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Introduction: Green Revolution which occurred by introducing dwarfing genes into bread wheat varieties had a great impact on the global wheat production. Nevertheless, these genes decrease grain yield under rain-fed conditions. In general, semi-dwarf genes may not have any advantage in heat and drought stress conditions. In rain-fed conditions, the combination of Rht-D1b and Rht-B1b genes causes a decrease in the grain yield and coleoptile length. It should be noted that the genes Rht4, Rht5, Rht7, Rht8, Rht9, Rht12, Rht13 and Rht14, which are sensitive to gibberellic acid, do not affect coleoptile length. Materials and methods: In the present research, wild type genes which cause higher plant height were transferred from Roshan to Excalibur variety using backcrossing. Similarly, in the F3 generation of a cross between Roshan and Mahdavi, a semi-dwarf plant was observed. This plant was backcrossed with Roshan to have semi-dwarf isogenic lines of this cultivar. Development of isogenic lines for plant height in two genetic backgrounds made it possible to study the effect of the plant height on yield and yield components. Isogenic lines and their parents were evaluated in two successive years (2020-2021 and 2021-2022) under Sepidan rainfed conditions. Results and discussion: On average, plant height of Roshan and its semi-dwarf isogenic lines were 90.84 and 51.22 cm, respectively. Also, the average plant height of Excalibur and its tall isogenic line were 47.61 and 65.36 cm, respectively. Results showed that breeding for higher plant height had a positive and significant effect on wheat grain yield under rain-fed conditions. On average, tallness increased grain yield by 375.43 and 177.94 kg.ha in Roshan and Excalibur genetic backgrounds, respectively. In addition, the effect of plant height on yield components under rain-fed conditions was investigated. The findings of this research show that breeding for higher plant height indirectly increase grains number per spike and 1000 grain weight to improve grain yield. While, spikes number per meter square was not affected with plant height. Considering the high heritability of plant height and its significant correlation with grain yield, it is suggested that this trait be considered in breeding programs under rain-fed conditions. Conclusion: In the present research, it was found that tallness improve grains yield of bread wheat under rain-fed conditions via increasing grains number per spike. Two other yield components were also investigated and it was found that the plant height had no effect on spikes number per meter square. 1000-grains weight did not affected by plant height in the first year, although in the second year, the taller genotypes had higher 1000-grains weight. Considering that plant height has high heritability and response to selection, it is recommended to pay special attention to this trait in breeding programs for rain-fed conditions. It should be mentioned that as narrow sense heritability of plant height is very high, selection for this trait based on single plant is very effective. Consequently, selection for plant height in backcrossing and pedigree breeding methods could be extremely successful. [ABSTRACT FROM AUTHOR]

Metasurface coatings on a free-standing SiN thin film membrane are fabricated on a Si substrate using masked lithography and CMOS-compatible surface micromachining. The result is a band-limited absorber for the mid-IR, which is part of a microstructure that is attached to the substrate by long and slender suspension beams to provide thermal isolation. As a residual of the fabrication, the regular pattern of sub-wavelength unit cells of 2.6 μm side length, which defines the metasurface, is interrupted by an equally regular array of sub-wavelength holes of 1–2 μm diameter and at 7.8–15.6 μm of pitch. This array of holes is essential for enabling access of the etchant and attack of the underlying layer during fabrication, which ultimately results in the sacrificial release of the membrane from the underlying substrate. As the plasmonic responses of the two patterns interfere, a maximum is imposed on the hole diameter and a minimum on the hole-to-hole pitch. However, the hole diameter should be sufficiently large to allow access of the etchant, while the maximum spacing between holes is set by the limited selectivity of the different materials to the etchant during sacrificial release. The effect of the parasitic hole pattern on the spectral absorption of a metasurface design is analyzed by simulations of the responses of combined holes–metasurface structures. Arrays of 300 × 180 μm2 Al-Al2O3-Al MIM structures are mask-fabricated on suspended SiN beams. The results show that the effect of the array of holes can be disregarded for a hole-to-hole pitch larger than 6 times the side length of the metamaterial until cell, while the diameter of the hole should remain smaller than about 1.5 μm, and their alignment is critical. [ABSTRACT FROM AUTHOR]

This work investigates the existence and uniqueness of solutions for a coupled system of fractional differential equations with three-point generalized fractional integral boundary conditions within generalized proportional fractional derivatives of the Riemann-Liouville type. By using the Schauder and Banach fixed point theorems, we study the existence and uniqueness of solutions for the aforesaid system. Finally, we present an example to validate our theoretical outcomes. [ABSTRACT FROM AUTHOR]

More than 200 iron deposits with about 4 billion tons of iron ore have been discovered in Iran. Major iron oxide districts comprise the Bafq-Posht-e-Badam back arc district in Central Iranian microcontinent, the Ac Kahoor and Hormoz districts in the Zagros mountain range, the Gol-e-Gohar and Hamekasi deposits in the Sanandaj–Sirjan magmatic–metamorphic zone and also the Sangan deposit east of Central Iran. Several smaller iron ore deposits are distributed in the Alborz–Azarbaijan magmatic belt. There is a significant correspondence between the distribution of these deposits and main suture zones in the Iran plate composite. Stratiform iron deposits with a volcano-sedimentary origin are common features of the rifting phases of the future Prototethys and Neotethys oceans. Kiruna-type iron oxide deposits of the Zanjan area, and Fe skarn and iron oxide–copper–gold deposits in the Khaf–Bardaskan–Kashmar district are associated with subduction of Neotethys Ocean. Kiruna-type deposits within the Kashmar–Kerman magmatic arc are related to the Prototethys. Different geotectonic scenarios and their evolution explain the distribution patterns of most of the Fe and Fe–Mn deposits in Iran. Stratiform volcano-sedimentary Fe- and Fe–Mn deposits are related to the rift basin, and other types of Fe and Fe–Mn deposits such as the Kiruna-type deposits, skarn and iron oxide–copper–gold deposits in Iran are related to basin closure and plate collision. Magmatism in the subduction zone produced the magmatic and hydrothermal fluids, which caused Fe and Fe–Mn mineralisation in Central Iran microcontinent, Sanandaj–Sirjan magmatic–metamorphic zone, Alborz–Azarbaijan magmatic belt, east of Central Iran and the Lut blocks. The Central Iran microcontinent (Khaf–Bardaskan–Kashmar district), east of Central Iran, the Sanandaj–Sirjan zone and the Alborz–Azarbaijan belts are the most prospective districts for Fe and Fe–Mn exploration. Based on the age data on the studied deposits, favourable time periods for the largest Fe and Fe–Mn mineralising events in Iran were the Neoproterozoic–lower Cambrian (volcano-sedimentary and Kiruna-type deposits), upper Paleozoic–lower Mesozoic (volcano-sedimentary iron deposits) and Cenozoic (Kiruna type, iron oxide–copper–gold deposits and especially skarn deposits). [ABSTRACT FROM PUBLISHER]

Introduction: WHO HCV elimination targets include increased diagnosis (90%) and treatment uptake (80%) by 2030. This study evaluated the impact of a microelimination intervention among people who use drugs in Rafsanjan, Iran. Methods: This observational study is evaluating an intervention to scale-up of direct-acting antiviral (DAA) treatment to reduce HCV RNA prevalence (i.e. microelimination) in Rafsanjan, Iran (population 200, 000). Between October 2019 and April 2021 (18 months), participants are recruited from one prison, 35 OAT clinics, four residential addiction treatment centers, one HIV clinic, and a newly established HCV clinic (integrated within existing HIV services). All people attending the study sites are invited to participate. Intervention entails on-site rapid HCV antibody testing, venepuncture sampling for HCV RNA testing (if antibody positive), and DAA dispensing for people with HCV. The uptake of HCV diagnosis and treatment and HCV RNA prevalence are compared at baseline and 12 months post-intervention. Results: During October 2019-March 2020, 3, 648 people were enrolled. Median age was 40 years (IQR 33-48), majority were male (95%), and reported a history of drug use (injecting and/or non-injecting, 89%). Overall, 6% reported a history of injecting drug use (IDU); of whom, 8% reported injecting in the past year. HCV antibody prevalence was 7% (241/3, 648), including 58% (119/206), 4% (108/2, 920), and 3% (14/414) among people with a history of IDU, non-injecting drug use, and no drug use, respectively. Among those with detectable HCV RNA (181/241), 97% initiated DAA therapy, including 98% (94/96), 96% (71/74), and 100% (11/11) among people with a history of IDU, non-injecting drug use, and no drug use, respectively. Conclusion: This initiative developed a multi-stakeholder collaboration and implemented Rafsanjan’s first HCV program within six months. The preliminary findings, including feasibility of recruitment model and high treatment uptake, are encouraging with regard to HCV micro-elimination. [ABSTRACT FROM AUTHOR]