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The competition between forward stimulated Raman side scatter (FSRSS) and backward stimulated Raman side scatter (BSRSS) is investigated in inhomogeneous plasma using particle-in-cell (PIC) simulations. Experimental observations at the National Ignition Facility have demonstrated the significance of stimulated Raman side scatter or backscatter instability compared to two-plasmon-decay under ignition-scale conditions for various laser beam geometries. Side scatter refers to the geometry where the Raman scattered light is generated in a direction perpendicular to the local density gradient. For an obliquely incident pump, the scattered light can either copropagate (FSRSS) or counter propagate (BSRSS) with respect to the pump. Under ignition-scale conditions, linear analysis shows that both BSRSS and FSRSS are absolutely unstable (temporally growing) at higher densities ( n e ∼ 0.2 n c ), whereas at lower densities ( n e ∼ 0.1 n c ), BSRSS becomes convective with substantial gain, while FSRSS remains absolute. Two-dimensional PIC simulations demonstrate that the competition between BSRSS and FSRSS is sensitive to the density. BSRSS tends to dominate at higher densities, while FSRSS becomes dominant at lower densities. At moderate densities ( n e ∼ 0.15 n c ), FSRSS and BSRSS coexist. Furthermore, an increase in laser intensity leads to enhanced electron trapping, which kinetically strengths and then saturates BSRSS in the lower density region. [ABSTRACT FROM AUTHOR]

Objective: To investigate the clinical features and the value of different diagnostic indices for etiology in reproductive age women with hyperandrogenism. Methods: The medical records of 96 reproductive age women with hyperandrogenism in the multi-disciplinary team of Peking University First Hospital from January 2020 to April 2021 were collected. The patients were divided into four groups based on final diagnosis: congenital adrenal hyperplasia (CAH) ( n =8), polycystic ovary syndrome (PCOS) ( n =67), idiopathic hyperandrogenism ( n =13) and other specific diseases ( n =8), respectively. The indices related to androgens in different groups were compared, and then their efficiency for diagnosis of CAH and PCOS were analyzed with receiver operator characteristic curve (ROC curve). Results: A total of 96 patients with hyperandrogenism were recruited, with the age of 19-45 (29±6) years old. Overall, 4.2% (4/96) of the patients were with single clinical hyperandrogenism, 56.3% (54/96) were with single laboratory hyperandrogenaemia and 39.6% (38/96) were with both. The breakdown into laboratory hyperandrogenaemia subtypes was as follows: only T elevation 22.8% (21/92), only A2 elevation 7.6% (7/92), none DHEAS elevation, only FAI elevation 5.4% (5/92) and elevation of more than one of the androgen indices mentioned above accounted for 64.1% (59/92). In the reasons of consultation, simple irregular menstruation (36.0%, 32/89) or accompanied by clinical hyperandrogenism with or without infertility (36.0%, 32/89) were the most common. As for primary visiting departments, Obstetrics and Gynecology accounted for 53.2% (51/96), and then Endocrinology as 39.5% (38/96). The 17-OHP level of CAH, PCOS and idiopathic hyperandrogenism group was 20.0 (8.2, 33.1), 1.1 (0.8, 1.4), 0.9 (0.8, 1.3) ng/ml, respectively. The androstenedione level in these groups was 6.3 (4.6, 8.7), 3.8 (2.9, 4.8) and 3.2 (2.7, 3.7) ng/ml, respectively. The 17-OHP and androstenedione levels of CAH group were significantly higher than that in PCOS or idiopathic hyperandrogenism group (all P <0.05). The ratio of LH and FSH in these three groups was 0.8(0.5, 1.0), 1.3(0.6, 1.9) and 0.6(0.3, 0.7), respectively. The ratio of LH and FSH was significantly higher in PCOS than that in idiopathic hyperandrogenism group ( P =0.024), but yet there was no significant difference compared with CAH group ( P >0.05). The AUC of ROC curve of 17-OHP for CAH diagnosis was 0.94, followed by androstenedione 0.83, whereas LH/FSH for PCOS diagnosis was only 0.63. Conclusions: Among the reasons of consultation in reproductive age women who visited our multi-disciplinary team for female hyperandrogenism, simple irregular menstruation or accompanied by clinical hyperandrogenism with or without infertility are the most common. PCOS accounts for the majority of different androgen excess disorders. 17-OHP is the most valuable parameter for the diagnosis of CAH and secondly androstenedione.