Hydrothermal Valorization of Biosugars with Heterogeneous Catalysts: Advances, Catalyst Deactivation, Mitigation Strategies and Perspectives.

Sustainable production of valuable biochemicals and biofuels from lignocellulosic biomass necessitates the development of durable and high-performance catalysts. To assist the next stage catalyst design for hydrothermal treatment of biosugars, this paper provides a critical review of (1) recent advances in biosugar hydrothermal valorization using heterogeneous catalysts, (2) the deactivation process of catalysts based on recycling tests of representative biosugar hydrothermal treatments, (3) state-of-the-art understandings of the deactivation mechanisms of heterogeneous catalysts, and (4) strategies of preparing durable catalysts and the regeneration of deactivated catalysts. Based on the review, challenges and perspectives are proposed. Some remarkable achievements in heterogeneous catalysis of biosugars are highlighted. The understanding of catalyst durability needs to be further increased based on full examination of the catalytic performance based on the conversion of substrates, the yield and selectivity of products. Further, a full examination of the physiochemical changes based on multiple characterization techniques is required to illuminate the relationships between treatment variables and catalyst durability. Collectively, a clear understanding of the relationships between chemical reaction pathways, treatment variables and the physiochemistry of catalysts is encouraged to be gained to advise the development of heterogeneous catalysts for long-term and efficient hydrothermal upgrading of biosugars.

Effects of copper on chemical kinetics and brown carbon formation in the aqueous ˙OH oxidation of phenolic compounds.

Many phenolic compounds (PhCs) in biomass burning and fossil fuel combustion emissions can partition into atmospheric aqueous phases (e.g., cloud/fog water and aqueous aerosols) and undergo reactions to form secondary organic aerosols (SOAs) and brown carbon (BrC). Redox-active transition metals, particularly Fe and Cu, are ubiquitous species in atmospheric aqueous phases known to participate in Fenton/Fenton-like chemistry as a source of aqueous ˙OH. However, even though the concentrations of water-soluble Cu are close to those of water-soluble Fe in atmospheric aqueous phases in some areas, unlike Fe, the effects that Cu have on SOA and BrC formation in atmospheric aqueous phases have scarcely been studied and remain poorly understood. We investigated the effects of Cu(II) on PhC reaction rates and BrC formation during the aqueous oxidation of four PhCs (guaiacol, catechol, syringol, and vanillin) by ˙OH generated from Fenton-like chemistry under different pH conditions. While the PhCs reacted when both H2O2 and Cu(II) were present in the absence (i.e., dark oxidation) and presence (i.e., photooxidation) of light, the reaction rates were at least one order of magnitude higher during photooxidation. Higher PhC reaction rates were measured at higher pH during both dark oxidation and photooxidation as a result of higher ˙OH concentrations produced by Fenton-like chemistry. Only water-soluble BrC was formed during dark oxidation and photooxidation when Cu(II) was present. Mass absorption coefficients (103 to 104 cm2 g-1) comparable to those of biomass burning BrC were measured during dark oxidation and photooxidation when Cu(II) was present. Light absorption was enhanced at higher pH during dark oxidation and photooxidation, which indicated that higher quantities and/or more absorbing BrC chromophores were formed at higher pH. The effects that Cu(II) had on the PhC reaction rates and the composition of SOAs and BrC formed depended on the PhC base structure (i.e., benzenediol vs. methoxyphenol). Overall, these results show how aqueous reactions involving Cu(II), H2O2, and PhCs can be an efficient source of daytime and nighttime water-soluble BrC and SOAs, which can have significant implications for how the atmospheric fates of PhCs are modeled for areas with substantial concentrations of water-soluble Cu in highly to moderately acidic cloud/fog water and aqueous aerosols.

Effects of an online mindfulness-based program for parents of children with attention deficit/hyperactivity disorder: a pilot, mixed methods study.

Objectives: Online mindfulness-based program (MBP) for parents and families especially in clinical population is limited. Engagement and significant dropout are major issues in MBP implementation. This pilot study examined the effects of an online mindfulness-based program (MBP) on parents of children with Attention Deficit/Hyperactivity Disorder (ADHD). Methods: A mixed methods study was applied to evaluate the effects of the MBP. A total of 43 parents were recruited and were randomly assigned into intervention group and waitlist control group. The online MBP lasted for 28 days, including 20 psychoeducation videos, homework audio guidance, and four instructor-led online group meetings. Purposive sampling was used to recruit parents who completed the program to share their experiences and suggestions for improving the program in semi-structured online interviews. Results: Quantitative data showed that participants from the online MBP reported a medium to large effect on the reduction of child ADHD symptoms. In semi-structured interviews, participants reported positive experiences in their help seeking intention, and personal changes, such as emotion regulation and quality attention to their children. Participants further made suggestions for improvement. Conclusions: The effect of online MBP is promising, and the program should be conducted. A large scale randomized controlled trial should be conducted to investigate the effects of MBP in clinical populations. Clinical trial registration: ClinicalTrials.gov NCT05480423.

Forging a sustainable sky: Unveiling the pillars of aviation e-fuel production for carbon emission circularity.

In 2021, airplanes consumed nearly 250 million tons of fuel, equivalent to almost 10.75 exajoules. Anticipated growth in air travel suggests increasing fuel consumption. In January 2022, demand surged by 82.3%, as per the International Air Transport Association. In tackling aviation emissions, governments promote synthetic e-fuels to cut carbon. Sustainable aviation fuel (SAF) production increased from 1.9 million to 15.8 million gallons in six years. Although cost of kerosene produced with carbon dioxide from direct air capture (DAC) is several times higher than the cost of conventional jet fuel, its projected production cost is expected to decrease from $104-$124/MWh in 2030 to $60-$69/MWh in 2050. Advances in DAC technology, decreasing cost of renewable electricity, and improvements in FT technology are reasons to believe that the cost of e-kerosene will decline. This review describes major e-kerosene synthesis methods, incorporating DAC, hydrogen from water electrolysis, and hydrocarbon synthesis via the Fischer-Tropsch process. The importance of integrating e-fuel production with renewable energy sources and sustainable feedstock utilization cannot be overstated in achieving carbon emission circularity. The paper explores the concept of power-to-liquid (PtL) pathways, where renewable energy is used to convert renewable feedstocks into e-fuels. In addition to these technological improvements, carbon pricing, government subsidies, and public procurement are several policy initiatives that could help to reduce the cost of e-kerosene. Our review provides a comprehensive guide to the production pathways, technological advancements, and carbon emission circularity aspects of aviation e-fuels. It will provide a valuable resource for researchers, policymakers, industry stakeholders, and the general public interested in transitioning to a sustainable aviation industry.

One-pot redox cascade paired electrosynthesis of gamma-butyrolactone from furoic acid.

The catalytic valorisation of biomass to afford synthetically useful small molecules is essential for sustainable biorefinery processes. Herein, we present a mild cascaded electrochemical protocol for converting furoic acid, a common biomass-derived feedstock, into a versatile platform chemical, gamma-butyrolactone. In the platinum(+)|nickel(-) electrode paired undivided cell, furoic acid is electrochemically oxidised with 84.2% selectivity to 2(5H)-furanone, the olefin of which is then hydrogenated to yield gamma-butyrolactone with 98.5% selectivity. The final gamma-butyrolactone yield is 69.1% with 38.3% Faradaic efficiency and 80.1% carbon balance when the reaction is performed with 100 mM furoic acid at 80 °C at +2.0 VAg/AgCl. Mechanistic investigation revealed the critical temperature and electrolyte pH conditions that maximise the production and protection of the key intermediate, furan radical, promoting its transition to 2(5H)-furanone rather than self-polymerising. The reaction is scalable, as 2.1 g of 98.1% pure gamma-butyrolactone is isolated through a simple solvent extraction.

Carbocation Mechanism Revelation of Molecular Iodine-Mediated Dehydrogenative Aromatization of Substituted Cyclic Ketones to Phenols.

Dehydrogenative aromatization (DA) of cyclic ketones is central to the development of functionalized aromatic precursors and hydrogen transfer-related technologies. Traditional DA strategies require precious metals with oxidants and are typically performed at high temperatures (100-150 °C) to overcome the high energy barrier of aliphatic C-H bond activation. Recently, a mild alternative approach based on I2 has been proposed to realize DA on substituted unsaturated cyclic ketones under ambient conditions. However, depending on the solvent, the product selectivity may vary between phenol ether and phenol, and the reaction mechanisms remain unclear. Herein, based on time-resolved proton nuclear magnetic resonance, DFT calculation, and mass spectrometric analyses, we established a unified mechanism to account for the product distribution. Through substrate scope and desorption electrospray ionization-mass spectrometry, we discovered the formation of a carbocation, which has been overlooked in previous studies. An expanded substrate scope study coupled with spectroscopic observation provided strong evidence to elucidate the formation mechanism and the location of the carbocation. With a renewed understanding of the mechanism, we achieved a phenolic product yield of 17-96% while controlling the selectivity. Moreover, some reactants could undergo DA in H2O, achieving 95-96% yield at below water-boiling temperature.

Proteins that carry dual targeting signals can act as tethers between peroxisomes and partner organelles.

Peroxisomes are organelles with crucial functions in oxidative metabolism. To correctly target to peroxisomes, proteins require specialized targeting signals. A mystery in the field is the sorting of proteins that carry a targeting signal for peroxisomes and as well as for other organelles, such as mitochondria or the endoplasmic reticulum (ER). Exploring several of these proteins in fungal model systems, we observed that they can act as tethers bridging organelles together to create contact sites. We show that in Saccharomyces cerevisiae this mode of tethering involves the peroxisome import machinery, the ER-mitochondria encounter structure (ERMES) at mitochondria and the guided entry of tail-anchored proteins (GET) pathway at the ER. Our findings introduce a previously unexplored concept of how dual affinity proteins can regulate organelle attachment and communication.

Optimizing electroactive membrane performance for microalgae harvesting: A response surface methodology study of membrane formulation and operating parameters for electro filtration.

Developing electroactive membranes for filtration has gained importance owing to their effectiveness in mitigating the long-lasting issue of fouling faced with traditional membranes. Here, we developed thin electroactive metallic films on to stainless steel mesh (SSM) using electrodeposition method and evaluated their performance for microalgae harvesting via electro filtration. The effect of electrodeposition parameters on membrane formulation and operating parameters for electro filtration, both in continuous and intermittent modes, were evaluated and optimum values were obtained using response surface methodology (RSM). The optimal combination of electrodeposition parameters is 1000 µA/cm2 and 5 min for deposition current density and time, respectively. Whereas the electric field strength of 20 V/mm with an application time of 1 min is suggested to be the optimal combination of electro filtration parameters for maximized flux recovery and corresponding experimental rejection efficiency of more than 90%. Overall, this research contributes to a better understanding of the parameters governing electro-filtration and offers insights for improving the performance of membrane-based microalgae harvesting systems.

Degradation of organic UV filters in the water environment: A concise review on the mechanism, toxicity, and technologies.

Organic ultraviolet filters (OUVFs) have been used globally for the past 20 years. Given that OUVFs can be quickly released from sunscreens applied on human skins, they have been frequently detected in aquatic environments and organisms. Some byproducts of OUVFs might be more recalcitrant and toxic than their parent compounds. To further assess the toxicity and potential risk of OUVFs' byproducts, it is necessary to determine the fate of OUVFs and identify their transformation products. This review summarizes and analyzes pertinent literature and reports in the field of OUVFs research. These published research works majorly focus on the degradation mechanisms of OUVFs in aquatic environments, their intermediates/byproducts, and chlorination reaction. Photodegradation (direct photolysis, self-sensitive photolysis and indirect photolysis) and biodegradation are the main transformation pathways of OUVFs through natural degradation. To remove residual OUVFs' pollutants from aqueous environments, novel physicochemical and biological approaches have been developed in recent years. Advanced oxidation, ultrasound, and bio-based technologies have been proven to eliminate OUVFs from wastewaters. In addition, the disinfection mechanism and the byproducts (DBPs) of various OUVFs in swimming pools are discussed in this review. Besides, knowledge gaps and future research directions in this field of study are also mentioned.

Piezocatalysis for Chemical-Mechanical Polishing of SiC: Dual Roles of t-BaTiO3 as a Piezocatalyst and an Abrasive.

Chemical mechanical polishing (CMP) offers a promising pathway to smooth third-generation semiconductors. However, it is still a challenge to reduce the use of additional oxidants or/and energy in current CMP processes. Here, a new and green atomically smoothing method: Piezocatalytic-CMP (Piezo-CMP) is reported. Investigation shows that the Piezo-CMP based on tetragonal BaTiO3 (t-BT) can polish the rough surface of a reaction sintering SiC (RS-SiC) to the ultra-smooth surface with an average surface roughness (Ra) of 0.45 nm and the rough surface of a single-crystal 4H-SiC to the atomic planarization Si and C surfaces with Ra of 0.120 and 0.157 nm, respectively. In these processes, t-BT plays a dual role of piezocatalyst and abrasive. That is, it piezo-catalytically generates in-situ active oxygen species to selectively oxidize protruding sites of SiC surface, yielding soft SiO2, and subsequently, it acts as a usual abrasive to mechanically remove these SiO2. This mechanism is further confirmed by density functional theory (DFT) calculation and molecular simulation. In this process, piezocatalytic oxidation is driven only by the original pressure and friction force of a conventional polishing process, thus, the piezo-CMP process do not require any additional oxidant and energy, being a green and effective polishing method.

Amorphous RuO2 Catalyst for Medium Size Carboxylic Acid to Alkane Dimer Selective Kolbe Electrolysis in an Aqueous Environment.

The catalytic transformation of biomass-derived volatile carboxylic acids in an aqueous environment is crucial to developing a sustainable biorefinery. To date, Kolbe electrolysis remains arguably the most effective means to convert energy-diluted aliphatic carboxylic acids (carboxylate) to alkane for biofuel production. This paper reports the use of a structurally disordered amorphous RuO2 (a-RuO2 ) that is synthesized facilely in a hydrothermal method. The a-RuO2 is highly effective towards electrocatalytic oxidative decarboxylation of hexanoic acid and is able to produce the Kolbe product, decane, with a yield 5.4 times greater than that of commercial RuO2 . A systematic study of the reaction temperature, current intensity, and electrolyte concentration reveals the enhanced Kolbe product yield is attributable to the more efficient oxidation of the carboxylate anions for the alkane dimer formation. Our work showcases a new design idea for establishing an efficient electrocatalysts for decarboxylation coupling reaction, providing a new electrocatalyst candidate for Kolbe electrolysis.

Rural Community Pharmacists' Perceptions of Implementing Mental Health Interventions to Reach Underserved Populations.

Mental illness and suicide are significant public health problems. Limited resources put individuals at greater risk, particularly in rural areas with fewer health providers. Community pharmacists are the most accessible health professionals in rural communities and are interested in addressing mental health concerns. Research is limited on how to implement mental health interventions in community pharmacy settings. The objectives of this study were to assess community pharmacists' perceptions of mental health interventions and barriers and facilitators to implementation and prioritize interventions to be pilot tested. Qualitative interviews were conducted with community pharmacists (N=17). Interviews focused on perceptions of mental health interventions in pharmacy settings. Data were analyzed using template analysis. A stakeholder meeting reviewed data and prioritized interventions to be pilot tested. Pharmacists viewed implementing mental health interventions positively. Barriers included lack of mental health knowledge, time, diagnosis, and concerns about workflow. Facilitators included accessible settings, knowing the community, and seeing patients frequently. The most common needs for implementation were education and payment. Pharmacists preferred progress monitoring in collaboration with a prescriber and mental health first aid training. Further research is needed to gather feedback from prescribers to inform implementation.

Lineage switching of the cellular distribution of BRAFV600E in multisystem Langerhans cell histiocytosis.

Most children with high-risk Langerhans cell histiocytosis (LCH) have BRAFV600E mutation. BRAFV600E alleles are detectable in myeloid mononuclear cells at diagnosis but it is not known if the cellular distribution of mutation evolves over time. Here, the profiles of 16 patients with high-risk disease were analyzed. Two received conventional salvage chemotherapy, 4 patients on inhibitors were tracked at intervals of 3 to 6 years, and 10 patients, also given inhibitors, were analyzed more than 2 years after diagnosis. In contrast to the patients responding to salvage chemotherapy who completely cleared BRAFV600E within 6 months, children who received inhibitors maintained high BRAFV600E alleles in their blood. At diagnosis, mutation was detected predominantly in monocytes and myeloid dendritic cells. With time, mutation switched to the T-cell compartment, which accounted for most of the mutational burden in peripheral blood mononuclear cells, more than 2 years from diagnosis (median, 85.4%; range, 44.5%-100%). The highest level of mutation occurred in naïve CD4+ T cells (median, 51.2%; range, 3.8%-93.5%). This study reveals an unexpected lineage switch of BRAFV600E mutation in high-risk LCH, which may influence monitoring strategies for the potential withdrawal of inhibitor treatment and has new implications for the pathogenesis of neurodegeneration, which occurred in 4 patients.

Effects of students' perception of teachers' ethnic-racial socialization on students' ethnic identity and mental health in rural China's schools.

Introduction: Using students in the Liangshan Yi autonomous prefectures of southwestern China (n = 585; 13-15 years old), we examined (i) the effects of students' perception of their teachers' ethnic-racial socialization on their ethnic identity and mental health outcomes of depressive and stress symptoms; (ii) the effects of students' ethnic identity on their depressive and stress symptoms; (iii) the differential associations among these factors in Yi ethnic minority versus Han cultural majority students. Methods: We conducted a cross-sectional survey and used multistage sampling to collect the information. Chinese-validated standardized measures were used: the Patient Health Questionaires-9, Children's Revised Impact of Event Scale-8, Multigroup Ethnic Identity Measure, Cultural Socialization Scale, and Teachers' Attitude on Adoption of Cultural Diversity Scale. Multigroup confirmatory factor analysis and multigroup structural equation modeling were employed. Results: Comparing the findings in Yi and Han students, their perception of teachers' ethnic-racial socialization had dissimilar effects on their ethnic identity and mental health outcomes. Three key findings comparing the differences between Yi and Han students were as follows: (i) students' perception of their teachers' multicultural socialization practices positively affected the ethnic identity of both Yi and Han young people; however, their perception of their teachers' socializing them to their own cultures did not exert any effect; (ii) students' perception of teachers' multicultural socialization practices had different mental health effects on Yi versus Han students; and (iii) ethnic identity affected the mental health of Yi ethnic minority students only. Conclusion: The findings underscore the importance of teachers' multicultural socialization in the ethnic identity development of both Yi ethnic minority and Han majority students. Ethnic identity serves as a linking variable bridging perceived teachers' multicultural socialization practices and mental health in Yi ethnic minority students but not among the Han cultural majority youths. Research, practice, and policy implications relevant to the global context are also discussed.

Posterior Ankle Impingement Syndrome Clinical Features Are Not Associated With Imaging Findings in Elite Ballet Dancers and Athletes.

OBJECTIVE: To assess the association between clinical features and magnetic resonance imaging (MRI) findings in posterior ankle impingement syndrome (PAIS) and to compare the prevalence of imaging findings between participants with and without a clinical diagnosis of PAIS. DESIGN: Case-control study. SETTING: Elite ballet and sport. PARTICIPANTS: Eighty-two male (54%) and female participants comprising ballet dancers (n = 43), cricket fast bowlers (n = 24), and football (soccer) players (n = 15). INDEPENDENT VARIABLES: Clinical: posterior ankle pain on body chart, passive plantarflexion pain provocation test. Patient-reported outcome measures: Oslo Sports Trauma Research Center Overuse Injury Questionnaire, Foot and Ankle Ability Measure Sports subscale. MAIN OUTCOME MEASURES: Imaging findings including posterior ankle bone marrow edema, os trigonum (± bone marrow edema, and increased signal at synchondrosis), Stieda process (± bone marrow edema), talocrural and subtalar joint effusion-synovitis size, flexor hallucis longus tendinopathy, and tenosynovitis identified as present or absent on 3.0-Tesla MRI. RESULTS: Imaging findings were not associated with posterior ankle pain or a positive ankle plantarflexion pain provocation test. Imaging findings were not associated with patient-reported outcome measures. Imaging findings did not differ between PAIS-positive and PAIS-negative groups. Os trigonum and Stieda process were prevalent despite clinical status. CONCLUSIONS: The lack of association between imaging findings and clinical features questions the role of imaging in PAIS. Clinicians should rely primarily on clinical assessment in the diagnosis and management of patients with PAIS.

COVID-19 vaccine hesitancy and resistance in an urban Chinese population of Hong Kong: a cross-sectional study.

Vaccine hesitancy against COVID-19 is prevalent. This study aimed to identify the factors associated with COVID-19 vaccination compliance among adults in Hong Kong. An online survey was conducted during an early stage of community-based COVID-19 vaccination campaign in Hong Kong. The questionnaire consisted of vaccine status, sociodemographic information, risk perception of being infected by COVID-19, and exposure to confirmed COVID cases, as well as items on sleep and mental health. The association between these variables and vaccine hesitancy was analyzed. Among the 883 participants (67.5% females, 54.5% aged 18-39), 30.6% had low vaccine hesitancy, 27.4% had high vaccine hesitancy, and 27.5% had vaccine rejection. The likelihood of having high vaccine hesitancy was higher among young (adjusted odds ratio [aOR] = 2.99; 95% confidence interval [CI]: 1.23-7.30) and middle-aged respondents (aOR = 2.99; 95% CI: 1.07-5.47) than among old respondents. Moreover, those who were married (aOR = 0.51; 95% CI: 0.29-0.88), had a full-time job (aOR = 0.55; 95% CI: 0.29-0.88), and had a greater confidence in the government (aOR = 0.68; 95% CI: 0.54-0.86) were less likely to exhibit vaccine hesitancy. Our findings showed that the prevalence of vaccine hesitancy and vaccine resistance were high. Policy makers need specific strategies to target those who may have a high risk of vaccine hesitancy and resistance.

Highly dispersed Ag and g-C3N4 quantum dots co-decorated 3D hierarchical Fe3O4 hollow microspheres for solar-light-driven pharmaceutical pollutants degradation in natural water matrix.

The efficient removal of pharmaceutical pollutants presents a great challenge for the conventional sewage treatment system. Herein, we document the nanosheets assembled 3D hierarchical Fe3O4 hollow microspheres co-modified by Ag and g-C3N4 quantum dots (Ag/CNQDs@Fe3O4) for efficient degradation of two classic anticancer drugs, i.e., capecitabine (CAP) and 5-fluorouracil (5-FLU) under visible light in 1 h. Benefiting from the unique hierarchically hollow structure, the intrinsic strengths of each component and their interactions, synergistic reinforcing mechanism is constructed, furnishing more accessible reactive places, promoting the diffusion of pollutants/oxidants, improving charge separation ability, and raising light utilization rate. Consequently, Ag/CNQDs@Fe3O4 can not only show superior photocatalytic properties, but also greatly boost PMS activation to yield sufficient oxidative radicals. More notably, the studied system also features excellent stability and strong tolerance to real water samples, and maintains appreciable performance even under natural sunlight illumination. The predominant active species, possible ADs decomposition pathways, and underlying reaction mechanism for the Ag/CNQDs@Fe3O4/PMS/vis system are thoroughly explored. This work presents significant advancement in enabling an integrated technology of PMS and photocatalysis to realize its great potential in environment restoration.

A green slurry electrolysis to recover valuable metals from waste printed circuit board (WPCB) in recyclable pH-neutral ethylene glycol.

The continuous growth of e-waste necessitates an efficient method to recover their metal contents to improve their recycling rate. The successful recovery of the metallic component from Waste Electrical and Electronic Equipment (WEEE) can generate great economic benefits to incentivize the industrial recycling effort. In this study, we report the use of slurry electrolysis (SE) in pH-neutral ethylene glycol (EG) electrolyte to extract and recover the metallic component from waste printed circuit broad (WPCB) powder. The system operates at room temperature and atmospheric pressure, and the electrolyte can be recycled multiple times with no signs of chemical degradation. The EG electrolyte system can oxidize the metallic component without triggering anodic gas evolution, which allowed us to incorporate a reticulated vitreous carbon (RVC) foam anode to maximize the capture and oxidation of the metal content. The system demonstrated up to 99.1% Faraday efficiency for the cathodic metal deposition and could recover Cu from the WPCB powder in a selective manner of 59.7% in the presence of 12 other metals. The SE reaction system was also scalable and displayed no compromises on the Cu recovery selectivity. With the ability to leach and recover metallic content from WPCB in a mild and chemically benign condition, the SE system displayed much promise to be adapted for industrial-scale metal recovery from WPCB.

Prospective Comparative Study Investigating Agreement between Tele-Ophthalmology and Face-to-face Consultations in Patients Presenting with Chronic Visual Loss.

INTRODUCTION: This study aims to investigate the diagnostic accuracy of store-and-forward tele-ophthalmology consultations for non-diabetic patients, aged 40 and above, presenting with vision impairment of 3 months or more, in terms of cataracts, glaucoma, and age-related macular degeneration. METHODS: This is a prospective comparative study. Enrolled subjects were independently assessed by both tele-ophthalmology and face-to-face assessment. Agreement level between the two modalities for diagnosis and severity were compared using kappa statistic. Diagnostic accuracy of tele-ophthalmology was determined using the face-to-face consultation serving as the gold standard. Costs were compared by calculating the downstream costs generated by each modality in terms of investigations and treatment. RESULTS: A total of 860 eyes of 430 patients were assessed during the study period. Tele-ophthalmology consultations had significantly high agreement with face-to-face consultations in the diagnosis and grading of all three ocular conditions; cataracts, glaucoma, and AMD. Diagnosis and grading of cataracts and AMD reached [Formula: see text] values of > 0.8, while diagnosis and grading of glaucoma reached [Formula: see text] values between 0.61 and 0.8. In terms of diagnostic accuracy, tele-ophthalmology consultations were highly sensitive and specific for AMD with greater than 99% sensitivity and specificity achieved by tele-ophthalmology. There was high specificity when diagnosing cataracts, but lower sensitivity at 87.8%. Conversely, there was high sensitivity for diagnosing glaucoma, but lower specificity at 76.5%. Downstream costs were similar between groups. CONCLUSIONS: Store-and-forward tele-ophthalmology consultations are accurate and comparable to face-to-face consultations for diagnosis and grading of cataracts, glaucoma, and AMD.