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The roles of Mn 2+ ions in the MnCO 3 compound, leading to the formation of an Mn 2+ -Yb 3+ dimer and affecting the gain coefficient for the 4 I 13/2 → 4 I 15/2 transition of Er 3+ ions and near-infrared (NIR) emission bandwidth flatness of Er 3+ /Tm 3+ /Yb 3+ co-doped in SiO 2 -ZnO-BaO (SZB) barium zinc silicate glasses, were investigated in this work. The composition of all elements from the original raw materials that exist in the host glasses was determined using energy-dispersive X-ray spectroscopy (EDS). Under the excitation of a 980 nm laser diode (LD), the NIR emission of Er 3+ /Tm 3+ /Yb 3+ -co-doped SZB glasses produced a bandwidth of about 430 nm covering the O, E, and C bands. The effects of Mn 2+ ions and the Mn 2+ -Yb 3+ dimer on the gain coefficient for the 4 I 13/2 → 4 I 15/2 transition of Er 3+ ions and bandwidth flatness of NIR emission of Er 3+ /Tm 3+ -co-doped and Er 3+ /Tm 3+ /Yb 3+ -co-doped SZB glasses were also assigned. The optimal molar concentration of Mn 2+ ions was determined such that the NIR bandwidth flatness of Er 3+ /Tm 3+ /Yb 3+ -co-doped SZB glasses was the flattest. In addition, the role of Mn 2+ ions in reducing the gain coefficient for the 4 I 13/2 → 4 I 15/2 transition of Er 3+ ions was also calculated and discussed., Competing Interests: There are no conflicts of interest to declare., (This journal is © The Royal Society of Chemistry.)

Having carried out four cases of vaginal caesarean section the authors describe the technique they used. The advantages of the operation are: it is simple and can be carried out quickly, future obstetric behaviour is not compromised. It is important to avoid two complications of the operation: haemorrhage and injury to the bladder. These are reduced if the vertical incision in the cervix is made in the midline and long enough. The ideal indications for the operation are absence of cervical dilatation, or the occurrence of severe maternal haemorrhage during the operation to terminate a pregnancy, or while the uterine contents are being expelled towards the end of the second trimester. It is disputable whether there is a place for vaginal caesarean operation when the fetus is alive, in view of the recent studies on fetal prognosis.

A retrospective study of 70 fat women and 70 women of normal weight was carried out to compare their obstetric performance. The patients were assessed before pregnancy for corpulence by estimating the body mass index (IMC). Obesity was defined by having an index of 30 or above. The mean weight of the obese patients at delivery was 142 kgs and of the controls 65.4 kgs. The main risk in obese patients is a raised blood pressure (34%); and in spite of this no child showed intrauterine growth retardation. The mean weight of the newborn infants was 3.7 kgs against a mean weight of 3.2 kgs in the control group. Eighteen infants born to obese mothers were very heavy (25%). The increase in fetal weight explains why the caesarean section rate was three times as high in the obese patients as in the control due to disproportion (25%). These differences are statistically significant. Neonatal morbidity was similar in the two groups. It is debatable whether a slimming diet was worthwhile. All the same calorie intake reduced slightly to about 1.800 calories a day together with vitamin supplements is advisable. It does not have any ill effect on the fetus.

Forty-five patients who had primary cancer of the breast had a laparotomy when a second cancer appeared in the ovaries. There were no other peritoneal metastases to suggest that it was disseminated breast cancer. Twenty-eight had primary ovarian cancer and 17 metastases from breast cancer. The study comparing the two groups shows that: there are few clinical or paraclinical features that make it possible to arrive at a differential diagnosis; ovarian metastases occurring in patients who have primary breast cancer carry a more serious prognosis; if the cancer is a primary ovarian cancer (and not a secondary) the chances of survival are less poor; in primary ovarian cancer the results justify our attitude for carrying out surgery; screening systematically for ovarian involvement by using CA 125 or by routine ultrasound does not seem to us to be effective.