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1.
J Synchrotron Radiat ; 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38592969

RESUMO

Experimental characterization of the structural, electronic and dynamic properties of dilute systems in aqueous solvents, such as nanoparticles, molecules and proteins, are nowadays an open challenge. X-ray absorption spectroscopy (XAS) is probably one of the most established approaches to this aim as it is element-specific. However, typical dilute systems of interest are often composed of light elements that require extreme-ultraviolet to soft X-ray photons. In this spectral regime, water and other solvents are rather opaque, thus demanding radical reduction of the solvent volume and removal of the liquid to minimize background absorption. Here, we present an experimental endstation designed to operate a liquid flat jet of sub-micrometre thickness in a vacuum environment compatible with extreme ultraviolet/soft XAS measurements in transmission geometry. The apparatus developed can be easily connected to synchrotron and free-electron-laser user-facility beamlines dedicated to XAS experiments. The conditions for stable generation and control of the liquid flat jet are analyzed and discussed. Preliminary soft XAS measurements on some test solutions are shown.

3.
Public Health Pract (Oxf) ; 6: 100448, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38028255

RESUMO

Objectives: The health emergency following the COVID-19 pandemic has seen hospital structures collapse and put in crisis nursing homes and other long-term care facilities worldwide. Our study aims to analyze and comparing the data relating to the infection rate and mortality for COVID-19 in the elderly over 75 living in the long-term care facilities and in the home-dwelling population. Study design: The study adopts a retrospective cohort design and was conducted in Italy, in the Lazio region, in the area of the Local Health Authority (LHA) named "Azienda Sanitaria Locale Roma 6". Methods: Data were extracted from the COVID-19 surveillance system of the Lazio region. The primary outcome is the SARS-CoV-2 incidence rate in the period between 1st September 2020 and 31st May 2021. The secondary outcome is the mortality rate. Results: Living in a residential versus a home-dwelling setting was associated with a higher infection rate (OR 5.03, CI 4.67-5.43; p < 0.001). The mortality rate was higher for individuals living in a residential setting (19.3 %, CI 17.1%-21.7 %) than those living at home (13.0 %, CI 11.7%-14.5 %). Conclusions: These findings confirm the high mortality in Long-Term Care Facilities and provide new information on the infection rate. The containment measures adopted in the Long-Term Care Facilities during the COVID-19 pandemic, show limited correlation with reduced risk of contagion, but could have created unintended harm for the residents by increasing the social isolation and all other causes of mortality.

4.
Trop Med Int Health ; 28(9): 731-735, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37533039

RESUMO

Measles vaccination is currently recommended at 9 months, since maternal antibodies are supposed to protect infants until that age. In this study of 6-month-old Malawian infants 98.3% (58/59) had non-protective IgG levels against measles, irrespective of HIV exposure. Anticipating the first dose at 6 months could be considered.


Assuntos
Sarampo , Humanos , Lactente , Sarampo/prevenção & controle , Vacinação , Anticorpos Antivirais , Esquemas de Imunização , Vacina contra Sarampo
5.
Acta Trop ; 246: 106987, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37454709

RESUMO

In sub-Saharan Africa the great majority of infants acquire Cytomegalovirus (CMV) infection within the first year of life. Maternal long-term antiretroviral therapy (ART) has been suggested to reduce the rate of CMV acquisition in HIV-exposed infants. In the present study serum samples collected at 6 months of age from HIV-exposed and HIV-unexposed infants were analyzed for the presence of CMV DNA (with CMV positivity defined by levels of CMV DNA > 1000 UI/ml). Twenty out of 58 (34.5%) infants had CMV DNA > 1000 UI/ml. There was no difference in the prevalence of CMV viremia between HIV-exposed and -unexposed infants [33.3% (15/45) vs 38.5% (5/13), respectively, P = 0.488]. In the HIV-exposed group, mothers of CMV-negative infants had received a longer antiretroviral treatment before delivery in comparison to mothers of CMV-positive infants (28 vs 3 months, P = 0.187). No differences in weights and lengths at birth, and at 1, 6 and 12 months were observed between CMV-positive and CMV-negative infants. In this study, the prevalence of CMV viremia at six months of age was high in infants born to HIV-positive mothers receiving long-term ART, similar to that of HIV-unexposed infants. Considering the possible relevant impact of CMV on infant health, strategies for containment of the infection should be explored.


Assuntos
Infecções por Citomegalovirus , Infecções por HIV , Complicações Infecciosas na Gravidez , Recém-Nascido , Feminino , Humanos , Lactente , Gravidez , Citomegalovirus , Viremia/tratamento farmacológico , Malaui/epidemiologia , Transmissão Vertical de Doenças Infecciosas , Infecções por Citomegalovirus/epidemiologia , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Complicações Infecciosas na Gravidez/tratamento farmacológico , Complicações Infecciosas na Gravidez/epidemiologia
6.
Nutrients ; 15(14)2023 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-37513701

RESUMO

Breastfed Malawian infants from Human Immunodeficiency Virus (HIV)-uninfected and HIV-infected women who received antiretroviral therapy were followed until 12 months of age, allowing us to evaluate plasma levels of ferritin, vitamin A (as retinol-binding protein, RBP), and vitamin D (25(OH)D) at six months, as well as nutritional status and growth between six and 12 months. Ferritin and RBP levels were adjusted for inflammation. The study included 88 infants, 63 of whom were part of a recent cohort (2019-2021) that included 49 HIV-exposed but uninfected (HEU) and 14 HIV-unexposed and uninfected (HUU) infants, as well as 25 infants (all HEU) from an earlier cohort (2008-2011). No differences were observed between HEU and HUU infants regarding micronutrient levels, anthropometric indexes, growth, and rates of stunting, being underweight, or wasting. HEU infants from the earlier cohort, when compared to more recent HEU infants, had significantly worse anthropometric measures at six months and inferior growth between six and twelve months. Overall, ferritin deficiency involved 68.6% of infants, while vitamin A and vitamin D deficiency involved 8% and 1.2% of infants, respectively. Micronutrient deficiencies were not associated with HIV exposure, cohort, stunting, being underweight, or wasting. At six months, stunting, being underweight, and wasting involved 25.0%, 2.7% and 2.8% of infants, respectively, with no differences related to HIV exposure. Ferritin deficiency at six months was associated with inferior subsequent growth. In this small observational study conducted in Malawian infants, no major nutritional gap was observed between HIV-exposed and HIV-unexposed infants, though the study highlighted specific nutritional deficiencies that deserve attention. High rates of stunting and ferritin deficiency were observed in the first year of life in Malawian infants, irrespective of maternal HIV status; a significant association between ferritin deficiency and worse subsequent growth was found. Vitamin A and vitamin D deficiencies were much less frequent. Based on the data observed, nutritional interventions should give priority to the correction of ferritin deficiency and chronic undernutrition.


Assuntos
Infecções por HIV , Desnutrição , Oligoelementos , Deficiência de Vitamina D , Humanos , Lactente , Feminino , Estado Nutricional , Vitamina A , HIV , Ferritinas , Micronutrientes , Magreza/complicações , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , Transtornos do Crescimento/etiologia , Transtornos do Crescimento/complicações , Desnutrição/complicações , Caquexia/complicações , Deficiência de Vitamina D/complicações
7.
Pathogens ; 12(7)2023 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-37513785

RESUMO

BACKGROUND: The evaluation of seroprotection rates against vaccine-preventable infectious diseases allows for the identification of risk populations. HIV-exposed infants, even if not infected with HIV, have higher morbidity and mortality in comparison to unexposed counterparts. The aim of this study was to compare the specific IgG levels against Haemophilus influenzae type-B (HiB), Hepatitis-B (HBV), and Streptococcus pneumoniae (Spn) in two groups of infants (HIV-exposed and HIV-unexposed) living in Malawi. METHODS: Blood samples from 62 infants, 49 HIV-exposed, uninfected (HEU), and born to women living with HIV and 13 HIV-unexposed and uninfected (HUU), were collected at 6 months, and specific IgG levels were determined using ELISA tests. RESULTS: The antibody levels against HiB, HBV, and Spn were similar in the two groups. At six months, all HUU infants and 81.6% of HEU infants showed seroprotective levels against HiB, while a percentage of protection varying from 80.6 to 84.6% was observed for HBV and Spn regardless of HIV exposure. Only 59.2% of HEU and 69.2% of HUU infants showed antibody protection against all three pathogens. CONCLUSIONS: These results indicate similar rates of seroprotection among HEU and HUU infants but also suggest that a consistent fraction of infants received incomplete vaccinations. Strategies to enforce participation in immunization programs in Malawi should be a health priority.

9.
Eur J Cancer Prev ; 32(5): 431-437, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37144587

RESUMO

OBJECTIVE: Cervical cancer (CC) is a global health issue, in Mozambique, 5300 new cases and 3800 deaths are reported each year. The WHO recommends the introduction of HPV molecular testing for CC screening, but Mozambique uses an approach based on visual inspection with acetic acid (VIA). This study aims to evaluate the feasibility of high-risk HPV (hrHPV) testing compared to actual approaches in Mozambique. METHODS: An observational study was carried out in the DREAM center in Zimpeto, Mozambique. Women aged 30-55 were included. HPV testing was performed with the Cobas HPV test. They were then screened with the current national recommendations based on VIA. Cryotherapy was performed on-site or referred for colposcopy if necessary. RESULTS: In the period, 1207 women were enrolled, 47.8% HIV+; 124 (10.3%) VIA+, and HPV DNA test was positive in 325 (26.9%) women. HPV positivity rates were higher in HIV-infected women. In the sample, 52.8% of the 124 VIA+ women were HPV uninfected and underwent unnecessary cryotherapy or colposcopy. Meanwhile, 24.7% of the 1083 VIA- women were actually HPV infected. In comparison, a screen, triage and treat approach based on hrHPV testing would only test and treat the 325 HPV-infected women. CONCLUSION: The study found high rates of hrHPV infection, particularly in HIV-positive women, with many concurrent or multiple infections. The current screening method misses important hrHPV infections and results in many unnecessary treatments. These results support the use of HPV molecular testing as the initial screening test for CC.


Assuntos
Infecções por HIV , Infecções por Papillomavirus , Displasia do Colo do Útero , Neoplasias do Colo do Útero , Feminino , Humanos , Masculino , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/epidemiologia , Displasia do Colo do Útero/diagnóstico , Infecções por Papillomavirus/diagnóstico , Infecções por Papillomavirus/epidemiologia , Moçambique/epidemiologia , Papillomaviridae/genética , Detecção Precoce de Câncer/métodos , Programas de Rastreamento/métodos , Ácido Acético , Infecções por HIV/complicações , Infecções por HIV/diagnóstico , Infecções por HIV/epidemiologia
10.
Nanomaterials (Basel) ; 13(10)2023 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-37242107

RESUMO

Tantalum boride is an ultra-refractory and ultra-hard ceramic known so far for its favorable high-temperature thermo-mechanical properties and also characterized by a low spectral emittance, making it interesting for novel high-temperature solar absorbers for Concentrating Solar Power. In this work, we investigated two types of TaB2 sintered products with different porosities, and on each of them, we realized four femtosecond laser treatments differing in the accumulated laser fluence. The treated surfaces were then characterized by SEM-EDS, roughness analysis, and optical spectrometry. We show that, depending on laser processing parameters, the multi-scale surface textures produced by femtosecond laser machining can greatly increase the solar absorptance, while the spectral emittance increase is significantly lower. These combined effects result in increased photothermal efficiency of the absorber, with interesting perspectives for the application of these ceramics in Concentrating Solar Power and Concentrating Solar Thermal. To the best of our knowledge, this is the first demonstration of successful photothermal efficiency enhancement of ultra-hard ceramics using laser machining.

12.
PLoS One ; 18(3): e0282019, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36961857

RESUMO

INTRODUCTION: Healthcare-associated infections (HAIs) and antimicrobial resistance (AMR) are major public health threats in upper- and lower-middle-income countries. Electronic health records (EHRs) are an invaluable source of data for achieving different goals, including the early detection of HAIs and AMR clusters within healthcare settings; evaluation of attributable incidence, mortality, and disability-adjusted life years (DALYs); and implementation of governance policies. In Italy, the burden of HAIs is estimated to be 702.53 DALYs per 100,000 population, which has the same magnitude as the burden of ischemic heart disease. However, data in EHRs are usually not homogeneous, not properly linked and engineered, or not easily compared with other data. Moreover, without a proper epidemiological approach, the relevant information may not be detected. In this retrospective observational study, we established and engineered a new management system on the basis of the integration of microbiology laboratory data from the university hospital "Policlinico Tor Vergata" (PTV) in Italy with hospital discharge forms (HDFs) and clinical record data. All data are currently available in separate EHRs. We propose an original approach for monitoring alert microorganisms and for consequently estimating HAIs for the entire period of 2018. METHODS: Data extraction was performed by analyzing HDFs in the databases of the Hospital Information System. Data were compiled using the AREAS-ADT information system and ICD-9-CM codes. Quantitative and qualitative variables and diagnostic-related groups were produced by processing the resulting integrated databases. The results of research requests for HAI microorganisms and AMR profiles sent by the departments of PTV from 01/01/2018 to 31/12/2018 and the date of collection were extracted from the database of the Complex Operational Unit of Microbiology and then integrated. RESULTS: We were able to provide a complete and richly detailed profile of the estimated HAIs and to correlate them with the information contained in the HDFs and those available from the microbiology laboratory. We also identified the infection profile of the investigated hospital and estimated the distribution of coinfections by two or more microorganisms of concern. Our data were consistent with those in the literature, particularly the increase in mortality, length of stay, and risk of death associated with infections with Staphylococcus spp, Pseudomonas aeruginosa, Klebsiella pneumoniae, Clostridioides difficile, Candida spp., and Acinetobacter baumannii. Even though less than 10% of the detected HAIs showed at least one infection caused by an antimicrobial resistant bacterium, the contribution of AMR to the overall risk of increased mortality was extremely high. CONCLUSIONS: The increasing availability of health data stored in EHRs represents a unique opportunity for the accurate identification of any factor that contributes to the diffusion of HAIs and AMR and for the prompt implementation of effective corrective measures. That said, artificial intelligence might be the future of health data analysis because it may allow for the early identification of patients who are more exposed to the risk of HAIs and for a more efficient monitoring of HAI sources and outbreaks. However, challenges concerning codification, integration, and standardization of health data recording and analysis still need to be addressed.


Assuntos
Anti-Infecciosos , Infecção Hospitalar , Humanos , Inteligência Artificial , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/microbiologia , Hospitais Universitários , Fatores de Risco
13.
Int J Nurs Sci ; 10(1): 38-45, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36860714

RESUMO

Objectives: Bio-psycho-social frailty is related to increased risk of death and utilization of health services. This paper reports the predictive validity of a 10-min multidimensional questionnaire on the risk of death, hospitalization and institutionalization. Methods: A retrospective cohort study was performed based on data from the "Long Live the Elderly!" program, involving 8,561 community-dwelling Italian people >75, followed for an average of 516.6 days (Median = 448, P 25-P 75: 309-692). Mortality, hospitalization, and institutionalization rates according to frailty levels assessed by the Short Functional Geriatric Evaluation (SFGE) have been calculated. Results: Compared with the robust, the pre-frail, frail, and very frail faced a statistically significant increase in the risk of mortality (RR = 1.40, 2.78 and 5.41), hospitalization (OR = 1.31, 1.67, and 2.08) and institutionalization (OR = 3.63, 9.52, and 10.62). Similar results were obtained in the sub-sample of those with only socio-economic issues. Frailty predicted mortality with an area under the ROC curve of 0.70 (95% CI 0.68-0.72) with sensitivity and specificity of 83.2% and 40.4%. Analyses of single determinants of these negative outcomes showed a multivariable pattern of determinants for all the events. Conclusions: The SFGE predicts death, hospitalization and institutionalization by stratifying older people according to the levels of frailty. The short administration time, the socio-economic variables and the characteristics of personnel administering the questionnaire make it suitable for being used in public health as a screening tool for a large population, to put frailty at the core of the care for community-dwelling older adults. The difficulty in capturing the complexity of the frailty is witnessed by the moderate sensitivity and specificity of the questionnaire.

14.
Artigo em Inglês | MEDLINE | ID: mdl-36901153

RESUMO

The Short Functional Geriatric Evaluation (SFGE) is a multidimensional and short questionnaire to assess biopsychosocial frailty in older adults. This paper aims to clarify the latent factors of SFGE. Data were collected from January 2016 to December 2020 from 8800 community-dwelling older adults participating in the "Long Live the Elderly!" program. Social operators administered the questionnaire through phone calls. Exploratory factor analysis (EFA) was carried out to identify the quality of the structure of the SFGE. Principal component analysis was also performed. According to the SFGE score, 37.7% of our sample comprised robust, 24.0% prefrail, 29.3% frail, and 9.0% very frail individuals. Using the EFA, we identified three main factors: psychophysical frailty, the need for social and economic support, and the lack of social relationships. The Kaiser-Meyer-Olkin measure of sampling adequacy was 0.792, and Bartlett's test of sphericity had a statistically significant result (p-value < 0.001). The three constructs that emerged explain the multidimensionality of biopsychosocial frailty. The SFGE score, 40% of which is social questions, underlines the crucial relevance of the social domain in determining the risk of adverse health outcomes in community-dwelling older adults.


Assuntos
Fragilidade , Humanos , Idoso , Idoso Fragilizado , Vida Independente , Avaliação Geriátrica/métodos , Inquéritos e Questionários
15.
Micromachines (Basel) ; 14(2)2023 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-36838089

RESUMO

Polycrystalline boron-doped diamond (BDD) films were surface nanotextured by femtosecond pulsed laser irradiation (100 fs duration, 800 nm wavelength, 1.44 J cm-2 single pulse fluence) to analyse the evolution of induced alterations on the surface morphology and structural properties. The aim was to identify the occurrence of laser-induced periodic surface structures (LIPSS) as a function of the number of pulses released on the unit area. Micro-Raman spectroscopy pointed out an increase in the graphite surface content of the films following the laser irradiation due to the formation of ordered carbon sites with respect to the pristine sample. SEM and AFM surface morphology studies allowed the determination of two different types of surface patterning: narrow but highly irregular ripples without a definite spatial periodicity or long-range order for irradiations with relatively low accumulated fluences (<14.4 J cm-2) and coarse but highly regular LIPSS with a spatial periodicity of approximately 630 nm ± 30 nm for higher fluences up to 230.4 J cm-2.

16.
Nanomaterials (Basel) ; 13(2)2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36677993

RESUMO

A recent innovation in diamond technology has been the development of the "black diamond" (BD), a material with very high optical absorption generated by processing the diamond surface with a femtosecond laser. In this work, we investigate the optical behavior of the BD samples to prove a near to zero dielectric permittivity in the high electric field condition, where the Frenkel-Poole (FP) effect takes place. Zero-epsilon materials (ENZ), which represent a singularity in optical materials, are expected to lead to remarkable developments in the fields of integrated photonic devices and optical interconnections. Such a result opens the route to the development of BD-based, novel, functional photonic devices.

17.
Int J Adolesc Med Health ; 35(2): 227-231, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36708359

RESUMO

INTRODUCTION: Around 1,7 million adolescents aged 10-19 years worldwide are infected with HIV, 84% of them living in Sub-Saharan Africa. Mozambique is one of the countries with the highest prevalence of HIV in the world. According to UNAIDS, HIV services for adolescents should be tailored and specifically designed for them. METHODS: We aimed to evaluate a package of activities to enhance the retention of HIV-infected adolescent in Mozambique. We retrospectively reviewed routine data from 7 health centers involved in 26 months, from March 2020 to May 2022. A package of tailored interventions was implemented in all the sites. We reviewed activity data from the included centers. RESULTS: The median number of patients per center was 343 (IQR: 289-466) at the beginning of the period and 395 (IQR: 322-453) at the end. The median overall retention in care and rate of lost to follow-up at the beginning and the end of the period were respectively: 94.2% (IQR 91.9-97.3%) to 99.0% (IQR 96.8-99.5%), 1.5% (IQR 1-3.2%) to 0% (IQR 0.0-0.3%). The total number of deaths increased reaching a plateau after September 2021. All the indicators improved after the beginning of the intervention, also during COVID-19 pandemic. CONCLUSIONS: Our data support the idea that enhancing retention in care for HIV positive adolescents need tailored interventions, based on deep rooting in the specific social context. Tailored intervention can resist external shock such as COVID-19.


Assuntos
COVID-19 , Infecções por HIV , Retenção nos Cuidados , Humanos , Adolescente , Infecções por HIV/epidemiologia , Infecções por HIV/terapia , Estudos Retrospectivos , Moçambique/epidemiologia , Pandemias , COVID-19/epidemiologia
18.
Int J STD AIDS ; 34(1): 54-61, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36285600

RESUMO

BACKGROUND: Post-partum loss to follow-up and lack of early HIV infant diagnosis (EID) can significantly affect the efficiency of programs for the prevention of mother-to-child transmission. METHODS: In a prospective observational study 167 women were enrolled at week 36 of gestation and followed with their infants up to one year after delivery. Retention was defined as the proportion of women who attended the 12 months visit and EID as an HIV PCR test performed within 2 months. Determinants for retention and EID were assessed in univariate analyses and in multivariable logistic regression models. RESULTS: Women lost to follow-up (24/167 or 14.4%) had a shorter duration of antiretroviral therapy (ART) at enrolment in comparison to women retained in care (p = 0.025). Lack of EID (occurring in 18.9% of the cases) was directly correlated, although not significantly, with a history of child death (p = 0.071), a higher educational level (p = 0.083), and female infant gender (p = 0.064). CONCLUSIONS: Longer duration of ART at enrolment significantly predicted a better post-partum retention, suggesting that specific counselling interventions should be targeted to recent ART initiators. A low proportion of infants did not receive an EID, but predictive factors were difficult to identify.


Assuntos
Infecções por HIV , Complicações Infecciosas na Gravidez , Lactente , Feminino , Humanos , Gravidez , Estudos Prospectivos , Malaui/epidemiologia , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Infecções por HIV/diagnóstico , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Diagnóstico Precoce , Complicações Infecciosas na Gravidez/diagnóstico , Complicações Infecciosas na Gravidez/tratamento farmacológico , Complicações Infecciosas na Gravidez/epidemiologia
19.
Am J Trop Med Hyg ; 108(2): 394-402, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36535249

RESUMO

Few studies have compared clinical outcomes in HIV-exposed uninfected (HEU) and HIV-unexposed uninfected (HUU) infants in the current scenario of universal and lifelong maternal antiretroviral therapy (ART). HIV-uninfected and HIV-infected Malawian women receiving ART and their breastfed infants were followed for 12 months postpartum, analyzing the rates of infectious and noninfectious events and assessing infant growth at 6 weeks, 6 months, and 12 months. The cohorts included 227 mothers (70 HIV-negative, 157 HIV-positive) and 235 infants (72 HUU, 163 HEU). No maternal or infant deaths occurred during follow-up. HIV-negative women were less likely to complete follow-up (48.6% versus 91.1%). Mothers with and without HIV had similar rates of both infectious and noninfectious events per person-month. Infants who were HEU, compared with HUU, had higher rates of events of any type, lower respiratory tract infections (LRTI), and noninfectious events. HEU had lower body mass index (BMI) at 6 weeks but did not differ from HUU in all anthropometric measures at 6 and 12 months; in growth between 6 weeks and 12 months; and in occurrence of stunting, underweight, and wasting at 6 weeks, 6 months, and 12 months. During the first year of life, infants who were HEU, compared with HUU, showed a transiently lower BMI and an increased risk of LRTI.


Assuntos
Doenças Transmissíveis , Infecções por HIV , Infecções Respiratórias , Lactente , Humanos , Feminino , Estudos Prospectivos , Malaui/epidemiologia , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Aleitamento Materno
20.
Materials (Basel) ; 15(23)2022 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-36499821

RESUMO

Surfaces of commercial molybdenum (Mo) plates have been textured by fs-laser treatments with the aim to form low-cost and efficient solar absorbers and substrates for thermionic cathodes in Concentrated Solar Power conversion devices. Morphological (SEM and AFM), optical (spectrophotometry), and structural (Raman spectroscopy) properties of the samples treated at different laser fluences (from 1.8 to 14 J/cm2) have been characterized after the laser treatments and also following long thermal annealing for simulating the operating conditions of thermionic converters. A significant improvement of the solar absorptance and selectivity, with a maximum value of about four times higher than the pristine sample at a temperature of 800 K, has been detected for sample surfaces treated at intermediate fluences. The effects observed have been related to the light trapping capability of the laser-induced nanotexturing, whereas a low selectivity, together with a high absorptance, could be revealed when the highest laser fluence was employed due to a significant presence of oxide species. The ageing process confirms the performance improvement shown when treated samples are used as solar absorbers, even though, due to chemical modification occurring at the surface, a decrease of the solar absorptance takes place. Interestingly, the sample showing the highest quantity of oxides preserves more efficiently the laser texturing. The observation of this behaviour allows to extend the applicability of the laser treatments since, by further nanostructuring of the Mo oxides, it could be beneficial also for sensing applications.

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