A regioselectively 1,1',3,3'-tetrazincated ferrocene complex displaying core and peripheral reactivity.

Regioselective 1,1',3,3'-tetrazincation [C-H to C-Zn(Bu)] of ferrocene has been achieved by reaction of a fourfold excess of di--butylzinc (BuZn) with sodium 2,2,6,6-tetramethylpiperidide (NaTMP) in hexane solution manifested in the trimetallic iron-sodium-zinc complex [Na(TMP)Zn(Bu){(CH)Fe}], . X-ray crystallographic studies supported by DFT modelling reveal the structure to be an open inverse crown in which two [Na(TMP)Zn(Bu)Na(TMP)Zn(Bu)] cationic units surround a {(CH)Fe} tetraanion. Detailed CD NMR studies have assigned the plethora of H and C chemical shifts of this complex.

Development of gas chromatography-mass spectrometry (GC-MS) and other rapid screening methods for the analysis of 16 'legal high' cathinone derivatives.

The prevalence of so-called 'legal high' drugs in forensic science drug casework has increased markedly in recent years. This has given rise to both legal and analytical challenges in the identification of these substances. The requirement for validated, reliable and rapid testing methodologies for these compounds is obvious.

Concealed cyclotrimeric polymorph of lithium 2,2,6,6-tetramethylpiperidide unconcealed: X-ray crystallographic and NMR spectroscopic studies.

Lithium 2,2,6,6-tetramethylpiperidide (LiTMP), one of the most important polar organometallic reagents both in its own right and as a key component of ate compositions, has long been known for its classic cyclotetrameric (LiTMP)4 solid-state structure. Made by a new approach through transmetalation of Zn(TMP)2 with tBuLi in n-hexane solution, a crystalline polymorph of LiTMP has been uncovered. X-ray crystallographic studies at 123(2) K revealed this polymorph crystallises in the hexagonal space group P63 /m and exhibited a discrete cyclotrimeric (C3h ) structure with a strictly planar (LiN)3 ring containing three symmetrically equivalent TMP chair-shaped ligands.

Milk flow rates can be used to identify and investigate milk ejection in women expressing breast milk using an electric breast pump.

Currently there is no simple method available to assess milk ejection and breast milk flow in lactating women in both the clinical and research setting. The authors hypothesize that changes in milk flow rate are associated with milk ejection and therefore may provide a method suitable for the assessment of milk ejection and removal. Mothers (n = 23) expressed milk from one breast for a 15-minute period using both weak and strong vacuums on two to four separate occasions using an experimental electric breast pump (Medela AG, Baar, Switzerland).

Volume and frequency of breastfeedings and fat content of breast milk throughout the day.

Objective: We aimed to provide information that can be used as a guide to clinicians when advising breastfeeding mothers on normal lactation with regard to the frequency and volume of breastfeedings and the fat content of breast milk.

Methods: Mothers (71) of infants who were 1 to 6 months of age and exclusively breastfeeding on demand test-weighed their infants before and after every breastfeeding from each breast for 24 to 26 hours and collected small milk samples from each breast each time the infant was weighed.

Results: Infants breastfed 11 +/- 3 times in 24 hours (range: 6-18), and a breastfeeding was 76.

The use of ultrasound to characterize milk ejection in women using an electric breast pump.

This study aimed to use ultrasound imaging to investigate the milk ejection characteristics of women during a 10-minute expression using an electric breast pump capable of applying 2 markedly different vacuum patterns. The classic pattern (47 cycles/min) and 3-phase pattern (pre-milk ejection: 120 cycles/min, post-milk ejection: 20 cycles/min for 2 minutes post-milk ejection then 55-78 cycles/min for 8 minutes) were tested, and the milk expressed was collected in 30-second intervals. Multiple milk ejections (96%) were detected (classic: 3.

Ultrasound imaging of milk ejection in the breast of lactating women.

Objective: Currently, the methods for assessing milk ejection in women include serial sampling of plasma oxytocin and measurement of intraductal pressure, both of which are invasive and may induce stress. We hypothesized that milk ejection would cause an increase in milk-duct diameter that could be observed noninvasively with ultrasound, and this could be used to investigate the physiology of milk ejection in women.

Methods: One milk duct was scanned in the unsuckled breast in 2 groups of mothers: group BB (n = 21) for the beginning of a breastfeed and group EB (n = 24) for the entire breastfeed.

Response of breasts to different stimulation patterns of an electric breast pump.

To test the effect on milk ejection, an electric breast pump was programmed to provide pumping patterns with frequencies of 45 to 125 cycles/min and vacuums of 45 to -273 mm Hg. The time taken for milk ejection to occur (measured using ultrasound to detect a dilation of a lactiferous duct in the opposite breast) in response to the current Medela electric breast pump pattern (45 cycles/min) was 147 +/- 13 s. For patterns that more closely resemble the sucking frequency of an infant when it first attaches to the breast, milk ejection occurred between 136 +/- 12 and 104 +/- 10 s, although this difference was not statistically significant.