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Placenta accreta is a rare but potentially life-threatening condition in which the placenta invades the myometrium of the uterus. It is more common in women with a history of previous cesarean delivery, placenta previa, or uterine surgery. The diagnosis of placenta accreta can be challenging and is often madeintraoperatively or postoperatively. A 36-year-old gravida 4 para 3 woman presented with postpartum hemorrhage due to placenta accreta that was diagnosed by an anatomopathology exam. The management of postpartum hemorrhage typically involves several steps to stabilize the patient and control bleeding. In this case, the patient was resuscitated with intravenous fluids and blood transfusions, given uterotonic medications, and underwent emergency laparotomy to remove her uterus. An anatomopathology exam confirmed the diagnosis of placenta accreta, which had not been suspected during the initial assessment. The patients postoperative course was uneventful, and she was discharged on the seventh postoperative day. The management of PPH due to placenta accreta requires a multidisciplinary approach involving obstetricians, anesthesiologists, hematologists, and interventional radiologists. The initial management of PPH involves resuscitation and stabilization of the patient. The next step is to control bleeding by uterine massage and administration of uterotonic agents. If bleeding persists despite uterine massage and administration of uterotonic agents, surgical intervention should be considered, which includes uterine artery embolization, hysterectomy, and conservative management. The choice of surgical management depends on the severity of bleeding, hemodynamic stability, and the extent of placental invasion. Early diagnosis and management of placenta accreta are essential for the prevention of adverse outcomes, and a multidisciplinary approach is crucial for the successful management of this condition. &nbsp

The impact ionization in semiconductor materials is a process that produces multiple charge carrier pairs from a single excitation. This mechanism constitutes a possible road to increase the efficiency of the p-n and p-i-n solar cells junctions. Our study considers the structure of InN/InGaN quantum dot solar cell in the calculation. In this work, we study the effect of indium concentration and temperature on the coefficient θ of the material type parameter of the impact ionization process for a p(InGaN)-n(InGaN) and p(InGaN)-i(QDs-InN)-n(InGaN) solar cell. Next, we investigate the effect of perturbation such as temperature and indium composition on conventional solar cell’s (p(InGaN)-n(InGaN)) and solar cells of the third generation with quantum dot intermediate band IBSC (p(InGaN-i(QD-InN)-n(InGaN)) by analyzing their behaviour in terms of efficiency of energy conversion at the presence of the impact ionization process. Our numerical results show that the efficiency is strongly influenced by all of these parameters. It is also demonstrated that θ decreased with the increase of indium concentration and temperature which contributes to an overall improvement of the conversion efficiency.

The behavior of InN/InxGa1-xN spherical quantum dots solar cell is investigated, considering the internal electric field induced by the polarization of the junction. In order to determine the position of the intermediate band (IB), we present an efficient numerical technique based on difference finite method to solve the 3D time-independent Schrodinger's equation in spherical coordinates. The resultant n × n Hamiltonian matrix when considering n discrete points in spatial direction is diagonalized in order to calculate energy levels. Thus, the interband and intersubband transitions are determined, taking into consideration the effect of the internal electric field, size dots, interdot distances, and indium content on the energy levels, optical transition, photo-generated current density, open-circuit voltage and power conversion efficiency of the QD-IBSCs.

Resume Les chirurgiens vasculaires utilisent une technique d’anastomose qui a fait ses preuves depuis longtemps. Cette technique de reference consiste a realiser une anastomose de vaisseaux tailles en palette a obliquite opposee. L’anastomose est alors realisee par une suture continue grâce a deux hemi-surjets. Cette technique nous semble adaptee a la microchirurgie et donner des resultats satisfaisants. Nous presentons les resultats de cette technique en chirurgie microvasculaire dans le cadre de reconstruction faciale.

With a view to measuring the temperature fluctuations in a heated turbulent air stream, the latter is traversed by a laser beam perpendicular to the flow. The ultimate aim is to access the temperature fluctuations along the laser’s path starting from the luminous dot projected by the laser on to a position probe placed at the stream output. Our initial task is to demonstrate that by solving an optimal control problem, it is possible to calculate the variable diffusion coefficient along the beam trajectory. The optimal control problem considered here is formulated in terms of a nonlinear system whose dynamics are described by a mathematical model developed with the Einstein–Fokker–Plank–Kolmogorov equation as starting-point, and where the control action is assumed given by the diffusion coefficient. A fresh approach to solving the problem based on the decomposition-co-ordination principle is introduced in order to solve the corresponding optimal control problem, i.e. to calculate the diffusion coefficient which meets required objectives.

As emi-classical approach is used to analyse how transverse effects and relaxation due to homogeneous and inhomogeneous broadening affect the dynamics of superfluorescence. Results are discussed in order to match our Te 2 data.

The unique properties of superfluorescence need a clear theoretical understanding. Our goal is to present a comparison of our experimental data on Te 2 superfluorescence with simulations based on semi-classical theory and mean field quantum theory. Quantitative agreement can be found with quantum theory results provided time dependance of the field is taken in account.

The dynamical process of superfluorescent Te 2 molecules coupled to the electromagnetic field of a resonant cavity is investigated. Enhancement of superfluorescent characteristics have been observed with different low loss linear plano-concave resonators.

Superradiance emission in simple systems is a topic of recent theoretical and experimental interest [l 41. It covers the collective radiation damping of an initially inverted assembly of atoms or molecules. The important features of time resolved superradiant emission (delay, intensity and shape) are determined by the number or the density N of cooperating partners. More interesting for spectroscopic applications are the following features : emitted intensity which increases upon N~ meanwhile halfwidth of bursts of radiation decrease as 11N. Hence we report new applications of such a phenomenon to very sensitive spectroscopy concerning hyperfine structure based on analysis of superradiant beats as well as applications to amplifier technology. As previously mentionned emitted intensity increases with density of partners meanwhile halfwidth of time evolution decreases as lldensity. One then has an efficient tool to explore weak emission phenomena such as metastable states or low radiative transitions by forcing such transitions to supperradiate. More promising is superradiant spectroscopy which is somewhat connected to quantum beats. Let us recall that when levels involved has no structure or their degeneracy is much smaller than the superfluorescence half-width, time evolution of the emitted light pulse can be represented by a smooth Lorentzian curve (see Fig. 1). However when level structure splittings are of the order of the half-width and upon coherent excitation modulations can be observed on the time-resolved superradiant signal which can be assigned to quantum beats. Yet these beat frequencies are somewhat different from the usual tern of quantum beats since in this case it may reflect either initial-level splittings, fmal-level splittings or a c-mbination of both. In this way we report here observation of beats arising from interference of non-degenerate coherently excited states in the superradiance of rotational transition in 125~e2 vapour and its application to hyperfime structure measurements.

Superfluorescence emitted from the output face of an initially inverted Te/sub 2/ vapor is found to exhibit ringing; when diffraction is not dominant, this is an intrinsic property of superfluorescence, and its aspects are compared to numerical integration of the Maxwell-Bloch equations. >

Vascular surgeons use an anastomosis technique that has proven its efficiency for a long time. This technique consists in an anastomosis with spatulated ended vessels designed with opposite obliquity. This anastomosis is closed by a continuous suture. Authors expose the results of this technique applied to microvascular surgery in facial reconstruction.

We report observation of beats in the time-resolved spectra of [sup 125]Te[sub 2] superfluorescence. The results are used to determine hyperfine contributions in the [ital B] 0[sub u][sup +] state.

High-resolution analysis results are presented for Te/sub 2/ superfluorescence induced by short pulses from a YAG-pumped dye laser pulses, and a comparison is made with CW-laser-induced fluorescence observed by Fourier transform spectroscopy. A complete identification of the transitions involved, based on intensity measurements and supported by calculated Franck-Condon factors, has been achieved. The cooperative emission in Te/sub 2/ has been studied by time resolved spectroscopy as a function of density. With increasing density or temperature of the sample, the emission changes continuously from characteristic spontaneous emission to superfluorescence. The evolution of the time characteristics of the signal with the number of partners are presented and compared with the predictions of current theories. >