Correction: Azamacrocycles and tertiary amines can be used to form size tuneable hollow structures or monodisperse oxide nanoparticles depending on the 'M' source.

Correction for 'Azamacrocycles and tertiary amines can be used to form size tuneable hollow structures or monodisperse oxide nanoparticles depending on the 'M' source' by Graham E. Tilburey, et al., Dalton Trans., 2019, 48, 15470-15479.

Azamacrocycles and tertiary amines can be used to form size tuneable hollow structures or monodisperse oxide nanoparticles depending on the 'M' source.

We show that the azamacrocycle 'cyclam' (1,4,8,11-tetraazacyclodecane) in conjunction with a silicon catecholate ion generates novel hollow tetragonal tube-like crystalline materials [(C6H4O2)3Si][C10H26N4]·H2O, whose dimensions can be tuned according to the pH of the reaction medium. The synthesis approach was successful for both silicon and germanium and we hypothesise that a range of other catecholate precursors of elements such as iron could be used to generate a large array of inorganic materials with interesting morphologies. The synthesis approach can be extended to tertiary diamines with functional group spacing playing an important role in the efficacy of complexation. Of the molecules explored to date, a C2 spacing (N,N,N',N'-tetramethylethylenediamine (4MEDAE)), leads to the most efficient structure control with hollow hexagonal tube-like structures being formed. In addition, we show that azamacrocycles, in the presence of unbuffered tetramethoxysilane (TMOS) solutions can be used to manipulate silica formation and provide a fast (ca. 10 minutes) synthesis route to particles whose diameter can be tuned from ca. 20 nm to several hundreds of nm under reaction conditions (no extremes of pH) that make the sols suitable for direct use in biotechnological applications.

Quantifying dyspigmentation in facial skin ageing: an explorative study.

OBJECTIVE: The skin melanin system is affected by ageing, resulting in dyspigmentation with associated clinical and psychosocial consequences. In dark skinned phenotypes, broad evidence is available, whereas little is known about pigmentary changes in fair-skinned Caucasians. The objective of this study was to investigate age-related changes in facial pigmentation and dyspigmentation in subjects of skin phototypes II-III and to develop and test parameters for quantifying dyspigmentation. METHODS: Twenty-four skin healthy female subjects were recruited in three distinct age groups (30-40, 50-60, 70-80 years). Skin colour was measured by Mexameter and Chromameter. Skin dyspigmentation was measured by clinical evaluation and newly developed image-processing parameters on the cheeks and the forehead. The reliability of the clinical evaluation was investigated by intraclass correlation coefficients between three raters, and the validity of the dyspigmentation parameters was analysed by bivariate correlations with related measures. RESULTS: Skin lightness decreased with increasing age. Clinical dyspigmentation scores showed positive associations with chronological age ranging between 0.452 and 0.606. RBX(®) -Brown transformation-based hyperpigmentation and hypopigmentation indices increased with age, whereas the overall pigmentation intensity decreased with age at the cheeks. The image analysis-based parameters showed strong associations with the clinical scores and related measurements. CONCLUSION: We demonstrated age-related changes in the facial colour and dyspigmentation of fair-skinned Caucasian females. An increase in dyspigmentation was found by clinical scoring and the RBX(®) -Brown transformation-based pigmentation indices. The validity of hyper- and hypopigmentation indices and overall pigmentation intensity was supported. The RBX(®) transformation-based pigmentation indices might be applied in future studies to complement or substitute clinical evaluation.