Synthesis and characterization of TiFe(0.7-x)Mn(0.3)V(x) (x = 0.05, and 0.1) and Ti(1-y)Ta(y)Fe(0.7)Mn(0.3) (y = 0.2, and 0.4) nanostructured metal hydrides for low temperature applications.

Metal hydrides (MH) are often preferred to absorb and desorb hydrogen at ambient temperature and pressure with a high volumetric density. These hydrogen storage alloys create promising prospects for hydrogen storage and can solve the energetic and environmental issues. In the present research work, the goal of our studies is to find the influence of partial substitution of small amounts of vanadium and tantalum on the hydrogenation properties of TiFe(0.7-x)Mn(0.3)V(x) (x = 0.05, and 0.1) and Ti(1-y)Ta(y)Fe(0.7)Mn(0.3) (y = 0.2, and 0.4) alloys, respectively. The nominal compositions of these materials are TiFe(0.6)Mn(0.3)V(0.05), TiFe(0.6)Mn(0.3)V(0.1), Ti(0.8)Ta(0.2)Fe(0.7)Mn(0.3), and Ti(0.6)Ta(0.4)Fe(0.7)Mn(0.3). All samples were synthesized by arc-melting high purity elements under argon atmosphere. The structural and microstructural properties of the samples were studied by using XRD and SEM, respectively, while the corresponding microchemistry was determined by obtaining EDS measurements at specific regions of the samples. Mapping was obtained in order to investigate atomic distribution in microstructure. Moreover, to ensure the associations between the properties and structure, all samples were examined by an optical microscope for accessional characterization. From all these microscopic examinations a variety of photomicrographs were taken with different magnifications. The hydrogenation properties were obtained by using a Magnetic Suspension Balance (Rubotherm). In this equipment, the hydrogen desorption and re-absorption, can be investigated at constant hydrogen pressures in the range of 1 to 20 MPa (flow-through mode). At least 3.43 wt.% of absorbed hydrogen amount was measured while the effect of substitutions was investigated at the same temperature.

Association of single umbilical artery with congenital malformations of vascular etiology.

The possible association of a single umbilical artery (SUA) with malformations of vascular etiology is investigated in this study. Four hundred twelve fetal and embryonic autopsies showing one or more congenital malformations, collected over 7 years, were reviewed. Microscopic confirmation of a SUA was evident in 20 cases (4.85%). The two subgroups with 2 (nA = 20) or 3 umbilical vessels (nB = 392) were compared with each other, in relation to the frequency of malformations per organ system. In the group of fetuses with congenital malformations, no association was observed between SUA and the incidence of CNS, cardiac, pulmonary, or genital malformations. However, there was a significantly higher incidence of atresia of hollow organs (P = 0.003), renal aplasia (P = 0.034), and limb reduction defects (LRD) (P = 0.0383) when only a single umbilical artery was present. This suggests a possible etiopathogenetic association of SUA with congenital malformations of vascular etiology. Furthermore, the findings of our study suggest that prenatal identification of a SUA warrants a thorough search for atresias, renal aplasia, and LRD-type malformations.

Prenatal ultrasonographic detection of the tracheal atresia sequence.

We report a rare case of tracheal atresia, without fistula, in a 19 weeks' female fetus. The abnormality was detected by prenatal ultrasonography, which demonstrated a bilateral and uniform hyperechogenicity and enlargement of the lungs, associated with ascites and moderate oligohydramnios. We suggest that oligohydramnios may be helpful in distinguishing the upper respiratory tract obstruction from congenital cystic adenomatoid malformation of the lungs, type III. A morphometric study revealed a three-fold more dense pulmonary vasculature in comparison with two control cases of the same gestational age. The pathological finding of pulmonary and vascular hyperplasia as well as the pathophysiology of the syndrome are discussed.

Intrafetal prostaglandin F2alpha administration for uterine evacuation in a case of intrauterine death.

An original route of prostaglandin F2alpha administration for uterine evacuation in a case of a midtrimester intrauterine death is presented. The ultrasonographic study revealed a hydropic fetus with a massive nuchal cystic hygroma and oligohydramnios. Given our previous experience with intrafetal prostaglandin administration in a similar case but with a living fetus, we injected prostaglandin F2alpha into the nuchal cysts under continuous ultrasonographic guidance in order to induce uterine evacuation. The pregnancy was successfully terminated 16 h later.

Low beta-hCG is associated with poor prognosis in association with an embryo with positive cardiac activity.

Seven pregnancies with positive fetal heart activity and low or very low serum beta-human chorionic gonadotropin (beta-hCG) levels were investigated. The gestational age by dates was between 6 weeks 3 days and 8 weeks 4 days at the time of the first ultrasound scan and beta-hCG ranged between 282 and 10,000 mIU/ml of the Second International Standard. The crown-rump lengths ranged between 6 and 13 mm and heart activity was always detected. Four cases were scanned because beta-hCG was lower than that expected for the gestational age; in these cases the yolk sac was present but the gestational sacs were small, with a trophoblastic ring that looked thin and subjectively seemed abnormal. The beta-hCG level was measured in the other three cases, because the gestational sacs were small and had a thin trophoblastic ring. In these cases, fetal heart activity was clearly imaged. All cases were scheduled for a repeat ultrasound scan 2 weeks later. Three cases aborted spontaneously the following week, whereas in the other four no heart activity was detected in a repeat sonogram 2 weeks later. Low serum beta-hCG levels indicate a poor prognosis even when associated with an embryo with positive cardiac activity detected ultrasonographically.

Intrafetal prostaglandin F2 alpha administration for midtrimester pregnancy termination: a case report.

An original route for prostaglandin F2 alpha administration for midtrimester pregnancy termination is presented. The diagnosis of nuchal cystic hygroma in a hydropic fetus with severe oligohydramnios was made by real-time ultrasonography. Forty milliliters of fluid was aspirated for laboratory studies and prostaglandin F2 alpha was injected into the nuchal cysts to induce abortion. The pregnancy was successfully terminated 8 hours later.

PIP: Although the use of prostaglandins (PGs) in 2nd-trimester abortions is well established, less clear is the optimal route of administration. The literature includes reports of intra- and extraamniotic, intracervical, intravaginal, intravenous, intramuscular, and oral administration. This article describes a case in which PG F-2-alpha was injected into the nuchal cysts of a fetus with cystic hygroma, edema anasarca, and oligohydramnios. Nuchal cystic hygroma, a congenital malformation of the lymphatic system involving a jugular lymphatic obstruction sequence, was diagnosed in the 27-year-old patient by real- time ultrasonography performed at 21 weeks' gestation. Since there was no pouch of amniotic fluid, intraamniotic PG instillation was not an option. However, the severe cystic hygroma and hydrops offered an alternative site for PG instillation. During the abortion procedure, 40 ml of fluid contained in the cysts was aspirated for laboratory studies and 40 mg of PG F-2-alpha was injected under ultrasonographic guidance. Uterine contractions began 2 hours later and the injection-abortion interval was 8 hours. The administration of meperidine and atropine sulfate to prevent pain and PG-associated side effects was effective. This successful outcome in this case suggests a need for further investigation of intrafetal PG administration.