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Background:. Emerging as an adjunct to breast-conserving surgery, oncoplastic breast surgery seeks to improve the cosmetic and functional outcomes for breast cancer surgery. The objective was to assess the potential advantages of using the latissimus dorsi (LD) flap, in comparison with local tissue rearrangement, in terms of aesthetic results and postoperative problems. Methods:. This study compared the outcomes of patients with a malignant tumor removed from the upper outer quadrant of the breast using a comparative nonrandomized control approach. Participants were split into two groups: reconstruction using local tissue rearrangement was performed on 20 patients (group A), and a pedicled LD flap was used to treat the same number of patients (group B). All patients were examined in the clinics’ outpatient setting. Every 3 months, the medical oncology team would do a thorough clinical assessment. Results:. Better aesthetic outcomes were significantly higher among patients with an LD flap. The LD flap was able to maintain breast shape in 90%, breast volume in 85%, and the nipple-areola complex direction in 90% of patients. Surgeons’ evaluation of both techniques reported significantly higher satisfaction for LD flap than local tissue replacement. Patient satisfaction was significantly higher among patients with an LD flap. With regard to the postoperative complications, there were no significant differences between either group. Conclusions:. Oncoplastic breast surgery with reconstruction using the pedicled LD flap provides maintenance of the shape of female breasts with better aesthetic outcomes and patient and surgeon satisfaction than reconstruction using local tissue rearrangement, with a comparable complication rate.

Paschen curves were studied using different cathode materials such as magnesium, zinc, and carbon graphite by discharge in argon gas of a pressure range between 0.08 and 3 Torr using a parallel plates configuration. The first and second Townsend coefficients ([alpha] and [gamma], respectively) and the ionization efficiency ([eta]) of different cathode materials were deduced from Paschen curves as a function of the reduced field (E/P). The minimum breakdown voltage was found to be about 242 V for Mg material, which has the lowest work function, while carbon graphite has a higher breakdown voltage of 283 V due to its higher work function. The second coefficient [gamma] was increased as a function of E/P and has higher values for materials of lower work functions, and a similar trend of [gamma] is obtained as a function of the ion mean energy. On the other hand, the first coefficient [alpha] has a reverse behavior with both E/P and the work function of the cathode materials compared with the second coefficient. The ionization efficiency of the three cathode materials is identical, as [eta] depends only on the gas properties and not the cathode material. [eta] has a maximum value of about 0.025 [V.sup.-1] for an E/P of about 185 V[cm.sup.-1][Torr.sup.-1], corresponding to the maximum ionizing ability of electrons. The validation of the breakdown results has been confirmed by conferring with other published experimental measurements. Key words: gas breakdown, Paschen curves, cathode work function, first Townsend coefficient, second Townsend coefficient, ionization efficiency. Nous etudions les courbes de Paschen en utilisant des cathodes faites de differents materiaux, a savoir le magnesium, le zinc et le graphite. Les decharge dans un gaz d'argon a une pression allant de 0.08 a 3 Torr, sont faites en utilisant la configuration des plaques paralleles. Nous deduisons les premier et deuxieme coefficients de Townsend ([alpha] et [gamma] respectivement) et l'efficacite d'ionisation ([eta]) des differentes cathodes, a partir des courbes de Paschen en tant que fonctions du champ reduit (E/P). Nous trouvons que la tension de claquage minimale, a 242 V, appartient au Mg qui a le plus bas travail de sortie, alors que pour le graphite, le claquage est a 283 V, a cause de sa plus haute valeur de travail de sortie. Le second coefficient [gamma] est une fonction croissante de E/P et a ses plus hautes valeurs pour les materiaux de plus faible energie de sortie et [gamma] a une tendance similaire en fonction de l'energie moyenne de l'ion. D'un autre cote, le premier coefficient [alpha] a un comportement inverse de [gamma] vis-a-vis de E/P et du travail de sortie de la cathode. L'efficacite d'ionisation des trois types de cathode est identique, parce que [eta] ne depend que des proprietes du gaz, et non du materiau de la cathode. y a une valeur maximale d'environ 0.025 [V.sup.-1] pour E/P d'environ 185 V[cm.sup.-1][Torr.sup.-1], correspondant a la valeur maximale de la facilite d'ionisation des electrons. La validation de ces resultats de claquage a ete confirmee par comparaison avec d'autres mesures experimentales deja publiees. [Traduit par la Redaction] Mots-cles : claquage dans un gaz, courbes de Paschen, travail de sortie de la cathode, premier coefficient de Townsend, second coefficient de Townsend, efficacite d'ionisation., Introduction Electric breakdown of gases is a process in which neutral gas is transformed into a conducting state [1]. The breakdown voltage [V.sub.b] is a function, mainly, of the gas [...]

Paenibacillus durus strain ATCC 35681T is a Gram‐positive diazotroph that displayed capability of fixing nitrogen even in the presence of nitrate or ammonium. However, the nitrogen fixation activity was detected only at day 1 of growth when cultured in liquid nitrogen‐enriched medium. The transcripts of all the nifH homologues were present throughout the 9‐day study. When grown in nitrogen‐depleted medium, nitrogenase activities occurred from day 1 until day 6 and the nifH transcripts were also present during the course of the study albeit at different levels. In both studies, the absence of nitrogen fixation activity regardless of the presence of the nifH transcripts raised the possibility of a post‐transcriptional or post‐translational regulation of the system. A putative SigA box sequence was found upstream of the transcription start site of nifB1, the first gene in the major nitrogen fixation cluster. The upstream region of nifB2 showed a promoter recognizable by SigE, a sigma factor normally involved in sporulation. [ABSTRACT FROM AUTHOR]

To overcome the discontinuity between the axial phase and the radial phase in the plasma focus, a new model (the Masoud model) has been developed. It is assumed that, according to the snowplough model, the radial phase moves in the angular direction with continuity between the axial and the radial phases. This model is based on the introduction of an angle of motion in all equations of motion and circuit. Then, the plasma sheath position and velocity were calculated numerically from the previous equations. A slug model has been used to calculate the shock wave velocity, and hence the electron temperature. Values of the discharge current, the axial speed, the axial position, the spike voltage, the radial piston speed, the radial piston position, the plasma column length and the plasma temperature have been obtained using the new model. The values calculated by using this model show good agreement with the published experimental results. [ABSTRACT FROM AUTHOR]