Purpose -The thixotropy of lubricating grease thickened with lithium 12-hydroxystearate with mineral base oil was investigated. The thixotropy has a significant influence on the flow resistance and pressure drop in the structural components of lubrication systems, which is of major importance as today the latter are being centralized and automated. The paper aims to discuss these issues. Design/methodology/approach -Rheometer studies on thixotropy were carried out and the grease microstructure was visualized using atomic force microscopy (AFM). Total reflection Fourier transform infrared spectroscopy (ATR-FTIR) was used to study the physicochemical interactions which indicate the disintegration and recovery of the grease microstructure. Findings -A qualitative assessment of the physicochemical interactions between lithium soap floccules was made and a theory of the self-ordering effect of lithium 12-hydroxystearate associated molecules during shearing and their aggregation and flocculation during relaxation has been proposed. Originality/value -Because of the complexity of the disintegration and recovery of the lubricating grease thickener microstructure, there is still limited physical understanding of the mechanism of this process. Therefore, the present research was undertaken to identify the phenomena involved.

Introduction and objectiveUterine artery embolization (UAE) is a minimally invasive treatment option for symptomatic fibroids. Long-term follow-up studies have shown that at five-year follow-up after UAE, up to 30% of patients required a hysterectomy. Therefore, it seems of utmost importance to identify patients, who are unlikely to benefit from UAE. It has been postulated that the percentage volume reduction of fibroids may predict long-term UAE outcome. The results of available studies are equivocal, therefore it seemed of interest to investigate the correlation between the preinterventional intramural fibroid volume and imaging outcome of UAE in premenopausal patients.Material and methodsUterine artery embolization was performed in 65 premenopausal patients with symptomatic, intramural fibroids. Dominant fibroid volume was assessed using an integrated VOCAL (Virtual Organ Computer-aided AnaLysis) imaging program at baseline and 3 months after UAE. The percentage reduction of fibroid volume was calculated. The association between preinterventional fibroid volumes and percentage volume reductions was determined with the Spearman rank correlation test.ResultsBefore UAE, the median dominant fibroid volume was 101 cm3 (range 23.6-610). At three-month follow-up the median dominant leiomyoma volume decreased to 50.4 cm3 (range 6.9-193.9). Median percentage reduction of fibroid volume three months after UAE was calculated at 50.1% (range 2.7-93.5). The Spearman correlation test between the preinterventional dominant fibroid volume and percentage volume reduction showed a statistically significant, positive correlation (R = 0.33; p = 0.006).ConclusionsThe percentage volume reduction of intramural leiomyomas after UAE seems to be more pronounced in the case of larger tumors.

Uterine fibroids (also known as leiomyomas or myomas) are the most common benign tumors affecting reproductive organs in women. They are monoclonal tumors of the uterine smooth muscle, which spring from myometrium. It is estimated that they occur in 50-60% of the female population and rise to 70% by the age of 50. While mostly asymptomatic, myomas can be connected with several conditions, including abnormal bleeding with subsequent anemia, pelvic masses, pelvic pain, bulk symptoms, unfavorable impact on fertility and obstetric complications. Factors, which predispose the emergence of fibroids are: hormones, Afro-American ethnicity, age, obesity, adverse pregnancy outcome history, early menarche, genetic factors, alcohol, caffeine or eating too much red meat. On the other hand, there are factors, which can decrease this risk: pregnancy, early menopause and tobacco smoking. There are several mechanisms of fertility impairment in females with fibroids: alternations in uterus function (flawed blood supply, increased contractility), changes in the normal uterus anatomy, local hormonal changes induced by fibroids. In this review the connection between fibroids and infertility is analyzed.

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