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41.
BACKGROUND: The retrocervical area of the pelvis is a particularly strategic location for dyspareunia-producing endometriotic lesions. Because this area is often hidden from view by the cervical bulge, it is necessary that close attention be paid to locating occult disease. CASE: A 35-year-old, white female underwent repeat laparoscopy for persistent dyspareunia. Occult retrocervical disease was found and exercised. CONCLUSION: Incomplete treatment may result if this area is not examined and biopsied. 相似文献
42.
Safwat Mena Elgammal Ali AbdAllah Eslam G. Azer Marianne A. 《Mobile Networks and Applications》2022,27(3):1327-1336
Mobile Networks and Applications - The Internet Protocol (IP) architecture could not fully satisfy the Vehicular Ad-hoc Networks (VANETs) needed efficiency, due to their dynamic topology and high... 相似文献
43.
Florencia Gómez Miguel Nussbaum Juan F. Weitz Ximena Lopez Javiera Mena Alex Torres 《International Journal of Computer-Supported Collaborative Learning》2013,8(2):225-244
The benefits of collaborative learning are well documented. However, most of the research has been done with children beyond the ages of early childhood. This could be due to the common and erroneous belief that young children have not developed the capacity to work collaboratively toward a given aim. In this paper we show how small group co-located collaborative learning on a single display computer improves oral language, logical-mathematical and social skills in pre-school children. Considering that early childhood teachers have a responsibility to provide a supportive environment, teacher mediation is essential in order to achieve collaborative learning. Thus, teachers were trained in the use of the technology and strategies for effective collaborative learning. The study was implemented in 10 kindergarten classrooms with 268 children between the ages of 5 and 6 years old. A group of 5 kindergarten classrooms with equivalent characteristics participated as a comparison group. During the four-month intervention, children worked on collaborative activities at least twice a week. A quasi-experimental approach was used to assess the implementation, including pre- and post-testing. The data showed differences in the learning of oral language, logical-mathematical and social skills, with the experimental group demonstrating significantly greater achievement. 相似文献
44.
Abstract. An approach to constructing strictly stationary AR(1)‐type models with arbitrary stationary distributions and a flexible dependence structure is introduced. Bayesian nonparametric predictive density functions, based on single observations, are used to construct the one‐step ahead predictive density. This is a natural and highly flexible way to model a one‐step predictive/transition density. 相似文献
45.
Dr. Camille Decroocq Dr. Antoine Joosten Raphaël Sergent Teresa Mena Barragán Prof. Carmen Ortiz Mellet Prof. Philippe Compain 《Chembiochem : a European journal of chemical biology》2013,14(15):2038-2049
In view of recent reports of a strong multivalent effect in glycosidase inhibition, a library of β‐CD‐based multivalent iminosugars has been efficiently synthesized by way of CuI‐catalyzed azide–alkyne cycloaddition (CuAAC). In combination with the first application of isothermal titration calorimetry (ITC) experiments to the study of multivalent iminosugar–enzyme interactions, the inhibition properties of these click clusters were evaluated on a panel of glycosidases. The structural parameters that were varied include valency, peripheral ligand structure, and topology. The inhibition results obtained with the iminosugar clusters further highlight the importance of multivalency in the inhibition of α‐mannosidase. Generally, the evaluated multivalent iminosugars displayed comparable thermodynamic signatures of binding towards α‐mannosidase (Jack bean): that is, large negative enthalpies of complexation coupled with small entropies of either sign. In addition, the enthalpy–entropy compensation observed in all tested cases may be attributed to a common mechanism of dissociation for the enzyme–multivalent iminosugar interactions. The measured binding stoichiometries indicated that each iminosugar cluster interacts with no more than one protein molecule. 相似文献
46.
Degenerate codon libraries are frequently used in protein engineering and evolution studies but are often limited to targeting a small number of positions to adequately limit the search space. To mitigate this, codon degeneracy can be limited using heuristics or previous knowledge of the targeted positions. To automate design of libraries given a set of amino acid sequences, an algorithm (LibDesign) was developed that generates a set of possible degenerate codon libraries, their resulting size, and their score relative to a user-defined scoring function. A gene library of a specified size can then be constructed that is representative of the given amino acid distribution or that includes specific sequences or combinations thereof. LibDesign provides a new tool for automated design of high-quality protein libraries that more effectively harness existing sequence-structure information derived from multiple sequence alignment or computational protein design data. 相似文献
47.
A simple rate-equation-based thermal VCSEL model 总被引:3,自引:0,他引:3
Mena P.V. Morikuni J.J. Kang S.-M. Harton A.V. Wyatt K.W. 《Lightwave Technology, Journal of》1999,17(5):865-872
Motivated by the potentially large number of devices and simulations involved in optoelectronic system design, and the associated need for compact optoelectronic device models, we present a simple thermal model of vertical-cavity surface-emitting laser (VCSEL) light-current (LI) characteristics based on the laser rate equations and a thermal offset current. The model was implemented in conventional SPICE-like circuit simulators, including HSPICE, and used to simulate key features of VCSEL LI curves, namely, thermally dependent threshold current and output-power roll-over for a range of ambient temperatures. The use of the rate equations also allows simulation in other non-dc operating regimes. Our results compare favorably to experimental data from three devices reported in the literature 相似文献
48.
C Huerta Sánchez C García Julián D Fernández Tejedor MA de Mena Mogrobejo JV Tato Lobo 《Canadian Metallurgical Quarterly》1998,9(3):121-126
Sirenomelia or the mermaid syndrome is a rare birth defect, often combined with severe malformations of the urogenital system and the lower gastrointestinal tract. The incidence is about one case in 60,000. Ultrasound can be very important in early detection of this deformity. Because of the high incidence of oligohydramnios amnioninfusion could be helpful. Also a magnetic resonance radiographia in the prenatal period could be performed. We report three cases of sirenomelia and in addition the literature is reviewed and discussed. 相似文献
49.