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Monodisperse and semi-faceted ultra-small templated mesoporous silica nanoparticles (US-MSNs) of 20–25 nm were synthesized using short-time hydrolysis of tetraethoxysilane (TEOS) at room temperature, followed by a dilution for nucleation quenching. According to dynamic light scattering (DLS), a two-step pH adjustment was necessary for growth termination and colloidal stabilization. The pore size was controlled by cetyltrimethylammonium bromide (CTAB), and a tiny amount of neutral surfactant F127 was added to minimize the coalescence between US-MSNs and to favor the transition towards internal ordering. Flocculation eventually occurred, allowing us to harvest a powder by centrifugation (~60% silica yield after one month). Scanning transmission electron microscopy (STEM) and 3D high-resolution transmission electron microscopy (3D HR-TEM) images revealed that the US-MSNs are partially ordered. The 2D FT transform images provide evidence for the coexistence of four-, five-, and sixfold patterns characterizing an “on-the-edge” crystallization step between amorphous raspberry and hexagonal pore array morphologies, typical of a protocrystalline state. Calcination preserved this state and yielded a powder characterized by packing, developing a hierarchical porosity centered at 3.9 ± 0.2 (internal pores) and 68 ± 7 nm (packing voids) of high potential for support for separation and catalysis.

Objectives Our study described how the WHO intra-action review (IAR) methodology was operationalised and customised in three Western Balkan countries and territories and the Republic of Moldova and analysed the common key findings to inform analyses of the lessons learnt from the pandemic response.Design We extracted data from the respective IAR reports and performed a qualitative thematic content analysis to identify common (between countries and territories) and cross-cutting (across the response pillars) themes on best practices, challenges and priority actions. The analysis involved three stages, namely: extraction of data, initial identification of emerging themes and review and definition of the themes.Setting IARs were conducted in the Republic of Moldova, Montenegro, Kosovo and the Republic of North Macedonia between December 2020 and November 2021. The IARs were conducted at different time points relative to the respective pandemic trajectories (14-day incidence rate ranging from 23 to 495 per 100 000).Results Case management was reviewed in all the IARs, while the infection prevention and control, surveillance and country-level coordination pillars were reviewed in three countries. The thematic content analysis identified four common and cross-cutting best practices, seven challenges and six priority recommendations. Recommendations included investing in sustainable human resources and technical capacities developed during the pandemic, providing continuous capacity-building and training (with regular simulation exercises), updating legislation, improving communication between healthcare providers at all levels of healthcare and enhancing digitalisation of health information systems.Conclusions The IARs provided an opportunity for continuous collective reflection and learning with multisectoral engagement. They also offered an opportunity to review public health emergency preparedness and response functions in general, thereby contributing to generic health systems strengthening and resilience beyond COVID-19. However, success in strengthening the response and preparedness requires leadership and resource allocation, prioritisation and commitment by the countries and territories themselves.

DesignUniversal voluntary HIV counselling and testing followed by prompt initiation of antiretroviral therapy (ART) for all those diagnosed HIV-infected (universal test and treat, UTT) is now a global health standard. However, its population-level impact, feasibility and cost remain unknown. Five community-based trials have been implemented in sub-Saharan Africa to measure the effects of various UTT strategies at population level: BCPP/YaTsie in Botswana, MaxART in Swaziland, HPTN 071 (PopART) in South Africa and Zambia, SEARCH in Uganda and Kenya and ANRS 12249 TasP in South Africa. This report describes and contrasts the contexts, research methodologies, intervention packages, themes explored, evolution of study designs and interventions related to each of these five UTT trials.MethodsWe conducted a comparative assessment of the five trials using data extracted from study protocols and collected during baseline studies, with additional input from study investigators. We organized differences and commonalities across the trials in five categories: trial contexts, research designs, intervention packages, trial themes and adaptations.ResultsAll performed in the context of generalized HIV epidemics, the trials highly differ in their social, demographic, economic, political and health systems settings. They share the common aim of assessing the impact of UTT on the HIV epidemic but differ in methodological aspects such as study design and eligibility criteria for trial populations. In addition to universal ART initiation, the trials deliver a wide range of biomedical, behavioural and structural interventions as part of their UTT strategies. The five studies explore common issues, including the uptake rates of the trial services and individual health outcomes. All trials have adapted since their initiation to the evolving political, economic and public health contexts, including adopting the successive national recommendations for ART initiation.ConclusionsWe found substantial commonalities but also differences between the five UTT trials in their design, conduct and multidisciplinary outputs. As empirical literature on how UTT may improve efficiency and quality of HIV care at population level is still scarce, this article provides a foundation for more collaborative research on UTT and supports evidence-based decision making for HIV care in country and internationally.

Abstract Background Wolbachia are the most widely spread endosymbiotic bacteria, present in a wide variety of insects and two families of nematodes. As of now, however, relatively little genomic data has been available. The Wolbachia symbiont can be parasitic, as described for many arthropod systems, an obligate mutualist, as in filarial nematodes or a combination of both in some organisms. They are currently classified into 16 monophyletic lineage groups (“supergroups”). Although the nature of these symbioses remains largely unknown, expanded Wolbachia genomic data will contribute to understanding their diverse symbiotic mechanisms and evolution. Results This report focuses on Wolbachia infections in three pseudoscorpion species infected by two distinct groups of Wolbachia strains, based upon multi-locus phylogenies. Geogarypus minor harbours wGmin and Chthonius ischnocheles harbours wCisc, both closely related to supergroup H, while Atemnus politus harbours wApol, a member of a novel supergroup S along with Wolbachia from the pseudoscorpion Cordylochernes scorpioides (wCsco). Wolbachia supergroup S is most closely related to Wolbachia supergroups C and F. Using target enrichment by hybridization with Wolbachia-specific biotinylated probes to capture large fragments of Wolbachia DNA, we produced two draft genomes of wApol. Annotation of wApol highlights presence of a biotin operon, which is incomplete in many sequenced Wolbachia genomes. Conclusions The present study highlights at least two symbiont acquisition events among pseudoscorpion species. Phylogenomic analysis indicates that the Wolbachia from Atemnus politus (wApol), forms a separate supergroup (“S”) with the Wolbachia from Cordylochernes scorpioides (wCsco). Interestingly, the biotin operon, present in wApol, appears to have been horizontally transferred multiple times along Wolbachia evolutionary history.

Culex pipienswWolbachia

Abstract Background Different surgical procedures have been proposed to achieve horizontal ridge reconstruction of the anterior maxilla; all these procedures, however, require bone replacement materials to be adapted to the bone defect at the time of implantation, resulting in complex and time-consuming procedures. The purpose of this study was to describe how to use a 3D printed hardcopy model of the maxilla to prepare customized milled bone blocks, to be adapted on the bone defect areas using a minimally invasive subperiosteal tunneling technique. Methods Cone beam computed tomography (CBCT) images of the atrophic maxilla of six patients were acquired and modified into 3D reconstruction models. Data were transferred to a 3D printer and solid models were fabricated using autoclavable nylon polyamide. Before the surgery, freeze-dried cortico-cancellous blocks were manually milled and adapted on the 3D printed hardcopy models of the maxillary bone, in order to obtain customized allogeneic bone blocks. Results In total, eleven onlay customized allogeneic bone grafts were prepared and implanted in 6 patients, using a minimally invasive subperiosteal tunneling technique. The scaffolds closely matched the shape of the defects: this reduced the operation time and contributed to good healing. The patients did not demonstrate adverse events such as inflammation, dehiscence or flap re-opening during the recovery period; however, one patient experienced scaffold resorption, which was likely caused by uncontrolled motion of the removable provisional prosthesis. Following a 6 month healing period, CBCT was used to assess graft integration, which was followed by insertion of implants into the augmented areas. Prosthetic restorations were placed 4 months later. Conclusions These observations suggest that customized bone allografts can be successfully used for horizontal ridge reconstruction of the anterior maxilla: patients demonstrated reduced morbidity and decreased total surgery time. Further studies on a larger sample of patients, with histologic evaluation and longer follow-up are needed to confirm the present observations.

Abstract Background Dengue virus remains a major threat in Vietnam, while chikungunya virus is expected to become one. Surveillance was conducted from 2012 to 2014 in Vietnam to assess the presence of dengue and chikungunya viruses in patients hospitalized with acute fever in five Vietnam provinces neighboring Lao PDR and Cambodia. Surveillance was extended to mosquitoes present in the vicinity of the patients’ households. Results A total 558 human serum samples were collected along with 1104 adult mosquitoes and 12,041 larvae from 2250 households. Dengue virus was found in 17 (3%) human serum samples and in 9 (0.8%) adult mosquitoes. Chikungunya virus was detected in 2 adult mosquitoes (0.18%) while no chikungunya virus was detected in humans. Differing densities of mosquito populations were found, with the highest in the Long An Province border with Cambodia. Long An Province also displayed the lowest rate of infection, despite a very high Breteau Index, high human population density and presence of the main cross border road system. The highest incidence was found in Dac Nong Province, where the Breteau and Container indices were the second lowest. Dengue virus was detected in five Aedes albopictus, three Aedes aegypti and one Culex vishnui. Chikungunya virus was detected in two Ae. aegypti. All infected mosquitoes belonged to haplotypes described in other parts of the world and a number of novel haplotypes were found among uninfected mosquitoes. Conclusions Dengue is considered to be regularly introduced to Vietnam from Cambodia, mostly through human movement. The data reported here provides a complementary picture. Due to intensive international trade, long-distance transportation of mosquito populations may play a role in the regular importation of dengue in Vietnam through Ho Chi Minh City. It is important to decipher the movement of mosquitoes in Vietnam, not only at the Lao PDR and Cambodia borders but also through international trade routes. Mosquito surveillance programs should address and follow mosquito populations instead of mosquito species.

The implementation of a quality management system within a PUI is an integral part of the tasks of a pharmacist and a pharmacy technician. In this workshop we proposed to share our ISO 9001 certified unit experience. We encouraged participants to share about their interest in a quality management system and gave them some keys for facilitating the initiation of an ISO 9001 certification.

BACKGROUND:Limited engagement in clinic-based care is affecting the HIV response. We explored the field experiences and perceptions of local health care workers regarding home-based strategies as opportunities to improve the cascade of care of people living with HIV in rural South Africa as part of a Universal Test-and-Treat approach. METHODS:In Hlabisa sub-district, home-based HIV services, including rapid HIV testing and counselling, and support for linkage to and retention in clinic-based HIV care, were implemented by health care workers within the ANRS 12249 Treatment-as-Prevention (TasP) trial. From April to July 2016, we conducted a mixed-methods study among health care workers from the TasP trial and from local government clinics, using self-administrated questionnaires (n = 90 in the TasP trial, n = 56 in government clinics), semi-structured interviews (n = 13 in the TasP trial, n = 5 in government clinics) and three focus group discussions (n = 6-10 health care workers of the TasP trial per group). Descriptive statistics were used for quantitative data and qualitative data were analysed thematically. RESULTS:More than 90% of health care workers assessed home-based testing and support for linkage to care as feasible and acceptable by the population they serve. Many health care workers underlined how home visits could facilitate reaching people who had slipped through the cracks of the clinic-based health care system and encourage them to successfully access care. Health care workers however expressed concerns about the ability of home-based services to answer the HIV care needs of all community members, including people working outside their home during the day or those who fear HIV-related stigmatization. Overall, health care workers encouraged policy-makers to more formally integrate home-based services in the local health system. They promoted reshaping the disease-specific and care-oriented services towards more comprehensive goals. CONCLUSION:Because home-based services allow identification of people early during their infection and encourage them to take actions leading to viral suppression, HCWs assessed them as valuable components within the panel of UTT interventions, aiming to reach the 90-90-90 UNAIDS targets, especially in the rural Southern African region. TRIAL REGISTRATION:The registration number of the ANRS 12249 TasP trial on ClinicalTrials.gov is NCT01509508.

BACKGROUND:We aimed to describe the field experiences and recommendations of clinic-based health care providers (HCP) regarding the implementation of universal antiretroviral therapy (ART) in rural KwaZulu-Natal, South Africa. METHODS:In Hlabisa sub-district, the local HIV programme of the Department of Health (DoH) is decentralized in 18 clinics, where ART was offered at a CD4 count ≤500 cells/μL from January 2015 to September 2016. Within the ANRS 12249 TasP trial, implemented in part of the sub-district, universal ART (no eligibility criteria) was offered in 11 mobile clinics between March 2012 and June 2016. A cross-sectional qualitative survey was conducted in April-July 2016 among clinic-based nurses and counsellors providing HIV care in the DoH and TasP trial clinics. In total, 13 individual interviews and two focus groups discussions (including 6 and 7 participants) were conducted, audio-recorded, transcribed, and thematically analyzed. RESULTS:All HCPs reported an overall good experience of delivering ART early in the course of HIV infection, with most patients willing to initiate ART before being symptomatic. Yet, HCPs underlined that not feeling sick could challenge early ART initiation and adherence, and thus highlighted the need to take time for counselling as an important component to achieve universal ART. HCPs also foresaw logistical challenges of universal ART, and were especially concerned about increasing workload and ART shortage. HCPs finally recommended the need to strengthen the existing model of care to facilitate access to ART, e.g., community-based and integrated HIV services. CONCLUSIONS:The provision of universal ART is feasible and acceptable according to HCPs in this rural South-African area. However their experiences suggest that universal ART, and more generally the 90-90-90 UNAIDS targets, will be difficult to achieve without the implementation of new models of health service delivery.

By systematically studying the evolution of the optical properties with the content of some doping elements (Eu and Tb) in cubic gadolinium oxide, we demonstrated that the luminescence quenching could be almost entirely suppressed by elaboration of the samples in the nanometer range. Indeed, even if the proportion of quenchers (here surface hydroxyl groups) does increase at this scale, each rare-earth cation possesses an electronic configuration that depends on its distance from the surface and then slightly differs from that of the surrounding atoms. This difference almost eliminates any resonant transfer of excitation between all the atoms within the particle and suppresses a significant proportion of non-radiative losses. As a consequence, the quantum yield is not affected by the phenomenon of luminescence quenching because of concentration that is usually encountered in macroscopic samples. The emission can then be increased by a factor of about 3 for Tb and 5 for Eu simply by increasing the doping content. Moreover, the lifetime is significantly increased compared to macroscopic samples and, contrary to what happens at the macroscopic scale, does not depend on the doping content. This result opens new strategies to increase the emission of many fluorophores already commercialized, provided that the bcc structure is effectively preserved in the desired application. [ABSTRACT FROM AUTHOR]

Dye quantum yield is generally measured using the method of Williams, which consists in comparing the absorbance and the emission of the dye to test with those of a reference. Unfortunately, this method is no more applicable when the sample presents some significant scattering which is, for instance, the case when the dyes are encapsulated in silica particles with a size below 100 nm. Indeed the photons scattered by the particles are further absorbed by the dyes and generate an additional light emission leading to an overestimation of the quantum yield. Nevertheless, the paper shows that the Williams’s method can be still applied if the sample is compared with a reference that has exactly the same scattering properties than those of the sample. In the case of a test sample consisting of dyes encapsulated within particles, such a reference can be easily realized by incorporating in a solution of reference dyes, an adequate proportion of particles with the same size than those of the test sample. We prove theoretically and experimentally that relevant values of quantum yield are then obtained. [ABSTRACT FROM AUTHOR]

The bulk (Fe, Ti, O) phase diagram was strongly modified at the nanometer scale because of the prohibitive interface energy between the two phases normally present at the micrometer range. With absorption spectroscopy experiments, it was evidenced that the clusters consist of a compact stack of four TiO2 entities.

The investigation of the heterogeneities in stoichiometric powders by a combination of averaging and local techniques, X-ray diffraction and Mossbauer spectrometry for an average analysis of powders, X-ray photoelectron spectroscopy for an analysis of the surface of the grains, are presented. Fe-segregation is found inside stoichimetric particles when the powders are studied.