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BackgroundCorneal ulcers are a common cause of blindness in low-income and middle-income countries, usually resulting from traumatic corneal abrasions during agricultural work. Antimicrobial prophylaxis of corneal abrasions can help prevent corneal ulcers, but delays in the initiation of therapy are frequent. We aimed to assess whether a community-based programme for corneal ulcer prevention would reduce the incidence of corneal ulceration.MethodsA cluster-randomised trial was performed in village development committees (VDCs) in Nepal. VDCs in the catchment area of Bharatpur Eye Hospital, Nepal with less than 15 000 people were eligible for inclusion. We randomly assigned (1:1) VDCs to either an intervention group or a control group. In the intervention VDCs, existing female community health volunteers (FCHVs) were trained to diagnose corneal abrasions and provide a 3-day course of ophthalmic antimicrobials to their patients. In the control VDCs, FCHVs did not provide this intervention. Participants were not masked given the nature of the intervention. Both groups were followed up for 3 years for photographic evidence of corneal ulceration. The primary outcome was the incidence of corneal ulceration, determined by masked assessment of corneal photographs. The analysis was by intention to treat. This trial is registered with ClinicalTrials.gov, NCT01969786.FindingsWe assessed 112 VDCs, of which 24 were enrolled. The study was performed between Feb 4, 2014, and Oct 20, 2017. 12 VDCs were randomly assigned to the intervention group and 12 to the control group. 252 539 individuals were included in the study (130 579 in the intervention group and 121 960 in the control group). FCHVs diagnosed and provided antimicrobials for 4777 corneal abrasions. The census identified 289 corneal ulcers among 246 893 person-years in the intervention group (incidence 1·21 cases [95% CI 0·85-1·74] per 1000 person-years) and 262 corneal ulcers among 239 170 person-years in the control group (incidence 1·18 cases [0·82-1·70] per 1000 person-years; incidence rate ratio 1·03 [95% CI 0·63-1·67]; p=0·93). Medication allergy was self-reported in 0·2% of participants.InterpretationWe did not detect a reduction in the incidence of corneal ulceration during the first 3 years of a community-based corneal ulcer prevention programme. Further study might be warranted in more rural areas where basic eye care facilities are not available.FundingNational Eye Institute.

Community health workers (CHWs) are essential to primary health care systems and are a cost-effective strategy to achieve the Sustainable Development Goals (SDGs). Nepal is strongly committed to universal health coverage and the SDGs. In 2017, the Nepal Ministry of Health and Population partnered with the nongovernmental organization Nyaya Health Nepal to pilot a program aligned with the 2018 World Health Organization guidelines for CHWs. The program includes CHWs who: (1) receive regular financial compensation; (2) meet a minimum education level; (3) are well supervised; (4) are continuously trained; (5) are integrated into local primary health care systems; (6) use mobile health tools; (7) have consistent supply chain; (8) live in the communities they serve; and (9) provide service without point-of-care user fees. The pilot model has previously demonstrated improved institutional birth rate, antenatal care completion, and postpartum contraception utilization. Here, we performed a retrospective costing analysis from July 16, 2017 to July 15, 2018, in a catchment area population of 60,000. The average per capita annual cost is US$3.05 (range: US$1.94 to US$4.70 across 24 villages) of which 74% is personnel cost. Service delivery and administrative costs and per beneficiary costs for all services are also described. To address the current discourse among Nepali policy makers at the local and federal levels, we also present 3 alternative implementation scenarios that policy makers may consider. Given the Government of Nepal's commitment to increase health care spending (US$51.00 per capita) to 7.0% of the 2030 gross domestic product, paired with recent health care systems decentralization leading to expanded fiscal space in municipalities, this CHW program provides a feasible opportunity to make progress toward achieving universal health coverage and the health-related SDGs. This costing analysis offers insights and practical considerations for policy makers and locally elected officials for deploying a CHW cadre as a mechanism to achieve the SDG targets.

In recent years, narrow band gap layered materials were reported as an interesting candidate for energy efficient devices. Here, we chose BiTeI, a layered material that has significant Rashba spin splitting, for charge modification with the purpose of exploring the electronic, magnetic and topological properties. Chemical doping with an Mn atom is done to the Te site in BiTeI. On the basis of density functional theory calculations, we found that the parent material BiTeI is a semiconductor with an indirect band gap of ∼0.46 eV within full-relativistic mode. The orbital contributions around the Fermi level are found to be mainly from the Bi-6p, I-5p and Te-5p states in the electronic structure. Upon chemical doping by Mn to Bi, Te and I separately, doping to the Te site is energetically favorable with a ferromagnetic ground state and a semimetallic behaviour. The doped material, i.e., Bi2TeMnI2, is found to be a magnetic Weyl semimetal with six Weyl points close to the Fermi level (around 100 meV in the conduction region). Our calculations suggest Bi2TeMnI2 as a probable candidate of a Weyl semimetal. The emergence of Weyl points gives rise to a large intrinsic anomalous Hall conductivity of up to ∼750 Ω−1 cm−1. The calculated negative value of formation energy (−0.233 eV) and the positive phonon frequency suggests Bi2TeMnI2 to be thermodynamically favorable and dynamically stable. This work deserves a transport experiment to confirm our claim, which might provide insights towards discovering new quantum materials suitable for high-speed electronics, spintronics and quantum computing. [ABSTRACT FROM AUTHOR]

Interplay of magnetism and electronic band topology in unconventional magnets enables the creation and fine control of novel electronic phenomena. In this work, we use scanning tunneling microscopy and spectroscopy to study thin films of a prototypical kagome magnet Fe3Sn2. Our experiments reveal an unusually large number of densely-spaced spectroscopic features straddling the Fermi level. These are consistent with signatures of low-energy Weyl fermions and associated topological Fermi arc surface states predicted by theory. By measuring their response as a function of magnetic field, we discover a pronounced evolution in energy tied to the magnetization direction. Electron scattering and interference imaging further demonstrates the tunable nature of a subset of related electronic states. Our experiments provide a direct visualization of how in-situ spin reorientation drives changes in the electronic density of states of the Weyl fermion band structure. Combined with previous reports of massive Dirac fermions, flat bands, and electronic nematicity, our work establishes Fe3Sn2 as an interesting platform that harbors an extraordinarily wide array of topological and correlated electron phenomena. [ABSTRACT FROM AUTHOR]

In recent years, narrow band gap layered materials were reported as an interesting candidate for energy efficient devices. Here, we chose BiTeI, a layered material that has significant Rashba spin splitting, for charge modification with the purpose of exploring the electronic, magnetic and topological properties. Chemical doping with an Mn atom is done to the Te site in BiTeI. On the basis of density functional theory calculations, we found that the parent material BiTeI is a semiconductor with an indirect band gap of ∼0.46 eV within full-relativistic mode. The orbital contributions around the Fermi level are found to be mainly from the Bi-6p, I-5p and Te-5p states in the electronic structure. Upon chemical doping by Mn to Bi, Te and I separately, doping to the Te site is energetically favorable with a ferromagnetic ground state and a semimetallic behaviour. The doped material, i.e. , Bi 2 TeMnI 2 , is found to be a magnetic Weyl semimetal with six Weyl points close to the Fermi level (around 100 meV in the conduction region). Our calculations suggest Bi 2 TeMnI 2 as a probable candidate of a Weyl semimetal. The emergence of Weyl points gives rise to a large intrinsic anomalous Hall conductivity of up to ∼750 Ω -1 cm -1 . The calculated negative value of formation energy (-0.233 eV) and the positive phonon frequency suggests Bi 2 TeMnI 2 to be thermodynamically favorable and dynamically stable. This work deserves a transport experiment to confirm our claim, which might provide insights towards discovering new quantum materials suitable for high-speed electronics, spintronics and quantum computing.