Twin Pregnancy in a Woman with Uterus Didelphys

Uterus didelphys is one of the congenital uterine anomalies due to defective medial fusion of mullerian ducts. This anomaly is known to have poor reproductive outcome and women with this condition often have to be treated for infertility. Multiple gestation is rare with this condition. An 18 years old primigravida presenting with threatened abortion at eight weeks, was found to have uterus didelphys. She was managed conservatively, aborted one of the fetuses at 16weeks of gestation, and went till term to deliver a healthy baby by cesarean section

Response to “Comment on ‘Electrically injected spin-polarized vertical-cavity surface-emitting laser’ ” [Appl. Phys. Lett. 88, 056101 (2006)]

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/87776/2/056102_1.pd

Differential gain in InP‐based strained layer multiple quantum well lasers

Compressive biaxial strain has been predicted to enhance the small‐signal modulation bandwidth of quantum well lasers, owing to increased differential gain in these devices. However, the effect of tensile strain on these devices is less clear. We have investigated the effects of both compressive and tensile strain on the differential gain for multiple quantum well lasers with InxGa1−xAs quantum wells for 0.33≤x≤0.73. We observe markedly increased differential gain for both compressive and tensile strain, indicating that large modulation bandwidths can be obtained in both cases.  Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/69822/2/APPLAB-61-18-2129-1.pd

Donor‐doping characteristics of gas‐source molecular beam epitaxial Si and Si1−xGex using phosphine

Well‐behaved and reproducible n‐type doping of Si and Si1−xGex by phosphine during gas‐source molecular beam epitaxy is demonstrated. No significant reduction of growth rate of these materials in the presence of phosphine is recorded in the doping range of 1017–1019 cm−3 and perfect surface morphologies are observed. The incorporated P atoms are fully activated without ex situ annealing. The doping profiles are well defined in both Si and Si1−xGex layers. A p‐Si0.9Ge0.1/n‐Si heterojunction diode made with boron and phosphine doping has demonstrated excellent rectifying characteristics.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/69914/2/JAPIAU-76-4-2213-1.pd

Monolithic single GaN nanowire laser with photonic crystal microcavity on silicon

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/98667/1/ApplPhysLett_98_021110.pd

Determination of critical layer thickness and strain tensor in InxGa1−xAs/GaAs quantum‐well structures by x‐ray diffraction

We have used the double‐crystal x‐ray rocking curve technique to determine lattice constant, strain relaxation, thickness, and critical thickness of a thin InxGa1−xAs layer embedded in GaAs. In this work we have measured and analyzed x‐ray data over a wide scan angle (∼2.0°). This allows the simultaneous determination of buried layer thickness and strain. The measurement results were analyzed by the dynamical diffraction theory. The critical thickness for an InGaAs layer embedded in GaAs obtained from x‐ray data is shown to be larger than that predicted by the force balance model. The strain tensors as a function of layer thickness are also analyzed for the buried InxGa1−xAs of different x values.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/71348/2/JAPIAU-73-11-7389-1.pd

Impact ionization coefficients for electrons and holes in strained In0.2Ga0.8As and In0.15Ga0.63Al0.22As channels embedded in Al0.3Ga0.7As

We have measured impact ionization coefficients, α and β, in 150 Å pseudomorphically strained materials for the first time. The measurements were made on specially designed lateral p‐i‐n diodes. α and β in lattice‐matched GaAs layers are found to be lower than those in strained In0.2Ga0.8As and higher than those in strained In0.15Ga0.63Al0.22As. β is larger than α in all the samples. The results are discussed in terms of the changes in the band structure due to biaxial strain.  Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/70006/2/JAPIAU-73-1-465-1.pd

Stillbirth in a Tertiary Care Referral Hospital in North Bengal - A Review of Causes, Risk Factors and Prevention Strategies

Background and Aims: Stillbirth is one of the most common adverse outcomes of pregnancy, accounting for half of all perinatal mortality. Each year approximately 4 million stillbirths are reported, with 97% occurring in developing countries. The objective of the present study was to evaluate the stillbirth rate, exploring the risk factors and causes of stillbirth and suggest policies to reduce it. Settings and Design: A retrospective study of stillbirth among all deliveries over 5 years at North Bengal Medical College, a referral tertiary care teaching hospital in a rural background. The stillbirth rate and its trend were defined and the probable causes and risk factors were identified. Results: Stillbirth rate is 59.76/1000 live births, and Perinatal Mortality 98.65/1000 births. Of the still births, 59.72% were fresh and 40.27% were macerated. Among the causes of stillbirths, poor antenatal attendance and low socioeconomic status were important; other risk factors included prematurity, PIH, birth asphyxia, poor intrapartum care including prolonged and obstructed labour. In 23% cases, the cause remained unexplained. Conclusion: In addition to poor antenatal care, low socioeconomic condition, poor referral service, suboptimal intrapartum care in health facilities including tertiary centre were mainly responsible for majority of still births which could have been prevented. We speculate that upgrading the existing health system performance, particularly high quality intrapartum care by skilled health personnel, will reduce stillbirths substantially in our institut