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According to intermediate band (IB) theory, it is possible to increase the efficiency of a solar cell by boosting its ability to absorb low-energy photons. In this study, we used a hyperdoped semiconductor approach for this theory to create a proof of concept of different silicon-based IB solar cells. Preliminary results show an increase in the external quantum efficiency (EQE) in the silicon sub-bandgap region. This result points to sub-bandgap absorption in silicon having not only a direct application in solar cells but also in other areas such as infrared photodetectors. To establish the transport mechanisms in the hyperdoped semiconductors within a solar cell, we measured the J â€" V characteristic at different temperatures. We carried out the measurements in both dark and illuminated conditions. To explain the behavior of the measurements, we proposed a new model with three elements for the IB solar cell. This model is similar to the classic two-diodes solar cell model but it is necessary to include a new limiting current element in series with one of the diodes. The proposed model is also compatible with an impurity band formation within silicon bandgap. At high temperatures, the distance between the IB and the n-type amorphous silicon conduction band is close enough and both bands are contacted. As the temperature decreases, the distance between the bands increases and therefore this process becomes more limiting. [ABSTRACT FROM AUTHOR]

Abstract Many of the energy systems functioning across the developing world are poorly designed and largely inadequate to meet a country's commercial and domestic energy needs. This is especially so in Latin America, where poverty trends have been exacerbated by limited access to energy, which could be used towards supporting industrial and small-scale commercial activities. This has characterised the widespread trend of energy poverty. This phenomenon poses a major barrier towards achieving the UN Sustainable Development Goals (SDGs) and addressing climate change, since lack of access to reliable energy generation systems hinders the development of economic activities and limits the comfort of living conditions. This paper reports on a study aimed at catering to a better understanding of the challenges related to energy poverty in Latin America and identifying some of the tools that may be deployed to address them. The methodological procedures used were bibliometric analysis and survey. The main findings of this research evidence that reducing energy poverty in Latin American countries is crucial to alleviating household costs since a considerable part of family income is used to pay the energy needs. Less use of coal, greater access to electricity—including those from renewable generation—as well as the use of technologies and programs subsidized by governments would significantly contribute to increasing the Latin American citizens' quality of life and achieving the SDGs.

In the scope of supersaturated semiconductors for infrared detectors, we implanted Si samples with Ti at high doses and processed them by rapid thermal annealing (RTA) to recover the crystal quality. Also, for comparative purposes, some samples were processed by pulsed-laser melting. We measured the electronic transport properties at variable temperatures and analyzed the results. The results indicate that, for RTA samples, surface layers with a high Ti concentration have negligible conductivity due to defects. In contrast, the implantation tail region has measurable conductivity due to very high electron mobility. This region shows the activation of a very shallow donor and a deep donor level. While deep levels have been previously reported for Ti in Si, such a shallow level has never been measured, and we suggest that it originates from Ti-Si complexes. Finally, a decoupling effect between the implanted layer and the substrate seems to be present, and a bilayer model is applied to fit the measured properties. The fitted parameters follow the Meyer–Neldel rule. The role of the implantation tails in Si supersaturated with Ti is revealed in this work. [ABSTRACT FROM AUTHOR]

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Communicating living systems detect and process a multiplicity of events with degeneracy, to continuously cope with environmental aleatoric incertitude. The concept of holon, communicating at various scales of living organizations, is hereafter formalized through dynamical systems driven by the multiplicity of statistical models. Then, the stimulus-response of elementary biological holons can be modeled by memoryless Boolean automata with different signal processing methods, in presence of noise and stochastic interference. Detection of a specified signal, to update the automaton state, can be performed via multiple families of update functions, with differentiated balances between sensitivity and specificity in presence of interference: (i) Neyman-Pearson update functions provide the best possible sensitivity to detect the signal of interest in absence of interference, but cannot guarantee a desired specificity; (ii) by detecting large amplitudes of any signal in noise, update functions based on Random Distortion Testing yield a suboptimal sensitivity to detect the signal in noise, but guarantee a wanted specificity even in presence of interference. Thus, statistical inference theories offer functional and structural redundancy and open prospects to model fractal-like holarchies, via networks of communicating degenerated automata, to feature properties of the immune system.

Purpose: To assess the healing rate of scaphoid pseudoarthrosis treated with wrist arthroscopy, olecranon bone graft, and anterograde screw fixation, as well as evaluate complications and clinical and radiologic outcomes., Methods: All patients with scaphoid nonunion were selected between January 2017 and December 2022. Inclusion criteria were patients between 18 and 60 years of age, a diagnosis of scaphoid pseudoarthrosis, complete clinical patient-reported outcomes, radiographic measurements, and at least a 1-year follow-up. Scaphoid pseudoarthrosis was treated arthroscopically with olecranon bone graft and anterograde screw fixation. Clinical assessment was performed through visual analog scale (VAS) for pain, QuickDASH (Disabilities of the Arm, Shoulder, and Hand) questionnaire, wrist range of motion using a standard goniometer, and grip strength in kilograms with a Jamar hydraulic hand dynamometer. Clinical relevance was measured with the minimal clinically important difference (MCID) for VAS and QuickDASH. Scapholunate angle was measured. Union was assessed on a computed tomography scan., Results: Seventeen patients were included with a mean follow-up of 17.2 months. The mean age was 30.1 years, and the average time from injury to arthroscopic surgery was 11.1 months. At latest follow-up, there was an improvement in VAS pain score and QuickDASH score. Range of motion and grip strength increased at last follow-up. MCID threshold for the VAS and QuickDASH score was reached by 100% and 94.1%, respectively. Union was achieved in 16 patients (94.1%) after a median of 16 weeks (interquartile range, 16-20)., Conclusions: Arthroscopic treatment of scaphoid pseudoarthrosis with olecranon bone graft and antegrade percutaneous headless compression screw allows a high grade of union and improves pain and function at short-term follow-up., Level of Evidence: Level IV, therapeutic case series., Competing Interests: Disclosures All authors (D.B.S.d.P., D.B.P., J.C.L., R.C.G., C.V.R., J.S-R.) declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.)

We aimed to assess motoric cognitive risk syndrome (MCRS) as a mortality predictor in older male adults with cancer at Centro Médico Naval (CEMENA) in Peru from 2012 to 2015. We conducted a secondary analysis of a prospective cohort within CEMENA's Geriatrics Service. We considered all-cause mortality as the primary outcome. MCRS was defined as slow gait speed, cognitive impairment, preserved activities of daily living, and absence of dementia. We utilized Poisson family generalized linear models with a logarithmic link function and robust variance to calculate both crude and adjusted relative risks (RR) with 95 % confidence intervals (95 % CI). We included 832 older male adults, with an MCRS frequency of 18.27 % (n = 152) and a mortality incidence of 22.84 % (n = 190). MCRS was a predictor of mortality in older adults at the end of follow-up (aRR=2.55; 95 % CI: 2.13-2.66). Survival was lower in older adults with MCRS (log-rank test p < 0.001). MCRS was a mortality predictor in older male adults with cancer., Competing Interests: Declaration of competing interest The authors have no conflicts of interest., (Copyright © 2024 Elsevier Inc. All rights reserved.)

In 2015, Catalonia introduced sickle cell disease (SCD) screening in its newborn screening (NBS) program along with standard-of-care treatments like penicillin, hydroxyurea, and anti-pneumococcal vaccination. Few studies have assessed the clinical impact of introducing NBS programs on SCD patients. We analyzed the incidence of SCD and related hemoglobinopathies in Catalonia and the change in clinical events occurring after introducing NBS. Screening 506,996 newborns from 2015 to 2022, we conducted a retrospective multicenter study including 100 screened (SG) and 95 unscreened (UG) SCD patients and analyzed SCD-related clinical events over the first six years of life. We diagnosed 160 cases of SCD, with an incidence of 1 in 3169 newborns. The SG had a significantly lower median age at diagnosis (0.1 y vs. 1.68 y, p < 0.0001), and initiated penicillin prophylaxis (0.12 y vs. 1.86 y, p < 0.0001) and hydroxyurea treatment earlier (1.42 y vs. 4.5 y, p < 0.0001). The SG experienced fewer median SCD-related clinical events (vaso-occlusive crisis, acute chest syndrome, infections of probable bacterial origin, acute anemia requiring transfusion, acute splenic sequestration, and pathological transcranial Doppler echography) per year of follow-up (0.19 vs. 0.77, p < 0.0001), a reduced number of annual emergency department visits (0.37 vs. 0.76, p < 0.0001), and fewer hospitalizations (0.33 vs. 0.72, p < 0.0001). SCD screening in Catalonia's NBS program has effectively reduced morbidity and improved affected children's quality of life.

Background: The prevalence of frailty and activities of daily living (ADL) disability may be higher in high-altitude Andean regions, due to chronic hypoxia, malnutrition, and physical challenges. and their association is relevant. This study aimed to evaluate the association between frailty and ADL disability among older adults residing in the Totos district in Peru during the year 2022., Methods: A cross-sectional study was conducted in Totos district (mean altitude: 3286 m above sea level), located in Ayacucho, Peru, during 2022. A complete census was employed including residents aged 60 and above. The exposure variable was frailty, defined by fulfilling 3 or more criteria of the Fried phenotype. The outcome variable was ADL disability, defined as a score below 95 on the Barthel index. Generalized linear models with a Poisson family, logarithmic link function, and robust variances were employed to estimate crude prevalence ratios and adjusted prevalence ratios (aPRs), along with their corresponding 95% confidence intervals (CIs)., Results: We evaluated 272 older adults with a mean age of 74 years, of whom 59.9% were female, 62.1% were cohabiting or married and 83.1% had not completed primary education. We found that 19.5% were frail, while 51.1% had ADL disability. In the adjusted regression model, we found frailty increased the prevalence of ADL disability (aPR = 1.77; 95%CI: 1.44-2.16; p < 0.001)., Conclusion: Frailty was associated with an increased prevalence of ADL disability. These findings could contribute to establishing government intervention plans to manage disability and frailty within the high-risk group comprising older adults living at high altitudes., (© 2024. The Author(s).)

Background : Microarray patches (MAPs) are innovative, needle-free vaccine delivery systems, suitable for administration by minimally trained health care workers or trained community health workers. Their introduction may transform immunization programmes, particularly for vaccines where high coverage is required for population immunity, such as measles, and where vaccine delivery is challenging, such as in low- and middle-income countries. Recognizing the need to understand how best to tailor these products to reflect country priorities, workshops on measles and rubella MAPs (MR-MAPs) were conducted in multiple regions to collect insights on needs and preferences from relevant stakeholders at country level. Methods : The CAPACITI Innovation Framework was used to structure stakeholder discussions in nine countries in the period from August 2022 to July 2023. The discussions, building on the findings from a situation analysis on the barriers related to measles and rubella vaccine delivery, followed the four-step process outlined in the framework. Results : Key barriers hindering delivery of measles and rubella vaccines across the countries were in the categories of human resource management, service delivery, and demand generation. MR-MAP attributes that stakeholders believed would reduce or eliminate these barriers included ease of preparation and administration, improved thermostability, fewer (ancillary) components, and single-dose presentation. Some attributes such as the site of administration, wear time, and storage volume could exacerbate certain barriers. Based on an understanding of key barriers, product attributes, and underserved populations, stakeholders identified several potential use cases for MR-MAPs: (i) delivery at a fixed health post, (ii) delivery through outreach sessions conducted by health workers, and (iii) administration by community health workers. To enable robust national decision making about the introduction of MR-MAPs and successful implementation, global and national evidence on feasibility and acceptability of MR-MAPs should be generated. To prepare for the potential introduction of MR-MAPs, immunization programmes should evaluate their immunization policies based on their preferred use cases and modify them if needed, for example, to enable community health workers to administer vaccines, along with making programmatic adjustments to waste management and training. Conclusions : MR-MAPs have the potential to reduce key barriers to MR delivery. Yet, their future impact depends on the ability of global stakeholders to steer the development of MR-MAPs to be responsive to country needs and preferences. The generation of evidence to enable robust decision making, timely modification of vaccine policies, and addressing programmatic considerations will be key to successful uptake.

Background: Gait speed is associated with a higher prevalence of balance disorders in older adults residing at high altitudes. This study investigated this association in older adults from 12 high-altitude Andean Peruvian communities., Methods: We performed a secondary data analysis from an analytical cross-sectional study of adults &gt;60 years of age, residing in 12 high-altitude Andean Peruvian communities, enrolled between 2013 and 2019. The exposure and outcome variables were gait speed (categorized in tertiles), and balance disorders (defined as a functional reach value of ≤20.32 cm), respectively. We built generalized linear models of the Poisson family with a logarithmic link function and robust variances, and estimated crude prevalence ratios (cPR) and adjusted prevalence ratios (aPR) with 95% confidence intervals (CIs)., Results: We analyzed 418 older adults; 38.8% (n=162) were male, and the mean age was 73.2±6.9 years. The mean gait speed and functional reach were 0.66±0.24 m/s and 19.9±6.48 cm, respectively. In the adjusted regression model, the intermediate (aPR=1.88; 95% CI, 1.39-2.55; p&lt;0.001) and low (aPR=2.04; 95% CI, 1.51-2.76; p&lt;0.001) tertiles of gait speed were associated with a higher prevalence of balance disorders., Conclusion: The intermediate and low tertiles of gait speed were associated with a higher prevalence of balance disorders among older adult residents of 12 high-altitude Andean communities. We recommend further research on the behavior of this association to propose interventions for these vulnerable groups and reduce the impact of geriatric conditions.

Since the World Health Assembly (WHA) in 2012 endorsed the Global Vaccine Action Plan (GVAP), which included regional measles and rubella elimination goals by 2020, global progress towards verification of measles and rubella elimination has been incremental. Even though the 2020 elimination goals were not achieved, commitment towards achieving measles and rubella elimination has been firmly established in the Immunization Agenda 2030 (IA2030) and the Measles and Rubella Strategic Framework (MRSF) 2021-2030. In 2023, the six Regional Verification Commissions for measles and rubella elimination (RVCs) reviewed data as of 31 December 2022 and confirmed that 82 (42%) Member States have been verified for measles elimination, and 98 (51%) Member States have been verified for rubella elimination. The six RVCs are composed of independent public health and immunization experts who are well-placed to support accelerating measles and rubella elimination. RVCs should be leveraged not only to review elimination documents but also to advocate for and champion public health programming that supports measles and rubella activities. The verification of elimination process is one of many tools that should be deployed to reinforce and accelerate efforts towards achieving a world free of measles and rubella.