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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]

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]

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]

Background:Gastrointestinal stromal tumour (GIST) is mainly initialised by receptor tyrosine kinase gene mutations. Although the tyrosine kinase inhibitor imatinib mesylate considerably improved the outcome of patients, imatinib resistance still remains a major therapeutic challenge in GIST therapy. Herein we evaluated the clinical impact of microRNAs in imatinib-treated GISTs.Methods:The expression levels of microRNAs were quantified using microarray and RT-qPCR in GIST specimens from patients treated with neoadjuvant imatinib. The functional roles of miR-125a-5p and PTPN18 were evaluated in GIST cells. PTPN18 expression was quantified by western blotting in GIST samples.Results:We showed that overexpression levels of miR-125a-5p and miR-107 were associated with imatinib resistance in GIST specimens. Functionally, miR-125a-5p expression modulated imatinib sensitivity in GIST882 cells with a homozygous KIT mutation but not in GIST48 cells with double KIT mutations. Overexpression of miR-125a-5p suppressed PTPN18 expression, and silencing of PTPN18 expression increased cell viability in GIST882 cells upon imatinib treatment. PTPN18 protein levels were significantly lower in the imatinib-resistant GISTs and inversely correlated with miR-125a-5p. Furthermore, several microRNAs were significantly associated with metastasis, KIT mutational status and survival.Conclusions:Our findings highlight a novel functional role of miR-125a-5p on imatinib response through PTPN18 regulation in GIST. [ABSTRACT FROM AUTHOR]

Increased seed germination and seedling growth in soils infected with damping-off pathogen, Pythium ultimum, especially under saline conditions, are important goals in safflower breeding programs. Seeds of four safflower varieties were cultured on germination media moistened with solutions of NaCl containing 105 zoospores of the pathogen per ml. NaCl concentrations were adjusted to produce salinities 0, -10, -14 and -18 bar. Analysis of variance indicated that the interactive effects of salinity, cultivar and pathogen significantly altered seed germination and seedling dry weight. In the absence of P. ultimum, increasing salinity significantly reduced seedling dry weight, but in pathogen-inoculated media, different values were observed. In the absence of salinity, the germination rate of inoculated seeds was 16.3% lower than that of non-inoculated seeds, whereas in a saline bed, the pathogen increased seed germination about 3.1 %. This finding clearly indicates that sodium chloride can reduce the pathogenesis of P. ultimum on safflower seedlings. The results showed that the presence of NaCl in the environment prevented rotting effects of the pathogen on seeds but intensified the mortality effect on seedlings. The simultaneous effects of salinity and pathogen reduced the usual adverse effects of either factor when applied separately. Thus, depending on amount of NaCl and/or Pythium infection present, different varieties are recommended to achieve an acceptable establishment and production. [ABSTRACT FROM AUTHOR]

Experimental results presented in this article reveal the ability of nanoparticle-dispersed engine oil (nanolubricant) to deagglomerate metallic transfer films under extreme pressures. Specifically, metallic transfer films were formed and accumulated on the upper AISI 52100 ball in a four-ball tester, which resulted in negative wear—that is, weight gain—under Hertzian contact pressures ranging from 3.4 to 5.5 GPa. When molybdenum disulfide nanoparticles were dispersed in the engine oil, the AISI 52100 upper balls exhibited wear as expected. Scanning electron microscope examination of worn surfaces indicated large patches of metallic transfer films on the ring-shaped wear track of AISI 52100 upper balls tested with the engine oil. Such large patches of transfer films could not be found on the surfaces tested with the nanoparticle-modified engine oil. The experimental results and the mechanism of transfer film deagglomeration are discussed. [ABSTRACT FROM AUTHOR]

The concept of rhinogenic headaches remains a subject of much debate. While many authors have reported good results in treating these headaches with endoscopie sinus surgery, few have attempted to establish objective criteria for identifying the best surgical candidates. We conducted a study of 33 adults with rhinogenic headaches to determine if three elements of the history and/or five aspects of computed tomography (CT) would predict which patients might benefit from the minimally invasive sinus technique (MIST) as the primary treatment modality for their headaches. Postoperative follow-up interviews revealed that endoscopie surgery was widely successful, as 28 patients (84.8%) reported improvement. However, we were unable to find any statistically significant history or CT parameters that predicted surgical outcomes. [ABSTRACT FROM AUTHOR]

The diagnosis of low-grade B-cell lymphoma consistent with marginal-zone lymphoma has proven to be challenging when the disease involves the hard palate. The diagnosis is complicated by the nonspecific nature of the presenting symptoms and a difficult-to-differentiate histologic picture. We describe a case of low-grade B-cell lymphoma of the hard palate with a delayed presentation. We also compare the features of this case with the features of the small number of other such cases that have been reported in the literature. Finally, we review the etiology of low-grade B-cell lymphoma, we discuss its radiologic and pathologic features, and we briefly describe the treatment options. [ABSTRACT FROM AUTHOR]

Analysis of a planar periodic structure formed with two different microstrip line sections is presented. Closed-form expressions for the A BCD parameters of a structure with N unit cells are derived. The input-output characteristics of the structure are very similar to a bandpass/bandstop filter. Numerical results for the normalized output power provide good agreement with the measured data. [ABSTRACT FROM AUTHOR]