([BMIm]PF6) to obtain the corresponding repaired samples. Based on the results from various characterization methods (UV–vis, FTIR, XRD, XPS, SEM, TG), the following conclusions were drawn. The degradation of the binder caused by calcination increases the surface roughness of the painting layer, resulting in enhanced scattering. In this case, because scattering decrease the light absorption by the pigments, even if unchanged pigment exists in the painting layer, its colour can become blurred. The filling of the ionic liquid into the pores caused by gelatine decay in the painting layer can decrease the scattering, and the blurred colour can be restored to some extent. As typical examples, this principle was successfully applied to restore the blurred colour of an ancient Chinese wall painting (Tang Dynasty) and a pottery (Eastern Han Dynasty).

Constructing methods for cleaning stains on paper artworks that meet the requirements of preservation of cultural relics are still challenging. In response to this problem, a novel electrochemical cleaning method and the preparation of corresponding electrodes were proposed. For this purpose, the conductive graphene (rGO)/polyacryamide (PAM)/montmorillonite (MMT) composite hydrogel as cathode and PbO2-based material as anode were prepared and characterized. The electrochemical cleaning efficiencies of real sample and mimicking paper artifacts were evaluated, and the effects of the electrochemical cleaning on paper itself were detected. Based on the above experiments, the following results were obtained. The composite hydrogel with attractive mechanical properties is mainly based on the hydrogen bond interactions between PAM chains and MMT. The results of cleaning efficiency revealed that the black mildew stains together with the yellowish foxing stains were almost completely eliminated within 6 min at 8 mA/cm2, and various stains formed by tideline, foxing, organic dyes and drinks could be thoroughly removed at 4 mA/cm2 within 5 min. In addition, the proposed cleaning method has advantages in local selectivity, easy control of cleaning course, and reusability, which represents a potential utility of this approach.

This study aimed to evaluate the validation of the leptin receptor-deficient mice model for secondary osteoporosis associated with type 2 diabetes mellitus (T2DM) at bone micro-architectural level. Thirty three 36-week old male mice were divided into four groups: normal control (db/m) (n = 7), leptin receptor-deficient T2DM (db/db) (n = 8), human C-reactive protein (CRP) transgenic normal control (crp/db/m) (n = 7) and human CRP transgenic T2DM (crp/db/db) (n = 11). Lumber vertebrae (L5) and bilateral lower limbs were scanned by micro-CT to analyze trabecular and cortical bone quality. Right femora were used for three-point bending to analyze the mechanical properties. Trabecular bone quality at L5 was better in db/db or crp/db/db group in terms of bone mineral density (BMD), bone volume fraction, connectivity density, trabecular number and separation (all p crp/db/db group was significantly shorter than db/m group (p db/db and crp/db/db groups (p > 0.05). Maximum loading and energy yield in mechanical test were similar among groups while the elastic modulus in db/db and crp/db/db significantly lower than db/m. The leptin-receptor mice is not a proper model for secondary osteoporosis associated with T2DM.

We investigated the systemic effect of sclerostin monoclonal antibody (Scl-Ab) treatment on intact non-operated bones in an open osteotomy male Sprague Dawley (SD) rat model. Six-month-old male SD rats were subjected to transverse osteotomy at the right femur mid-shaft. Rats were injected subcutaneously with vehicle or Scl-Ab (25 mg/kg, 2 times per week) treatment for 9 weeks. Compared with vehicle control, Scl-Ab treatment significantly improved trabecular and cortical bone mass and microarchitecture at L5 vertebrae and left femora by micro-CT at week 6 and 9. Mechanical testing showed that Scl-Ab treatment resulted in significantly higher stiffness, energy to failure and ultimate load at the femora at week 9. Mineral apposition rate, mineralizing surface and bone formation rate on the trabecular bone in the distal femora was significantly increased in Scl-Ab group at week 6 and 9. The administered Scl-Ab was localized in the osteocytes and beta-catenin was strongly expressed in osteoblasts. Scl-Ab treatment significantly increased serum P1NP level and there was no between-group difference in serum level of CTX-1. In conclusion, Scl-Ab treatment could induce rapid and sustained increase in bone formation, bone mass and bone strength in non-operated bones. Sclerostin inhibition might be advantageous to prevent secondary fracture(s).