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Aim: To compare eight large‐ and low‐tapered heat‐treated reciprocating instruments regarding their design, metallurgy, mechanical properties, and irrigation flow through an in silico model. Methodology: A total of 472 new 25‐mm E‐Flex Rex (25/.04 and 25/.06), Excalibur (25/.05), Procodile (25/.06), Reciproc Blue R25 (25/.08v), WaveOne Gold Primary (25/.07v), and Univy Sense (25/.04 and 25/.06) instruments were evaluated regarding their design (stereomicroscopy, scanning electron microscopy, and 3D surface scanning), metallurgy (energy‐dispersive X‐ray spectroscopy and differential scanning calorimetry), and mechanical performance (cyclic fatigue, torsional resistance, cutting ability, bending and buckling resistance). Computational fluid dynamics assessment was also conducted to determine the irrigation flow pattern, apical pressure, and wall shear stress in simulated canal preparations. Kruskal–Wallis and one‐way anova post hoc Tukey tests were used for statistical comparisons (α = 5%). Results: Instruments presented variations in blade numbers, helical angles, and tip designs, with all featuring non‐active tips, symmetrical blades, and equiatomic nickel‐titanium ratios. Cross‐sectional designs exhibited an S‐shaped geometry, except for WaveOne Gold. Univy 25/.04 and Reciproc Blue displayed the smallest and largest core diameters at D3. Univy 25/.04 and E‐Flex Rec 25/.04 demonstrated the longest time to fracture (p <.05). Reciproc Blue and Univy 25/.04 exhibited the highest and lowest torque to fracture, respectively (p <.05). Univy 25/.04 and Reciproc Blue had the highest rotation angles, whilst E‐Flex Rec 25/.06 showed the lowest angle (p <.05). The better cutting ability was observed with E‐Flex Rec 25/.06, Procodile, Excalibur, and Reciproc Blue (p >.05). Reciproc R25 and E‐Flex Rec showed the highest buckling resistance values (p <.05), with WaveOne Gold being the least flexible instrument. The impact of instruments' size and taper on wall shear stress and apical pressure did not follow a distinct pattern, although Univy 25/.04 and E‐Flex Rec 25/.06 yielded the highest and lowest values for both parameters, respectively. Conclusions: Low‐tapered reciprocating instruments exhibit increased flexibility, higher time to fracture, and greater angles of rotation, coupled with reduced maximum bending loads and buckling strength compared to large‐tapered instruments. Nevertheless, low‐tapered systems also exhibit lower maximum torque to fracture and inferior cutting ability, contributing to a narrower apical canal enlargement that may compromise the penetration of irrigants in that region. [ABSTRACT FROM AUTHOR]

There is a growing appreciation of the role of aquaculture in improving food and nutrition security in Timor-Leste. The Timor-Leste government's National Aquaculture Development Strategy (NADS; 2012–30) envisions to increase domestic aquaculture production to 12,000 tons to achieve per capita fish consumption of 15 kg annually by 2030. However, aquaculture development is constrained by limited access to quality seed, feed, and improved technologies. WorldFish has been collaborating with the Ministry of Agriculture and Fisheries since 2015 to help realise the target. The objective was to present step-wise interventions – Genetically Improved Farmed Tilapia (GIFT) hatcheries establishment and monosex seed production and distribution; conduct of on-farm grow-out trials; training and capacity building; and extension, communication and marketing services - carried out, and demonstrate how availability, accessibility and consumption of fish could be increased sustainably in the subsistence farming systems of Timor-Leste. Farmers' participatory grow-out trials following better management practices (BMPs) were conducted in two phases from 2015 to 2023 across ten farmers clusters in four municipalities in inlands. The trials in Phase 1 tested GIFT stocked at 3 fingerlings/m2 using green water in ponds and fed with locally made plant-based feed. In Phase 2, trials tested GIFT stocked at 5 fingerings/m2 with high quality imported pelleted feed supplemented with local feed and green water. To facilitate scaling, local service providers, feed importers and fish market operators were trained to facilitate input supply and output marketing. In Phase-1, one existing public hatchery was upgraded for producing and supplying quality GIFT broodstock to private hatcheries and one private hatchery was established with public-private partnership (PPP) model. On-farm trials showed that farmers following BMPs and feeding with farm made feed achieved fish yield averaging 4.3 ± 1.5 t/ha/11 months production cycle. In Phase-2, PPP model hatcheries were established; nursery operators connected to each hatchery started nursing fry to fingerlings to local farmers. On-farm trials results managed by 169 farmers in 417 ponds during 2020–2022 showed fish yield of 12.4 ± 0.1 t/ha/ 6 month cycle with full BMPs , suggesting the viability of GIFT intensification across Timor-Leste. Continuous technical backstopping of public and private sectors, however, is crucial for scaling and sustainable intensification of aquaculture. GIFT aquaculture development model of Timor-Leste has potential for scaling across the country for reducing peoples' malnutrition and poverty. The model can also potentially be replicated to other small island nations of the Asia-Pacific region and beyond. [Display omitted] • Sustainable intensification of genetically improved farmed tilapia (GIFT) in the subsistence farming systems • On-farm trialsfollowed unique methods, fostering linkages across value chain for provisioning of input and services • Fish yield increased to 12.4 t/ha/cycle from 4.3 t/ha/cycle(∼300% increment) as a result of sustainable intensification • One-third (33%) of the tilapia produced by farmers contributed to the food and nutrition security of the rural communities • Economically, small-scale aquaculture has proven to be highly attractive, with a gross profit of 136% • The proven aquaculture development model has potential for scaling in Timor-Leste and the pacific island nations [ABSTRACT FROM AUTHOR]

In this work, the formation of the orthorhombic phase of ZrO 2 together with the minor monoclinic phase were elucidated by X-ray diffraction and transmission electron microscopy. Moreover, oxidized W can be responsible for the formation of oxygen vacancies in the ZrO 2 through oxygen scavenging. The ferroelectric properties of the W/ZrO 2 /W film capacitors were investigated through piezoresponse force microscopy (PFM) and polarization-voltage measurements. A second-order phase transition from the polar orthorhombic phase to the non-polar tetragonal phase was observed. Density functional theory calculations confirm our experimental results and propose that oxygen vacancies are responsible for the Curie–Weiss temperature of 130 °C, significantly lower than the theoretical value for the bulk. • Dielectric properties of ferroelectric orthorhombic ZrO 2 films were investigated. • An activation energy of 0.48 eV was estimated which can be associated to oxygen vacancies. • DFT calculations suggest that oxygen vacancies are responsible for lowering the Curie–Weiss temperature. [ABSTRACT FROM AUTHOR]