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This study investigates the microstructure and nano-hardness distribution across the thickness of an H-section steel beam, specifically designed for seismic and fire resistance and fabricated using a quenching and self-tempering process. The beam dimensions include a 24 mm thick flange, with flange and web lengths of 300 mm and 700 mm, respectively. Our findings indicate that the mechanical properties across the flange thickness meet the designed criteria, with yield strengths exceeding 420 MPa, tensile strengths of over 520 MPa, and a yield-to-tensile strength ratio below 0.75. Microstructurally, the central part of the flange predominantly consists of granular bainite with a small fraction of martensite–austenite (MA) constituents, while locations closer to the surface show increased acicular ferrite and decreased MA constituents due to faster cooling rates. Furthermore, thermal exposure at 600 °C reveals that while the matrix microstructure remains thermally stable, the MA phase undergoes tempering, leading to a decrease in nano-hardness. These insights underline the significant impact of MA constituents on the elongation properties and stress concentrations, contributing to the overall understanding of the material's behavior under seismic and fire conditions. The study's findings are crucial for enhancing the reliability and safety of construction materials in demanding environments. [ABSTRACT FROM AUTHOR]

This study examines whether politicians exhibit gender bias in responsiveness to constituents' requests for public service delivery improvements in Uganda. We leverage an in-person survey experiment conducted with 333 subnational politicians, of which one-third are elected to women's reserved seats. Politicians hear two constituents request improvements in staff absenteeism in their local school and health clinic and must decide how to allocate a fixed (hypothetical) budget between the two improvements. The voices of the citizens are randomly assigned to be (1) male-school, female-health or (2) female-school, male-health. We find no evidence of gender bias toward men versus women, or toward same-gender constituents. This study expands on the mixed results of prior studies examining gender bias in politician responsiveness (typically over email) by adding a critical new case: a low-income context with women's reserved seats. [ABSTRACT FROM AUTHOR]

Despite a burgeoning interest in studying the effects that traditional leaders have on service delivery and political accountability, scholars have paid little attention to political competition and its role in accountability for the unelected leaders. This article investigates these questions leveraging original surveys collected from 684 village-level traditional leaders (658 for the second round), 680 members of their ruling family, and 669 secretaries of the leaders in Central Malawi. This study first establishes that leadership contestation appeared in 14 percent of the leadership positions, which challenges the conventional belief that such disputes occur who exceptionally rarely for such hereditary positions. The in-depth analyses in this article demonstrate that traditional leaders' legitimacy stems from the support from their ruling family, and that the family wields significant power in the installation and removal of the leader as selectors. This work further finds that traditional leaders who experienced competitive challenges exhibit a higher propensity to share the resources at their disposal with their ruling family than other leaders who did not encounter the challenges. The findings align with the theoretical expectation that leaders who undergo competitive challenges adopt a heightened sense of the importance of the ruling family and are incentivized to buy their loyalty because securing this support or the lack thereof significantly affects the leaders' fate and authority. Finally, this article expands on the recent studies concerning competition in traditional leadership by shifting the focus to the ruling family – the kingmakers behind the scenes – and discusses the ramifications of this phenomenon on political accountability. [ABSTRACT FROM AUTHOR]

Background: RF-pulsed light with ELOS technology devices have recently been used to treat acne vulgaris in selected patients. Objective: To investigate the safety and efficacy of a combination of two kinds of device with ELOS technology for the treatment of acne. Methods: Ten patients with moderate acne were treated twice weekly for 4 weeks with the Aurora AC® (Syneron Medical Ltd, Yokneam, Israel), a combination of pulsed light and RF energy. Immediately after Aurora AC treatment, all patients were treated weekly only on one facial half with the Matrix IR® (Syneron Medical Ltd), a combination of fractional diode laser and RF energy. Photographic documentations were obtained at baseline, before each treatment session, and 1 and 3 months after the final treatment. Results: At 3 months after treatment, the mean lesion count was reduced by 38% (p<0.05) after eight treatments with the Aurora AC alone. With additional treatment with the Matrix IR, the mean lesion count was reduced by 61%. Conclusion: The combination of Aurora AC and Matrix IR was superior in reducing the acne lesion count, and in extending the length of the remission period. [ABSTRACT FROM AUTHOR]

Ablative laser resurfacing is an effective treatment for atrophic acne scars. However, it often induces complications such as edema, prolonged erythema, scarring and hyperpigmentation. Therefore, a new concept of laser treatment called fractional photothermolysis has been designed to create microscopic thermal wounds to achieve skin rejuvenation treatment of atrophic acne scars. This study was designed to prospectively evaluate the use of a technique similar to fractional photothermolysis using only the standard CO2 laser without the fractional laser device in the treatment of atrophic scars and demonstrates it as a safe, effective and economical treatment option. Clinical improvement was achieved in all 35 patients with minimal adverse effects. [ABSTRACT FROM AUTHOR]

Q-switched mode lasers have been utilized for treatment of many pigmentary lesions. Because of their short pulse durations (1-100 ns), these lasers selectively destroy pigment laden cells while sparing the surrounding normal tissues. To determine if the Q-switched alexandrite laser (QSAL) is effective in the treatment of congenital melanocytic nevi, 53 patients with these lesions were treated with QSAL; of these, 16 also received CO(2) laser treatment between QSAL treatments. We observed an average improvement score in the 53 treated patients of 2.623 + 1.13, corresponding to a 72% improvement. Treatment with the combination of QSAL and a CO(2) laser resulted in a significant enhancement of improvement score (3.06 +/- 1.18) compared to patients treated with the QSAL alone (2.43 +/- 1.07; p = 0.0393). Complications were mild, with 35 nevi (67.3%) showing textural change of skin after treatment, 2 (3.8%) showing depressed scar formation, and 4 (7.5%) showing hypertrophic changes, while 12 nevi (23%) showed no changes. Hypopigmentation was observed in 16 patients (30%), and hyperpigmentation was observed in 15 patients (28%) 48 weeks after the final QSAL treatment. Repigmentation to a brown to black spot was observed in 44/53 (83%) patients within an average of 5.45 +/- 3.93 months. These results indicate that the QSAL was as effective as other Q switch mode lasers in the treatment of congenital melanocytic nevi, but repigmentation is a problem.