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Objective: Additional risk factors for preterm delivery in pregnant women with cervical shortening are not fully understood; however, mid-trimester cervical shortening is accepted as a risk factor for preterm delivery. This study aimed to identify risk factors associated with subsequent preterm delivery among patients with short cervix detected after late mid-trimester. Materials and methods: This was a retrospective study of medical data from a single perinatal tertiary facility. We identified 134 asymptomatic women with singleton pregnancies where cervical shortening (≤25 mm) was detected during routine universal screening at 22–33 weeks. Statistical analyses were conducted to identify causal relationships between the incidence of preterm delivery and known risk factors for preterm delivery. Results: Incidence of preterm delivery was 27.6% (37/134) and preterm premature rupture of membrane was preceded in 46.0% (17/37) of the women with preterm delivery. Using logistic regression analysis, we identified uterine contractions [aOR 4.25, 95% confidence intervals (CI):1.68–12.1] and increased C-reactive protein (CRP) and increased white blood cell (WBC) in blood test (CRP: aOR 3.45, 95% CI:1.50–9.71; WBC: aOR 1.28, 95% CI: 1.08–1.55) as risk factors which significantly increased the risk of preterm delivery among women diagnosed with short cervix. Preterm delivery occurred in 91% of women positive for both uterine contractions and CRP >0.5 mg/dl. Conclusions: Uterine contraction and elevated CRP were additional risk factors for preterm delivery among women with short cervix. These results might be clinically useful to evaluate subsequent risk for preterm delivery in asymptomatic pregnant women presenting with short cervix in mid-pregnancy. Keywords: Preterm labor, Cervical length, Inflammation, Pregnancy

The hydrogen absorption properties of the Sm2Fe17 alloy were investigated by measurements of pressure–composition isotherms over the temperature range 423–623 K. The hydrogen atoms occupy not only the octahedral 9e sites but also the tetrahedral 18g sites in the rhombohedral Sm2Fe17 lattice. It is believed that the full occupation of the 9e sites, corresponding to the hydrogen composition H/Sm2Fe17=3.0, is followed by a partial occupation of the 18g sites. In the present work, however, the partial molar entropy of hydrogen suggests that the 18g sites start to be occupied even at low hydrogen concentrations. This behavior is followed by drastic changes in the partial thermodynamic properties of hydrogen starting around H/Sm2Fe17=2.0, implying that a large amount of hydrogen can start to enter the 18g sites before the 9e sites are completely occupied. This thermodynamic behavior was confirmed by discontinuous changes in the lattice constants and the saturation magnetization of Sm2Fe17 alloy with hydrogen composition.

Photo-induced deposition of aluminum films on silicon dioxide and on a hydrogen terminated silicon surface was carried out using dimethylaluminum hydride (DMAH) and a deuterium lamp. After an initial nucleation was induced by irradiation, film growth was sustained without irradiation at a substrate temperature of 200°C where no deposition can occur via a thermal reaction alone. In addition, the growth rate decreased under irradiation during the growth period. An ArF laser also induced a similar photoinitiation effect.

Photo-induced effects on nucleation were compared on various surfaces during chemical vapor deposition of Al thin films, using dimethylaluminum hydride. The emission around 160 nm from a deuterium lamp was more effective for nucleation on a H-terminated Si surface than the emission around 240 nm. The catalytic reaction of a Ti layer for nucleation was promoted by irradiation, while the UV light suppressed nucleation on a Pd layer.