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We design an adaptive virtual element method (AVEM) of lowest order over triangular meshes with hanging nodes in 2d, which are treated as polygons. AVEM hinges on the stabilization-free a posteriorierror estimators recently derived in Beirão da Veiga et al.(2023, Adaptive VEM: stabilization-free a posteriorierror analysis and contraction property. SIAM J. Numer. Anal., 61, 457–494). The crucial property, which also plays a central role in this paper, is that the stabilization term can be made arbitrarily small relative to the a posteriorierror estimators upon increasing the stabilization parameter. Our AVEM concatenates two modules, GALERKINand DATA. The former deals with piecewise constant data and is shown in the above article to be a contraction between consecutive iterates. The latter approximates general data by piecewise constants to a desired accuracy. AVEM is shown to be convergent and quasi-optimal, in terms of error decay versus degrees of freedom, for solutions and data belonging to appropriate approximation classes. Numerical experiments illustrate the interplay between these two modules and provide computational evidence of optimality.

This paper presents the experimental observation of nano-material and biopolymer additives on expansive pavement subgrade. Nanomaterials, including nano-lime and nano-silica, as well as biopolymer chitosan from shrimp shells, are used. The experimental methods to inspect the characteristics of improved soils are implemented. California Bearing Ratio (CBR) and swelling test are conducted to investigate the strength characteristics of the improved soil. The observations through several tests such as potential hydrogen (pH), scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray fluorescence (XRF), and cation exchange capacity (CEC) were conducted to visualise the soil microstructure improvement under additive mixtures. The results showed that adding nano-materials with biopolymers led to a significant increase in soil CBR values and a decrease in swelling values. Additionally, microstructure testing confirmed the formation of nano-materials with biopolymers, validating the improvement in soil strength. The pH is also essential to ensure that the chemical improves soil characteristics.

The Child Health and Mortality Prevention Surveillance (CHAMPS) Network programme undertakes post-mortem minimally invasive tissue sampling (MITS), together with collection of ante-mortem clinical information, to investigate causes of childhood deaths across multiple countries. We aimed to evaluate the overall contribution of pneumonia in the causal pathway to death and the causative pathogens of fatal pneumonia in children aged 1–59 months enrolled in the CHAMPS Network.

AbstractPrivately produced safe debt is designed so that there is no adverse selection in trade. But in some macro states—here, the onset of the pandemic—it becomes profitable for some agents to produce private information, and then agents face adverse selection when they trade the debt (i.e., it becomes information sensitive). We empirically study these adverse selection dynamics in a very important asset class, collateralized loan obligations (CLOs), which finance loans to below-investment-grade firms. We decompose the bid-ask spreads on the AAA bonds of CLOs into a component reflecting dealer bank balance sheet costs and the adverse selection component. (JEL D22, D82, E44, G12, G14, G32)

Factitious hypoglycemia is a factitious disorder according to the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), referring to intentionally covertly induced hypoglycemia, with potentially severe consequences. Knowledge of factitious hypoglycemia relies on case reports, and evidence-based information and guidelines are lacking. Diagnosing factitious hypoglycemia in insulin-treated diabetic persons is therefore challenging and often requires a long and costly process. Moreover, the typical metrics proposed to differentiate insulin-induced factitious hypoglycemia from insulinoma (i.e., high insulin and low C-peptide versus high insulin and high C-peptide, respectively) are not always applicable, depending on whether the insulin quantification method can detect the insulin analog. When factitious hypoglycemia is suspected, an emerging trend from recent publications advocates a combination of two insulin quantification methods with different cross-reactivity for insulin analogs, early on in the diagnostic process.

BackgroundThe current standard of care for tetanus prophylaxis management in patients with open wounds likely results in overtreatment and unnecessary costs. Point-of-care immunochromatographic tests, known as Tetanus Quick Sticks (TQS), have been developed to qualitatively measure tetanus immunoglobulin levels. Multiple studies advocate their use in EDs. We aim to evaluate the diagnostic accuracy and cost-effectiveness of TQS to assess their relevance in frontline emergency care.MethodsA systematic review was undertaken following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A literature search was conducted in MEDLINE, Embase, Global Health, The Health Management Information Consortium and The Cochrane Library. Studies were eligible if sensitivity, specificity or cost-efficacy of TQS was reported. At least two authors independently assessed and extracted data from each study. A meta-analysis was conducted to evaluate summary sensitivity and specificity estimates for TQS.Results12 studies were suitable for inclusion (n=1 662 865 participants): 1 modelling and 11 prospective observational cohort studies. Eight studies assessed diagnostic accuracy; the summary estimate for sensitivity was 90% (95% CI, 89% to 90%) with specificity 97% (95% CI, 95% to 100%). Six studies investigated cost-efficacy, reporting lower healthcare costs when using TQS instead of the current method of vaccination history, due to a decrease in unnecessary tetanus vaccine and immunoglobulin administration. Based on the current NHS supply chain data, TQS use could save £173.05 per tetanus-prone patient.ConclusionTQS could confer the greatest cost savings if used in combination with vaccination history in patients with tetanus-prone wounds. A quality assurance process is recommended prior to implementation of TQS in EDs.

Carriage of vaccine-type (VT) and antimicrobial non-susceptible pneumococci in Mozambique dropped quickly after 10-valent pneumococcal conjugate vaccine (PCV10) introduction, especially in HIV-uninfected children. However, VT carriage remained common among both HIV-uninfected and HIV-infected children 3 years after PCV10 introduction, indicating ongoing community transmission.

Objectives Widespread global transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus causing coronavirus disease 2019 (COVID-19), continues. Many questions remain about asymptomatic or atypical infections and transmission dynamics. We used comprehensive contact tracing of the first 2 confirmed patients in Illinois with COVID-19 and serologic SARS-CoV-2 antibody testing to determine whether contacts had evidence of undetected COVID-19.Methods Contacts were eligible for serologic follow-up if previously tested for COVID-19 during an initial investigation or had greater-risk exposures. Contacts completed a standardized questionnaire during the initial investigation. We classified exposure risk as high, medium, or low based on interactions with 2 index patients and use of personal protective equipment (PPE). Serologic testing used a SARS-CoV-2 spike enzyme-linked immunosorbent assay on serum specimens collected from participants approximately 6 weeks after initial exposure to either index patient. The 2 index patients provided serum specimens throughout their illness. We collected data on demographic, exposure, and epidemiologic characteristics.Results Of 347 contacts, 110 were eligible for serologic follow-up; 59 (17% of all contacts) enrolled. Of these, 53 (90%) were health care personnel and 6 (10%) were community contacts. Seventeen (29%) reported high-risk exposures, 15 (25%) medium-risk, and 27 (46%) low-risk. No participant had evidence of SARS-CoV-2 antibodies. The 2 index patients had antibodies detected at dilutions >1:6400 within 4 weeks after symptom onset.Conclusions In serologic follow-up of the first 2 known patients in Illinois with COVID-19, we found no secondary transmission among tested contacts. Lack of seroconversion among these contacts adds to our understanding of conditions (ie, use of PPE) under which SARS-CoV-2 infections might not result in transmission and demonstrates that SARS-CoV-2 antibody testing is a useful tool to verify epidemiologic findings.

We have recently described a new potential use for Langmuir–Blodgett films of surfactants containing redox-inert metal ions in the inhibition of corrosion and have shown good qualitative results for both iron and aluminum surfaces. In this study we proceed to quantify electrochemically the viability of gallium(III)- and zinc(II)-containing metallosurfactants [GaIII(LN2O3)] (1) and [ZnII(LN2O2)H2O] (2) as mitigators for iron corrosion in saline and acidic media. We evaluate their charge transfer suppression and then focus on potentiodynamic polarization and impedance spectroscopy studies, including detailed SEM data to interrogate their metal dissolution/oxygen reduction rate mitigation abilities. Both complexes show some degree of mitigation, with a more pronounced activity in saline than in acidic medium.

ABSTRACTMaternal vaccination coverage remains suboptimal globally and is lowest in low- and middle-income countries. Attitudes toward maternal vaccines have been characterized in middle-high income settings, however data from African countries are limited. We assessed drivers and barriers of vaccine acceptance among pregnant women in Kenya. We conducted a cross-sectional survey among pregnant women aged 15–49 y. We enrolled a convenience sample of women presenting for antenatal care at seven health-care facilities in four diverse counties (Nairobi, Mombasa, Marsabit, Siaya) of Kenya and from the community in two counties (Nairobi, Siaya). We described frequencies of socio-demographic characteristics of participants and their knowledge, attitudes, and beliefs regarding maternal vaccination. We enrolled 604 pregnant women with a median age of 26.5 y, of whom 48.2% had primary education or less. More than 95% agreed that maternal vaccines are “important for my health” and that getting vaccinated is “a good way to protect myself from disease”. The most commonly cited reason in favor of maternal vaccination was disease prevention (53.2%). Fear of side effects to mother/baby (15.1%) was the most frequently reported potential barrier. Influenza vaccine is not in routine use in Kenya; however, 77.8% reported willingness to accept influenza vaccination during pregnancy. Maternal vaccination is well accepted among Kenyan pregnant women. We identified the provision of adequate vaccine information and addressing safety concerns as opportunities to improve maternal vaccine uptake. The expressed willingness to receive a vaccine not currently in routine use bodes well for implementation of new maternal vaccines in Kenya.

Coronavirus disease 2019 (COVID-19) is a disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), first detected in China in December, 2019. In January, 2020, state, local, and federal public health agencies investigated the first case of COVID-19 in Illinois, USA.

Our ongoing efforts to design metallosurfactants capable of directional electron transport led to pondering on the effects of peripheral changes, and the development of 3d5FeIIIsystems where iodo groups replace the usual tert-butyl groups attached to phenylenediamine-bridged phenolate donors. We present the results for two newly designed metallosurfactants, namely, [FeIII(L1)Cl] (1)and [FeIII(L2)Cl] (2), where 1incorporates shorter hydrophilic alkoxy chains than 2. These species had their electronic and electrochemical properties evaluated by experimental and computational methods. We also considered ancillary changes, such as subphase polarity effects on their interfacial properties of Pockels-Langmuir monolayer films on water and Langmuir–Blodgett monolayer films on gold electrodes, evaluated by multiple surface-dedicated methods and probed for directional electron transfer in Au|LB|Au and Au|LB|EGaIn junctions, prior to comparison to the previously published t-Bu-substituted standard [FeIII(LtBu)Cl] (3). These modifications led to significant modulation of metal-based SOMO energy levels toward the Fermi energy levels of the electrode from 1.0 eV in 3to ca. 0.5 eV in 1and 2, which result in better rectification ratios (RR = [I at – V/I at + V]) than those for 3.

A series of pyridine- and phenol-based ruthenium(II)-containing amphiphiles with bidentate ligands of the following types are reported: [(LPyI)RuII(bpy)2](PF6)2(1), [(LPyA)RuII(bpy)2](PF6)2(2), [(LPhBuI)RuII(bpy)2](PF6) (3), and [(LPhClI)RuII(bpy)2](PF6) (4). Species 1and 2are obtained by treatment of [Ru(bpy)2Cl2] with the ligands LPyI(N-(pyridine-2-ylmethylene)octadecan-1-amine) and LPyA(N-(pyridine-2-ylmethyl)octadecan-1-amine). The imine species 3and 4are synthesized by reaction of [Ru(bpy)2(CF3SO3)2] with the amine ligands HLPhBuA(2,4-di-tert-butyl-6-((octadecylamino)methyl)phenol), and HLPhClA(2,4-dichloro-6-((octadecylamino)methyl)phenol). Compounds 1−4are characterized by means of electrospray ionization (ESI+) mass spectrometry, elemental analyses, as well as electrochemical methods, infrared and UV−visible absorption and emission spectroscopies. The cyclic voltammograms (CVs) of 1−2are marked by two successive processes around −1.78 and −2.27 V versus Fc+/Fc attributed to bipyridine reduction. A further ligand-centered reductive process is seen for 1. The RuII/RuIIIcouple appears at 0.93 V versus Fc+/Fc. The phenolato-containing 3and 4species present relatively lower reduction potentials and more reversible redox behavior, along with RuII/IIIand phenolate/phenoxyl oxidations. The interpretation of observed redox behavior is supported by density functional theory (DFT) calculations. Complexes 1−4are surface-active as characterized by compression isotherms and Brewster angle microscopy. Species 1and 2show collapse pressures of about 29−32 mN·m−1, and are strong candidates for the formation of redox-responsive monolayer films.

ABSTRACTBackgroundReliable mortality data are important for evaluating the impact of health interventions. However, data on mortality patterns among populations living in urban informal settlements are limited.ObjectivesTo examine the mortality patterns and trends in an urban informal settlement in Kibera, Nairobi, Kenya,MethodsUsing data from a population-based surveillance platform we estimated overall and cause-specific mortality rates for all age groups using person-year-observation (pyo) denominators and using Poisson regression tested for trends in mortality rates over time. We compared associated mortality rates across groups using incidence rate ratios (IRR). Assignment of probable cause(s) of death was done using the InterVA-4 model.ResultsWe registered 1134 deaths from 2009 to 2018, yielding a crude mortality rate of 4.4 (95% Confidence Interval [CI]4.2–4.7) per 1,000 pyo. Males had higher overall mortality rates than females (incidence rate ratio [IRR], 1.44; 95% CI, 1.28–1.62). The highest mortality rate was observed among children aged < 12 months (41.5 per 1,000 pyo; 95% CI 36.6–46.9). All-cause mortality rates among children < 12 months were higher than that of children aged 1–4 years (IRR, 8.5; 95% CI, 6.95–10.35). The overall mortality rate significantly declined over the period, from 6.7 per 1,000 pyo (95% CI, 5.7–7.8) in 2009 to 2.7 (95% CI, 2.0–3.4) per 1,000 pyo in 2018. The most common cause of death was acute respiratory infections (ARI)/pneumonia (18.1%). Among children < 5 years, the ARI/pneumonia deaths rate declined significantly over the study period (5.06 per 1,000 pyo in 2009 to 0.61 per 1,000 pyo in 2018; p = 0.004). Similarly, death due to pulmonary tuberculosis among persons 5 years and above significantly declined (0.98 per 1,000 pyo in 2009 to 0.25 per 1,000 pyo in 2018; p = 0.006).ConclusionsOverall and some cause-specific mortality rates declined over time, representing important public health successes among this population.

The continuous growth of the electric vehicles market and the increasing environmental awareness impose to search for innovative solutions to reuse the exhausted vehicle batteries in different applications. One of the main problems of second-life batteries is the very high mismatch among their cell capacities which reduces the overall battery performance. The mismatch effect can be overcome by using dynamic equalization. This technique aims to keep balanced as much as possible the State of Charge of the cells during the battery operation, i.e. in both the charge and discharge phases. In order to do this, the dynamic equalization approach requires a high-current active energy balancing system able to move a quantity of charge among the battery cells much higher than the active balancing circuits sometimes used in first-life batteries. The use of a high equalization current increases the design complexity of the balance system.

We propose and analyze an hp-adaptive DG–FEM algorithm, termed $$\varvec {hp}$$hp-ADFEM, and its one-dimensional realization, which is convergent, instance optimal, and h- and p-robust. The procedure consists of iterating two routines: one hinges on Binev’s algorithm for the adaptive hp-approximation of a given function, and finds a near-best hp-approximation of the current discrete solution and data to a desired accuracy; the other one improves the discrete solution to a finer but comparable accuracy, by iteratively applying Dörfler marking and hrefinement.

We have prepared the amphiphilic molecular catalyst [CoIII(LOC18)(pyrr)2]ClO4(1), where LOC18is the deprotonated form of N,N′-[4,5-bis(octadecyloxy)-1,2-phenylene]dipicolinamide. Species 1can be anchored onto a carbon black support to yield the assembly 1@CB, which can catalyze water oxidation at an affordable onset overpotential of 0.32 V, with a current density of 10 mA/cm2at 0.37 V. Moreover, 1@CBdisplays TOF = 3850 h–1. A mechanism is proposed based on the experimental and density-functional-theory-calculated data.

ABSTRACTIn Italy, the phenomenon of vaccine hesitancy has increased with time and represents a complex problem that requires a continuous monitoring. Misinformation on media and social media seems to be one of the determinants of the vaccine hesitancy since, for instance, 42.8 percent of Italian citizens used the internet to obtain vaccine information in 2016.This article reports a quantitative analysis of 560 YouTube videos related to the link between vaccines and autism or other serious side effects on children.The analysis revealed that most of the videos were negative in tone and that the annual number of uploaded videos has increased during the considered period, that goes from 27 December 2007 to 31 July 2017, with a peak of 224 videos in the first seven months of 2017.These findings suggest that the public institutions should be more engaged in establishing a web presence in order to provide reliable information, answers, stories, and videos so to respond to questions of the public about vaccination. These actions could be useful to allow citizens to make informed decisions about vaccines so to comply with vaccination regulations.

We present a multigrid algorithm for the solution of the linear systems of equations stemming from the p-version of the virtual element discretization of a two-dimensional Poisson problem. The sequence of coarse spaces are constructed decreasing progressively the polynomial approximation degree of the virtual element space, as in standard p-multigrid schemes. The construction of the interspace operators relies on auxiliary virtual element spaces, where it is possible to compute higher order polynomial projectors. We prove that the multigrid scheme is uniformly convergent, provided the number of smoothing steps is chosen sufficiently large. We also demonstrate that the resulting scheme provides a uniform preconditioner with respect to the number of degrees of freedom that can be employed to accelerate the convergence of classical Krylov-based iterative schemes. Numerical experiments validate the theoretical results.

•The use of Unmanned Aerial Vehicle (UAV) for pavement condition survey is expected to minimize or even replace conventional road condition surveys in the field.•Photos from UAV are produced into 2D and 3D models as visual media for assessing pavement condition using the Pavement Condition Index (PCI) and Surface Distress Index (SDI) methods.•The level of accuracy of pavement distress in the model against the results of manual measurements in the field ranges from 75 – 98%.•Mean square error and coefficient of determination, as parameters to compare PCI and SDI method, shows the best-fit condition when assessing pavement condition using UAV.

The conventional approach in transport planning aims at the expansion of road transport infrastructure to cope with the increasing transport demand. However, this car-based planning approach not only fails to fulfill the mobility needs due to the limited space available for new road infrastructure leading thus to the vicious circle of traffic congestion, but also contributes to the exacerbation of phenomena such as air pollution, climate change, traffic noise and the degradation of the urban environment. In order to reduce these impacts, contemporary transport planning suggests the paradigm shift from private car to more sustainable transport modes such as walking. Experts consider walking as one of the fastest and most time-reliable transport modes for short-distance trips, especially within central areas. Despite the indisputable advantages of walking, people are often discouraged due to the poor condition of the provided infrastructure for pedestrians and of the surrounding environment. Hence, a major precondition in the contemporary planning comprises the systematic assessment of the walking environment and the comprehensive evaluation of pedestrian infrastructure. Towards this direction the objective of the present paper is the discussion of the contribution of walkability audits as a tool for the monitoring, evaluation and improvement of the walking conditions in an urban area. The paper includes the analysis of the methodology and the results from a walkability audit survey which was conducted in the framework of the city’s recent Urban Mobility Study along the footpaths of the city centre of Serres, Greece and indicates the appropriate interventions for the improvement of walking conditions in the study area.