A DFT+U investigation of hydrogen adsorption on the LaFeO3 (010) surface

The ABO3 perovskite lanthanum ferrite (LaFeO3) is a technologically important electrode material for nickel-metal hydride batteries, energy storage and catalysis. However, the electrochemical hydrogen adsorption mechanism on LaFeO3 surfaces remains under debate. In the present study, we have employed spin-polarized density functional theory calculations, with the Hubbard U correction (DFT+U), to unravel the adsorption mechanism of H2 on the LaFeO3 (010) surface. We show from our calculated adsorption energies that the preferred site for H2 adsorption is the Fe-O bridge site, with an adsorption energy of −1.178 eV (including the zero point energy), which resulted in the formation of FeOH and FeH surface species. H2 adsorption at the surface oxygen resulted in the formation of a water molecule, which leaves the surface to create an oxygen vacancy. The H2 molecule is found to interact weakly with the Fe and La sites, where it is only physisorbed. The electronic structures of the surface-adsorption systems are discussed via projected density of state and Löwdin population analyses. The implications of the calculated adsorption strengths and structures are discussed in terms of the improved design of nickel–metal hydride (Ni–MH) battery prototypes based on LaFeO3

Evidence for integrating eye health into primary health care in Africa: a health systems strengthening approach

BACKGROUND: The impact of unmet eye care needs in sub-Saharan Africa is compounded by barriers to accessing eye care, limited engagement with communities, a shortage of appropriately skilled health personnel, and inadequate support from health systems. The renewed focus on primary health care has led to support for greater integration of eye health into national health systems. The aim of this paper is to demonstrate available evidence of integration of eye health into primary health care in sub-Saharan Africa from a health systems strengthening perspective. METHODS: A scoping review method was used to gather and assess information from published literature, reviews, WHO policy documents and examples of eye and health care interventions in sub-Saharan Africa. Findings were compiled using a health systems strengthening framework. RESULTS: Limited information is available about eye health from a health systems strengthening approach. Particular components of the health systems framework lacking evidence are service delivery, equipment and supplies, financing, leadership and governance. There is some information to support interventions to strengthen human resources at all levels, partnerships and community participation; but little evidence showing their successful application to improve quality of care and access to comprehensive eye health services at the primary health level, and referral to other levels for specialist eye care. CONCLUSION: Evidence of integration of eye health into primary health care is currently weak, particularly when applying a health systems framework. A realignment of eye health in the primary health care agenda will require context specific planning and a holistic approach, with careful attention to each of the health system components and to the public health system as a whole. Documentation and evaluation of existing projects are required, as are pilot projects of systematic approaches to interventions and application of best practices. Multi-national research may provide guidance about how to scale up eye health interventions that are integrated into primary health systems

Technical capacities needed to implement the WHO's primary eye care package for Africa: results of a Delphi process.

OBJECTIVE: The aim of the study was to establish the technical capacities needed to deliver the WHO African Region's primary eye care package in primary healthcare facilities. DESIGN: A two-round Delphi exercise was used to obtain expert consensus on the technical complexity of each component of the package and the technical capacities needed to deliver them using Gericke's framework of technical feasibility. The panel comprised nine eyecare experts in primary eyecare in sub-Saharan Africa. In each round panel members used a 4-point Likert scale to indicate their level of agreement. Consensus was predefined as ≥70% agreement on each statement. For round 1, statements on technical complexity were identified through a literature search of primary eyecare in sub-Saharan Africa from January 1980 to April 2018. Statements for which consensus was achieved were included in round 2, and the technical capacities were agreed. RESULTS: Technical complexity statements were classified into four broad categories: intervention characteristics, delivery characteristics, government capacity requirements and usage characteristics. 34 of the 38 (89%) statements on health promotion and 40 of the 43 (93%) statements on facility case management were considered necessary technical capacities for implementation. CONCLUSION: This study establishes the technical capacities needed to implement the WHO Africa Office primary eye care package, which may be generalisable to countries in sub-Saharan Africa

Quality of glycemic control in type 2 diabetes mellitus (T2DM) and its association with markers of coagulation and inhibitors of fibrinolysis: A case–control study in the upper west region, Ghana

Background and Aims: Type 2 diabetes mellitus (T2DM) individuals are at a higher risk of developing diabetes complications, with approximately 80% complication-related mortality. The increased morbidity and mortality among T2DM patients are partly due to dysregulated hemostasis. This study determined the quality of glycemic control in T2DM and its association with markers of coagulation and inhibitors of fibrinolysis. Methods: This case–control study recruited 90 participants involving: 30 T2DM patients with good glycemic control, 30 with poor glycemic control, and 30 nondiabetic subjects as controls at a Municipal Hospital in Ghana. Fasting blood glucose, glycated hemoglobin, activated partial thromboplastin time (APTT), prothrombin time (PT), calculated international normalized ratio (INR), and full blood count (FBC) were determined for each respondent. Plasma levels of plasminogen activator inhibitor-1 (PAI-1) and thrombin activatable fibrinolysis inhibitor (TAFI) were determined using the solid-phase sandwich enzyme-linked immunosorbent assay method. Data were analyzed using R language software. Results: Plasma PAI-1 antigen levels were significantly higher in the participants with poor glycemic control as compared to participants with good glycemic control (p \u3c 0.0001). There was no significant difference in plasma TAFI levels between the participants with poor glycemic control as compared to participants with good glycemic control (p = 0.900). T2DM patients had significantly shorter APTT, PT, and INR than controls (p \u3c 0.05). At a cut-off of ≥ 161.70 pg/μL, PAI was independently associated with increasing odds (adjusted odds ratio = 13.71, 95% confidence interval: 3.67–51.26, p \u3c 0.0001) of poor glycemic control and showed the best diagnostic accuracy for poor glycemic control (area under the curve = 0.85, p \u3c 0.0001). Conclusion: PAI-1 levels were significantly increased in T2DM with poor glycemic control and emerged as the best predictor for poor glycemic control. Good glycemic management to control the plasma levels of PAI-1 is required to prevent hypercoagulability and thrombotic disorders

Circulating tumor DNA is readily detectable among Ghanaian breast cancer patients supporting non-invasive cancer genomic studies in Africa.

Circulating tumor DNA (ctDNA) sequencing studies could provide novel insights into the molecular pathology of cancer in sub-Saharan Africa. In 15 patient plasma samples collected at the time of diagnosis as part of the Ghana Breast Health Study and unselected for tumor grade and subtype, ctDNA was detected in a majority of patients based on whole- genome sequencing at high (30×) and low (0.1×) depths. Breast cancer driver copy number alterations were observed in the majority of patients

Coagulation factors and natural anticoagulants as surrogate markers of preeclampsia and its subtypes: A case-control study in a Ghanaian population

Preeclampsia (PE) is associated with endothelial injury and hemostatic abnormalities. However, the diagnostic role of coagulation parameters and natural anticoagulants in predicting PE has not been explored in Ghana. This study assessed plasma levels of these factors as surrogate markers of PE and its subtypes. This case-control study included 90 women with PE (cases) and 90 normotensive pregnant women (controls). Blood samples were drawn for the estimation of complete blood count and coagulation tests. The prothrombin time (PT), activated partial thromboplastin time (APTT), and the calculation of the international normalized ratio (INR) were determined by an ACL elite coagulometer while the levels of protein C (PC), protein S (PS), antithrombin III (ATIII), and D-dimers were also measured using the solid-phase sandwich enzyme-linked immunosorbent assay (ELISA) method. All statistical analyses were performed using the R Language for Statistical Computing. Results showed significantly (p \u3c .05) shortened APTT (28.25 s) and higher D-dimer levels (1219.00 ng/mL) among PE women, as well as low levels of PC (1.02 g/mL), PS (6.58 g/mL), and ATIII (3.99 ng/mL). No significant difference was found in terms of PT and INR. From the receiver operating characteristic analysis, PC, PS, and ATIII could significantly predict PE and its subtypes at certain cutoffs with high accuracies (area under the curve [AUC] ≥ 0.70). Most women with PE are in a hypercoagulable state with lower natural anticoagulants. PC, PS, and ATIII are good predictive and diagnostic markers of PE and its subtypes (early-onset PE [EO-PE] and late-onset PE [LO-PE]) and should be explored in future studies

Herpes Zoster Ophthalmicus in HIV/AIDS

Herpes zoster is a common infection caused by the human herpes virus 3, the same virus that causes chickenpox. It is a member of herpes viridae, the same family as the herpes simplex virus, Epstein- Barr virus, and cytomegalovirus. Herpes zoster ophthalmicus occurs when a latent varicella zoster virus in the trigeminal ganglia involving the ophthalmic division of the nerve is reactivated. Of the three divisions of the fifth cranial nerve, the ophthalmic is involved 20 times more frequently than the other divisions