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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]

Abstract Radiation-induced hardening of newly developed Ti/Ta-added reduced activation ferritic-martensitic (RAFM) steel is evaluated by combining self-ion irradiation and cross-sectional micropillar compression tests. 500-nm micropillars were fabricated on a cross-section polished surface using argon ion beam at locations of the ion-irradiated and unirradiated layers. The compressed micropillars showed that the deformation mode and flow behavior were changed because of ion irradiation. The radiation-induced increase in yield strength was evaluated by considering the specimen size effects manifested in the micropillar compression tests. The evaluated radiation hardening of the Ti/Ta-added RAFM steel at the dose of ∼2 dpa was found to be comparable to that of the reference RAFM steel with a composition similar to Eurofer97. The size and the number density of radiation-induced dislocation loops are analyzed, and the difference between the two RAFM steels is discussed. [ABSTRACT FROM AUTHOR]

BACKGROUND Treatment of atrophic scars using a fractional laser resurfacing technique has demonstrated favorable outcomes. OBJECTIVE To evaluate the efficacy and safety of 2,790-nm-wavelength ablative fractional resurfacing on atrophic acne scars in Asian individuals. METHODS Twenty participants (8 female, 12 male, mean age 26) with skin phototype IV and atrophic acne scars were treated with two sessions of 2,790-nm ablative fractional resurfacing laser at a 6-week interval. Objective and subjective (clinical evaluation by two blinded dermatologists) assessments were obtained at baseline and 1 and 3 months after the final treatment. RESULTS At the 3-month follow-up, 70% of the participants were rated as having at least 50% to 89% improvement of scars. Mild erythema was the most common adverse effect, observed in 30% of participants, but resolved completely in an average of 5 days. CONCLUSIONS Yttrium scandium gallium garnet ablative fractional resurfacing (2,790-nm) appears to be effective and well tolerated for the treatment of atrophic acne scars in Asians. The authors have indicated no significant interest with commercial supporters. [ABSTRACT FROM AUTHOR]

Background: There are few publications on the treatment options for facial pore size reduction. A focused therapy is needed. Objective: To evaluate the efficacy of selective photodynamic therapy (PDT) using an optic fiber for the size reduction of large facial pores. Methods: A series of five patients (skin phototypes IV-V) with large facial pores received two successive weekly treatments with an 810-nm diode laser using a fine optic fiber after indocyanine green (ICG) was applied selectively to enlarged pores. Patients were evaluated using digital photography at each treatment session, and at 3 months post-operation. Clinical assessment scores were determined at each treatment session and follow-up visit. Patient satisfaction surveys were obtained at the end of the study. Results: All five participants who completed the 3-month follow-up gave a subjective assessment of reduction of facial pore size. Modest to excellent improvement was achieved. Conclusion: This study demonstrates that treatment with pin-point PDT using an optic fiber is a well-tolerated and effective regimen for the reduction of facial pore size. [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]

Background: Treatment for most cases of keratosis pilaris requires simple reassurance and general skin care recommendations. Many Asian patients find lesions due to pigmented keratosis pilaris to be cosmetically unappealing. Treatment of post-inflammatory hyperpigmentation using a 1064-nm Q-switched Nd:YAG laser with low fluence is reported. Objective: To investigate the efficacy of a novel Q-switched Nd:YAG laser for the treatment of pigmented keratosis pilaris in Asian patients. Methods: Ten patients with pigmented keratosis pilaris underwent five weekly treatments using a Q-switched Nd:YAG laser (RevLite®®; HOYA ConBio®®, Freemont, CA, USA) at 1064 nm with a 6-mm spot size and a fluence of 5.9 J/cm2. Photographic documentation was obtained at baseline and 2 months after the final treatment. Results: Clinical improvement was achieved in all 10 patients with minimal adverse effects. Conclusion: For the treatment of keratosis pilaris, the use of a Q-switched Nd:YAG laser can be helpful for improving cosmetic appearance as it can improve pigmentation. [ABSTRACT FROM AUTHOR]

• Investigation of He effects in Ti/Ta-RAFM by irradiation with He ions at room temperature then annealed at 350 °C for 2h. • The radiation-induced swelling studied by step-height measurements. • The step heights increased with increasing tempering temperature of Ti/Ta-RAFM. • TEM analysis of helium bubbles preferentially formed on grain boundaries and particle-matrix interfaces. The swelling of a newly developed Ti/Ta-added reduced-activation ferritic/martensitic (RAFM) steel is evaluated using helium ion implantation. He ions are injected into sample surfaces covered with a transmission electron microscopy (TEM) grid; subsequent post-implantation annealing (PIA) causes surface mounds to form where He ions are injected. The heights of surface mounds on Ti/Ta-RAFM steels tempered at three different temperatures are found to increase with increasing tempering temperature. TEM observation reveals that helium bubbles formed along lath/block boundaries, dislocations, and precipitate-matrix interfaces. The increased step height of the Ti/Ta-RAFM steel tempered at higher temperature can be attributed to increases in the block and precipitate sizes and a decrease in dislocation density. The mechanism of helium bubble evolution in RAFM steel after helium implantation at room temperature and subsequent PIA is illustrated schematically. The swelling of Ti/Ta-RAFM steel is compared to that of a reference steel with a composition similar to that of Eurofer97. [ABSTRACT FROM AUTHOR]

This study presents an experimental approach to address sulfur-induced embrittlement in copper alloys. Building on recent theoretical insights, we identified specific solute elements, such as silicon and silver, known for their strong binding affinity with vacancies. Through experimental validation, we demonstrated the effectiveness of Si and Ag in preventing sulfur-induced embrittlement in copper, even though they are not typical sulfide formers such as zirconium. Additionally, our findings highlight the advantages of these elements over traditional solutes, such as their high solubility and propensity to accumulate along grain boundaries. This approach may have the potential to be applied to other metals prone to sulfur-induced embrittlement, including nickel, iron, and cobalt, offering broader implications for materials engineering strategies and alloy development. [ABSTRACT FROM AUTHOR]

The role of microstructures on the overall yield strength of garter-spring coil X-750 alloy used for the fuel channel structure in the Canada deuterium uranium reactor is investigated in this study. We perform a comprehensive characterization of the residual microstructures in the garter-spring coil X-750 alloy and heat-treated plate X-750 alloys using electron microscopy. Simultaneously, we perform small-scale mechanical tests and bulk mechanical tests to evaluate the yield strength of the compact garter-spring coil component. We compare the mechanical property data obtained via the micro-bending measurement method and derive a correlation between each measured data point to assess the increase in yield strength. The γ′ ordering phase contribution is the most crucial factor in strengthening, followed by dislocation density and boundary-decorated precipitates in the garter-spring coil X-750 alloy. We quantitatively evaluate the effects of the γ′ ordering phase and initial dislocation density on the yield strength of the garter spring coil X-750 alloy because they significantly affect the change in the mechanical properties in the irradiation environment. [ABSTRACT FROM AUTHOR]

Additive manufacturing (AM) enables the rapid fabrication of complex shapes using engineering materials such as austenitic stainless steels and can imbue them with high irradiation resistance for use in reactor components. This is attributed to their refined grain structure and high grain boundary area. In this study, austenitic stainless steels (type 304) fabricated via direct energy deposition (DED) and powder bed fusion (PBF) techniques were irradiated with 5 MeV He ions to an approximate dose of 0.6 dpa at 300°C; subsequently, they were characterized through electron microscopy and the micro tensile testing. The results revealed that austenitic stainless steels manufactured using AM methods exhibited outstanding mechanical performance. The high performance of austenitic stainless steels fabricated through the DED technique can be attributed to their high tensile strength and excellent ductility elongation. This excellent performance is believed to be caused by the low stacking fault energy and the corresponding martensite formation during deformation. In particular, it was found that better mechanical properties were maintained even after helium irradiation, which is an important result obtained from the micro-tensile test. Even a small variation in the chemical composition and sub-microstructure of AM materials could result in improved irradiation tolerances. [ABSTRACT FROM AUTHOR]

HT9, a ferritic/martensitic steel, is a candidate structural material for next-generation advanced reactors. Its microstructure is a typical tempered martensite showing a hierarchical lath-block-and-packet structure. We investigate the specimen size effect and strengthening contribution of various microstructural boundaries manifested in the compression tests of micropillars with diameters ranging from 0.5 to 17 μm. It is observed that micropillars with diameters larger than 3 μm show uniform deformation and plastic flow curves comparable to the bulk flow curve. Localized deformation by a few pronounced slip bands occurs in micropillars with diameters smaller than 1 μm, and the yield strength is reduced. Careful examination of the sizes of the microstructural features and cross-sections of the micropillars shows that the block boundaries are the most effective strengthening boundaries in tempered martensitic microstructure. The bulk mechanical properties of HT9 can be evaluated from a micropillar with diameter as low as 3 μm. [ABSTRACT FROM AUTHOR]

We evaluated the effects of some dietary natural mineral materials as an antibiotic replacer based on growth performance, non-specific immune responses and disease resistance in juvenile and subadult rainbow trout, Oncorhynchus mykiss. First experiment, juvenile rainbow trout averaging 2.7 ± 0.02 g (mean ± SD) were fed one of the six experimental diets; a basal commercial diet as a control ( CON), CON with oxytetracycline ( OTC), with yellow loess ( YL), with Macsumsuk® ( MS), with Song-Gang® stone ( SG) and with barley stone ( BS) at 0.4% of each diet. At the end of 8-week feeding trial, weight gain ( WG), specific growth rate ( SGR), feed efficiency ( FE) and protein efficiency ratio ( PER) of fish fed YL diet were significantly higher than those of fish fed CON diet. Non-specific immune responses such as superoxide dismutase ( SOD), myeloperoxidase ( MPO), lysozyme ( LYS) activity and oxidative radical production of fish fed YL diet were higher than those of fish fed CON diet. At the end of 15 days of challenge test with Aeromonas salmonicida, average cumulative survival rate of fish fed YL diet was significantly higher than that of fish fed BS and CON diets. However, there were no significant differences among fish fed YL, SG and OTC diets. Second experiment, subadult rainbow trout averaging 261.5 ± 3.5 g (mean ± SD) were fed one of the four experimental diets for 22 weeks: CON, and CON with OTC, YL or SG at 0.4% of each diet. At the end of feeding, growth performance of fish fed SG and YL diets was significantly higher than that of fish fed CON diet. Non-specific immune responses in terms of SOD, MPO, LYS and NBT of fish fed SG and YL diets were significantly higher than those of fish fed CON diet. However, there were no significant differences among the fish fed YL, SG and OTC diets. The results indicate that dietary yellow loess or Song-gang® stone at 0.4% of diet could replace oxytetracycline in juvenile and subadult rainbow trout. [ABSTRACT FROM AUTHOR]

N-type and p-type silicon were irradiated by neutrons and protons from low to high fluence range (108 − 1011 cm-2 for neutrons and 1010 − 1013 cm-2 for protons). The carrier recombination lifetime of each irradiated silicon was measured using a microwave photoconductance decay method, and the resistivity of the irradiated silicon was also measured. Both neutron and proton irradiation induced a similar lifetime at the same irradiation fluence. The defect formation rates were determined to vary with irradiation fluence from the inverse lifetime dependence on irradiation fluence. The sheet resistance was increased above a threshold fluence. The result shows that at least three different values of defect formation rate are present in the fluence range of 109 − 1015 cm-2, and it may have potential for practical use as low-dose dosimeters. • Irradiation of Si wafers by neutrons and protons from low to high fluence range. • Defect formation rates determined from the inverse carrier lifetimes dependence on irradiation fluence. • Fluence-dependent lifetime changes of Si have strong potential for practical use. [ABSTRACT FROM AUTHOR]