Influence of Crystallographic Structure and Metal Vacancies on the Oxygen Evolution Reaction Performance of Ni-based Layered Hydroxides.

Nickel-based layered hydroxides (LHs) are a family of efficient electrocatalysts for the alkaline oxygen evolution reaction (OER). Nevertheless, fundamental aspects such as the influence of the crystalline structure and the role of lattice distortion of the catalytic sites remain poorly understood and typically muddled. Herein, we carried out a comprehensive investigation on ɑ-LH, ß-LH and layered double hydroxide (LDH) phases by means of structural, spectroscopical, in-silico and electrochemical studies, which suggest the key aspect exerted by Ni-vacancies in the ɑ-LH structure. Density functional theory (DFT) calculations and X-ray absorption spectroscopy (XAS) confirm that the presence of Ni-vacancies produces acute distortions of the electroactive Ni sites (reflected as the shortening of the Ni-O distances and changes in the O-Ni-O angles), triggering the appearance of Ni localised electronic states on the Fermi level, reducing the Egap, and consequently, increasing the reactivity of the electroactive sites in the ɑ-LH structure. Furthermore, post-mortem Raman and XAS measurements unveil its transformation into a highly reactive oxyhydroxide-like phase that remains stable under ambient conditions. Hence, this work pinpoints the critical role of the crystalline structure as well as the electronic properties of LH structures on their inherent electrochemical reactivity towards OER catalysis. We envision Ni-based ɑ-LH as a perfect platform for hosting trivalent cations, closing the gap toward the next generation of benchmark efficient earth-abundant electrocatalysts.

Novel side chain functionalized polystyrene/O-PBI blends with high alkaline stability for anion exchange membrane water electrolysis (AEMWE).

We report the synthesis of a polystyrene-based anion exchange polymer bearing the cationic charge at a C6-spacer. The polymer is prepared by a functionalized monomer strategy. First, a copper halide catalyzed C-C coupling reaction between a styryl Grignard and 1,6-dibromohexane is applied, followed by quaternization with N-methylpiperidine and free radical polymerization. The novel polymer is blended with the polybenzimidazole O-PBI to yield mechanically stable blend membranes representing a new class of anion exchange membranes. In this regard, the ratio of the novel anion exchange polymer to O-PBI is varied to study the influence on water uptake and ionic conductivity. Blend membranes with IECs between 1.58 meq. OH- g-1 and 2.20 meq. OH- g-1 are prepared. The latter shows excellent performance in AEMWE, reaching 2.0 A cm-2 below 1.8 V in 1 M KOH at 70 °C, with a minor degradation rate from the start. The blend membranes show no conductivity loss after immersion in 1 M KOH at 85 °C for six weeks indicating high alkaline stability.

Upscaling the urea method synthesis of CoAl layered double hydroxides.

Research on two-dimensional materials is one of the most relevant fields in materials science. Layered double hydroxides (LDHs), a versatile class of anionic clays, exhibit great potential in photocatalysis, energy storage and conversion, and environmental applications. However, its implementation in real-life devices requires the development of efficient and reproducible large-scale synthesis processes. Unfortunately, reliable methods that allow for the production of large quantities of two-dimensional LDHs with well-defined morphologies and high crystallinity are very scarce. In this work, we carry out a scale-up of the urea-based CoAl-LDH synthesis method. We thoroughly study the effects of the mass scale-up (25-fold: up to 375 mM) and the volumetric scale-up (20-fold: up to 2 L). For this, we use a combination of several structural (XRD, TGA, and N2 and CO2 isotherms), microscopic (SEM, TEM, and AFM), magnetic (SQUID), and spectroscopic techniques (ATR-FTIR, UV-vis, XPS, ICP-MS, and XANES-EXAFS). In the case of the volumetric scale-up, a reduction of 45% in the lateral dimensions of the crystals (from 3.7 to 2.0 µm) is observed as the reaction volume increases. This fact is related to modified heating processes affecting the alkalinization rates and, concomitantly, the precipitation, even under recrystallization at high temperatures. In contrast, for the tenfold mass scale-up, similar morphological features were observed and assigned to changes in nucleation and growth. However, at higher concentrations, simonkolleite-like Co-based layered hydroxide impurities are formed, indicating a phase competition during the precipitation related to the thermodynamic stability of the growing phases. Overall, this work demonstrates that it is possible to upscale the synthesis of high-quality hexagonal CoAl-LDH in a reproducible manner. It highlights the most critical synthesis aspects that must be controlled and provides various fingerprints to trace the quality of these materials. These results will contribute to bringing the use of these 2D layered materials closer to reality in different applications of interest.

Crystallographic and Geometrical Dependence of Water Oxidation Activity in Co-Based Layered Hydroxides.

Cobalt-based layered hydroxides (LHs) stand out as one of the best families of electroactive materials for the alkaline oxygen evolution reaction (OER). However, fundamental aspects such as the influence of the crystalline structure and its connection with the geometry of the catalytic sites remain poorly understood. Thus, to address this topic, we have conducted a thorough experimental and in silico study on the most important divalent Co-based LHs (i.e., α-LH, ß-LH, and LDH), which allows us to understand the role of the layered structure and coordination environment of divalent Co atoms on the OER performance. The α-LH, containing both octahedral and tetrahedral sites, behaves as the best OER catalyst in comparison to the other phases, pointing out the role of the chemical nature of the crystalline structure. Indeed, density functional theory (DFT) calculations confirm the experimental results, which can be explained in terms of the more favorable reconstruction into an active Co(III)-based oxyhydroxide-like phase (dehydrogenation process) as well as the significantly lower calculated overpotential across the OER mechanism for the α-LH structure (exhibiting lower Egap). Furthermore, ex situ X-ray diffraction and absorption spectroscopy reveal the permanent transformation of the α-LH phase into a highly reactive oxyhydroxide-like stable structure under ambient conditions. Hence, our findings highlight the key role of tetrahedral sites on the electronic properties of the LH structure as well as their inherent reactivity toward OER catalysis, paving the way for the rational design of more efficient and low-maintenance electrocatalysts.

Characterization of airborne particulate matter and its toxic and proarrhythmic effects: A case study in Aburrá Valley, Colombia.

Particle matter (PM) is a complex mixture of particles suspended in the air, mainly caused by fuel combustion from vehicles and industry, and has been related to pulmonary and cardiovascular diseases. The Metropolitan Area of Aburrá Valley in Colombia is the second most populous urban agglomeration in the country and the third densest in the world, composed of ten municipalities. Examining the physicochemical properties of PM is crucial in comprehending its composition and its effects on human health, as it varies based on the socioeconomic dynamics specific to each city. This study characterized the PM collected from the north, south, and central zones to evaluate its chemical composition and morphology. Different elements such as silicon, carbon, aluminum, potassium, calcium, sodium, iron, magnesium, and copper and the presence of unburned fuel, motor oil, and silicon fibers were identified. In vitro and in silico studies were conducted to evaluate the toxicity of the PM, and it was found that the PM collected from the central zone had the greatest impact on cell viability and caused DNA damage. The in silico study demonstrated that PM has concentration-dependent proarrhythmic effects, reflected in an action potential duration shortening and an increased number of reentries, which may contribute to the development of cardiac arrhythmias. Overall, the results suggest that the size and chemical composition of ambient PM can induce toxicity and play an important role in the generation of arrhythmias.

Colombian Sustainability Perspective on Fused Deposition Modeling Technology: Opportunity to Develop Recycled and Biobased 3D Printing Filaments.

In the context of the preservation of natural resources, researchers show a growing interest in developing eco-friendly materials based on recycled polymers and natural fiber biocomposites to minimize plastic and agroindustrial waste pollution. The development of new materials must be integrated within the circular economy concepts to guarantee sustainable production. In parallel, fused deposition modeling, an additive manufacturing technology, provides the opportunity to use these new materials in an efficient and sustainable manner. This review presents the context of plastics and agro-industrial fiber pollution, followed by the opportunity to give them added value by applying circular economy concepts and implementing these residues to develop new materials for the manufacture of fused deposition modeling 3D printing technique feedstock. Colombian perspective is highlighted since 3D printing technology is growing there, and Colombian biodiversity represents a high reservoir of materials. Also, recycling in Colombia promotes compliance with the 2030 Agenda and the Sustainable Development Goals.

The enduring gap in educational attainment in schizophrenia according to the past 50 years of published research: a systematic review and meta-analysis.

BACKGROUND: Educational attainment is associated with wellbeing and health, but patients with schizophrenia achieve lower levels of education than people without. Several effective interventions can ameliorate this situation. However, the magnitude of the education gap in schizophrenia and its change over time are unclear. We aimed to reconstruct the trajectories of educational attainment in patients with schizophrenia and, if reported, their healthy comparator controls. METHODS: We did a systematic review and meta-analysis including all studies reporting on patients with schizophrenia (of mean age ≥18 years) and describing the number of years of education of the participants, with or without healthy controls. There were no other design constraints on studies. We excluded studies that included only patients with other schizophrenia spectrum disorders and studies that did not specify the number of years of education of the participants. 22 reviewers participated in retrieving data from a search in PubMed and PsycINFO (Jan 1, 1970, to Nov 24, 2020). We estimated the birth date of participants from their mean age and publication date, and meta-analysed these data using random-effects models, focusing on educational attainment, the education gap, and changes over time. The primary outcome was years of education. The protocol was registered on PROSPERO (CRD42020220546). FINDINGS: From 32 593 initial references, we included 3321 studies reporting on 318 632 patients alongside 138 675 healthy controls (170 941 women and 275 821 men from studies describing sex or gender; data on ethnicity were not collected). Patients' educational attainment increased over time, mirroring that of controls. However, patients with schizophrenia in high-income countries had 19 months less education than controls (-1·59 years, 95% CI -1·66 to -1·53; p<0·0001), which is equivalent to a Cohen's d of -0·56 (95% CI -0·58 to -0·54) and implies an odds ratio of 2·58 for not completing 12 years of education (ie, not completing secondary education) for patients compared with controls. This gap remained stable throughout the decades; the rate of change in number of total years of education in time was not significant (annual change: 0·0047 years, 95% CI -0·0005 to 0·0099; p=0·078). For patients in low-income and middle-income countries, the education gap was significantly smaller than in high-income countries (smaller by 0·72 years, 0·85 to 0·59; p<0·0001), yet there was evidence that this gap was widening over the years, approaching that of high-income countries (annual change: -0·024 years, -0·037 to -0·011; p=0·0002). INTERPRETATION: Patients with schizophrenia have faced persistent inequality in educational attainment in the last century, despite advances in psychosocial and pharmacological treatment. Reducing this gap should become a priority to improve their functional outcomes. FUNDING: Ciencia y Tecnología para el Desarrollo (CYTED) to the Latin American Network for the Study of Early Psychosis (ANDES).

Gender, age and geographical representation over the past 50 years of schizophrenia research.

Previous studies have suggested that subjects participating in schizophrenia research are not representative of the demographics of the global population of people with schizophrenia, particularly in terms of gender and geographical location. We here explored if this has evolved throughout the decades, examining changes in geographical location, gender and age of participants in studies of schizophrenia published in the last 50 years. We examined this using a meta-analytical approach on an existing database including over 3,000 studies collated for another project. We found that the proportion of studies and participants from low-and-middle income countries has significantly increased over time, with considerable input from studies from China. However, it is still low when compared to the global population they represent. Women have been historically under-represented in studies, and still are in high-income countries. However, a significantly higher proportion of female participants have been included in studies over time. The age of participants included has not changed significantly over time. Overall, there have been improvements in the geographical and gender representation of people with schizophrenia. However, there is still a long way to go so research can be representative of the global population of people with schizophrenia, particularly in geographical terms.

Atrial proarrhythmic effect of lead as one of the PM10 metal components of air pollution. An in-silico study.

Particulate matter (PM) is considered the most severe environmental pollution problem due to its serious effects on human health associated with an increased risk of cardiovascular morbidity and mortality. In this work, a physicochemical characterization of PM10 from the city of Medellin was developed. The results evince that lead (Pb) is one of the most abundant elements since it is present in all analyzed samples. Therefore, Pb was chosen to perform an in-silico study to assess its effects on atrial arrhythmias generation. For this purpose, we developed a model representing the Pb2+ blocking effect on the L-type calcium channel. This formulation was incorporated in a human atrial cell mathematical model and in 2D and 3D models of human atria. The simulations showed a proarrhythmic effect at high Pb2+ concentrations, through shortening of action potential duration inducing the generation of reentrant activity and atrial flutter. The results contribute to the knowledge about the cardiac physiopathological processes, triggered by lead as one of the main PM10 metal components of air pollution, that yields the generation of arrhythmias.

Development and Characterization of a 3D Printed Cocoa Bean Shell Filled Recycled Polypropylene for Sustainable Composites.

Natural filler-based composites are an environmentally friendly and potentially sustainable alternative to synthetic or plastic counterparts. Recycling polymers and using agro-industrial wastes are measures that help to achieve a circular economy. Thus, this work presents the development and characterization of a 3D printing filament based on recycled polypropylene and cocoa bean shells, which has not been explored yet. The obtained composites were thermally and physically characterized. In addition, the warping effect, mechanical, and morphological analyses were performed on 3D printed specimens. Thermal analysis exhibited decreased thermal stability when cacao bean shell (CBS) particles were added due to their lignocellulosic content. A reduction in both melting enthalpy and crystallinity percentage was identified. This is caused by the increase in the amorphous structures present in the hemicellulose and lignin of the CBS. Mechanical tests showed high dependence of the mechanical properties on the 3D printing raster angle. Tensile strength increased when a raster angle of 0° was used, compared to specimens printed at 90°, due to the load direction. Tensile strength and fracture strain were improved with CBS addition in specimens printed at 90°, and better bonding between adjacent layers was achieved. Electron microscope images identified particle fracture, filler-matrix debonding, and matrix breakage as the central failure mechanisms. These failure mechanisms are attributed to the poor interfacial bonding between the CBS particles and the matrix, which reduced the tensile properties of specimens printed at 0°. On the other hand, the printing process showed that cocoa bean shell particles reduced by 67% the characteristic warping effect of recycled polypropylene during 3D printing, which is advantageous for 3D printing applications of the rPP. Thereby, potential sustainable natural filler composite filaments for 3D printing applications with low density and low cost can be developed, adding value to agro-industrial and plastic wastes.

Síndrome de Miescher-Melkersson-Rosenthal: Presentación de tres casos y revisión de la literatura / Miescher-Melkersson-Rosenthal Syndrome: Three cases reports and literature review

RESUMEN El síndrome de Miescher-Melkerson-Rosenthal es una condición clínica poco frecuente caracterizada por un edema orofacial episódico, paresia facial periférica recurrente, lengua geográfica (lingua plicata) y granulomas en biopsia de piel o labial. Se ha reportado más frecuentemente en mujeres, y su incidencia es probablemente subestimada por el desconocimiento del síndrome, su presentación clínica incompleta y la plétora de diagnósticos diferenciales. Se debe considerar en pacientes que presenten al menos dos de las cuatro características mencionadas. Su tratamiento, con esteroides vía oral, está dirigido a los episodios de edema orofacial y/o paresia facial. A continuación se describen tres casos del síndrome valorados en el servicio de neurología de la Fundación Cardioinfantil y se presenta una breve revisión de la literatura.

SUMMARY Miescher-Melkerson-Rosenthal syndrome is an uncommon clinical condition characterized by episodic orofacial oedema, recurrent peripheral facial paralysis, geographic tongue (lingua plicata) and granulomas in skin or labial biopsy. It is reported more frequently in women, and its incidence is probably underestimated due to lack of knowledge of the syndrome, incomplete clinical presentation and the plethora of differential diagnosis. It should be considered in patients with at least two of the four mentioned characteristics. Its treatment, with oral steroids, is directed at the episodes of orofacial oedema and/or the facial paralysis. We described three cases of the syndrome seen at the Fundacion Cardioinfantil's neurology service and present a short review of the literature.

Development and Characterization of Rice Husk and Recycled Polypropylene Composite Filaments for 3D Printing.

Nowadays the use of natural fiber composites has gained significant interest due to their low density, high availability, and low cost. The present study explores the development of sustainable 3D printing filaments based on rice husk (RH), an agricultural residue, and recycled polypropylene (rPP) and the influence of fiber weight ratio on physical, thermal, mechanical, and morphological properties of 3D printing parts. Thermogravimetric analysis revealed that the composite's degradation process started earlier than for the neat rPP due to the lignocellulosic fiber components. Mechanical tests showed that tensile strength increased when using a raster angle of 0° than specimens printed at 90°, due to the weaker inter-layer bonding compared to in-layer. Furthermore, inter layer bonding tensile strength was similar for all tested materials. Scanning electron microscope (SEM) images revealed the limited interaction between the untreated fiber and matrix, which led to reduced tensile properties. However, during the printing process, composites presented lower warping than printed neat rPP. Thus, 3D printable ecofriendly natural fiber composite filaments with low density and low cost can be developed and used for 3D printing applications, contributing to reduce the impact of plastic and agricultural waste.

3D-printed microplate inserts for long term high-resolution imaging of live brain organoids.

BACKGROUND: Organoids are a reliable model used in the study of human brain development and under pathological conditions. However, current methods for brain organoid culture generate tissues that range from 0.5 to 2 mm of size, which need to be constantly agitated to allow proper oxygenation. The culture conditions are, therefore, not suitable for whole-brain organoid live imaging, required to study developmental processes and disease progression within physiologically relevant time frames (i.e. days, weeks, months). RESULTS: Here we designed 3D-printed microplate inserts adaptable to standard 24 multi-well plates, which allow the growth of multiple organoids in pre-defined and fixed XYZ coordinates. This innovation facilitates high-resolution imaging of whole-cerebral organoids, allowing precise assessment of organoid growth and morphology, as well as cell tracking within the organoids, over long periods. We applied this technology to track neocortex development through neuronal progenitors in brain organoids, as well as the movement of patient-derived glioblastoma stem cells within healthy brain organoids. CONCLUSIONS: This new bioengineering platform constitutes a significant advance that permits long term detailed analysis of whole-brain organoids using multimodal inverted fluorescence microscopy.

Terapia endovascular para el manejo del infarto cerebral isquémico agudo durante la pandemia por covid-19 / Endovascular therapy for the management of Acute Ischemic Stroke During the COVID-19 Pandemic

RESUMEN PROPÓSITO: La pandemia mundial por covid-19 ha impuesto nuevos retos para la atención de pacientes con infarto cerebral con oclusión de gran vaso, el tratamiento endovascular con trombectomía mecánica es la elección para estos casos. Las recomendaciones que se presentan buscan mantener la eficacia, la celeridad y la seguridad de la intervención siguiendo las nuevas medidas de bioseguridad. METODOLOGÍA: Revisión no sistemática de la literatura de manejo endovascular para el infarto cerebral en época pre covid-19 y durante la pandemia por covid-19. Los aspectos de la intervención, que a juicio de los autores se modificaron, se presentan en forma de recomendaciones narrativas. RESULTADOS: Se identificaron tres fases en el manejo endovascular del infarto cerebral: preintervención, intervención y postintervención. En la primera se incluyen los temas de selección del candidato, la tamización para covid-19, el consentimiento informado, la notificación-preparación del equipo y la modalidad anestésica. En las otras dos fases se hacen recomendaciones generales. Por último, se identifican puntos importantes para la toma de decisiones en el manejo endovascular del infarto cerebral. CONCLUSIÓN: Las recomendaciones pretenden facilitar la adaptación de los protocolos, evitar retrasos y mantener la seguridad de la intervención endovascular en pacientes con infarto cerebral con oclusión de gran vaso candidatos a trombectomía mecánica en época de covid-19.

SUMMARY PURPOSE: The global pandemic of COVID-19 has imposed new challenges for the attention of patients with ischemic stroke and large vessel occlusion. Endovascular treatment with mechanical thrombectomy is the therapy of choice for these patients. The recommendations intend to maintain the efficacy, times and safety of the intervention following the new biosafety measures. METHODOLOGY: A non-systematic review of the literature on endovascular management for ischemic stroke in the pre-COVID-19 period and during the COVID-19 pandemic. The aspects of the intervention, modified in the author's opinion, are presented in the form of narrative recommendations. RESULTS: Three phases were identified in the endovascular management for cerebral infarction: Pre-intervention, intervention, and post-intervention. The first one includes candidate selection, screening for COVID-19, informed consent, notification-preparation of the team/suite and anesthetic modality. For the other two phases general recommendations were developed. Finally, we identified key points for decision-making in the endovascular management of ischemic stroke. CONCLUSION: These recommendations pretend to facilitate adaptations of protocols, avoid delays and maintain the safety of endovascular intervention in patients with ischemic stroke with large vessel occlusion candidates for mechanical thrombectomy during COVID-19 pandemic.

Twenty-Four-Hour Ambulatory Blood Pressure Monitoring.

The diagnosis, management, and estimated mortality risk in patients with hypertension have been historically based on clinic or office blood pressure readings. Current evidence indicates that 24-hour ambulatory blood pressure monitoring should be an integral part of hypertension care. The 24-hour ambulatory monitors currently available on the market are small devices connected to the arm cuff with tubing that measure blood pressure every 15 to 30 minutes. After 24 hours, the patient returns, and the data are downloaded, including any information requested by the physician in a diary. The most useful information includes the 24-hour average blood pressure, the average daytime blood pressure, the average nighttime blood pressure, and the calculated percentage drop in blood pressure at night. The most widely used criteria for 24-hour measurements are from the American Heart Association 2017 guidelines and the European Society of Hypertension 2018 guidelines. Two important scenarios described in this document are white coat hypertension, in which patients have normal blood pressures at home but high blood pressures during office visits, and masked hypertension, in which patients are normotensive in the clinic but have high blood pressures outside of the office. The Centers for Medicare and Medicaid Services has made changes in its policy to allow reimbursement for a broader use of 24-hour ambulatory blood pressure monitoring within some specific guidelines. Primary care physicians should make more use of ambulatory blood pressure monitoring, especially in patients with difficult to manage hypertension.

Event marker compliance in actigraphy.

Actigraphy is a versatile tool for evaluating sleep-wake cycles over time in the home-environment. Patients using the Phillips Actiwatch place an event marker when going to sleep and upon awakening. We investigate compliance in pressing the Actiwatch event marker button for patients referred for insomnia, hypersomnia and disorders of circadian rhythm. We retrospectively analysed event markers from 150 patients undergoing actigraphy for 2,117 nights combined. Compliance was evaluated from inspection of actigraphy records, and coded as full or partial. From patient records, a construct called the C-factor, designed to describe poor social resources and chronic unemployment, was used together with age and sex to predict compliance. We found a mean compliance between 54.0% and 76.3% for a median monitoring duration of 14 days. There was an overall insignificant effect of age (p = .081), but when analysed only for females there was a significant effect of 0.56% pr. year (p = .0038). Compliance was higher for women, Cohen's d = 0.65 (p = .01). The C-factor predicts 18.3% (confidence interval 9%-27.5%) lower compliance. Morning and evening compliance are correlated at r = .65. In conclusion, actigraphy event marker compliance is generally moderate or high, with older women exhibiting the highest compliance. C-factor predicts lower compliance, and this pattern may further translate to other circumstances. If compliance is important, clinicians may want to consider the effects of age, sex and C-factor.

One approach to circulation and blood flow in the critical care unit.

Evaluating and managing circulatory failure is one of the most challenging tasks for medical practitioners involved in critical care medicine. Understanding the applicability of some of the basic but, at the same time, complex physiological processes occurring during a state of illness is sometimes neglected and/or presented to the practitioners as point-of-care protocols to follow. Furthermore, managing hemodynamic shock has shown us that the human body is designed to fight to sustain life and that the compensatory mechanisms within organ systems are extraordinary. In this review article, we have created a minimalistic guide to the clinical information relevant when assessing critically ill patients with failing circulation. Measures such as organ blood flow, circulating volume, and hemodynamic biomarkers of shock are described. In addition, we will describe historical scientific events that led to some of our current medical practices and its validation for clinical decision making, and we present clinical advice for patient care and medical training.

Evolving spectrum of diabetic nephropathy.

Diabetes remains an important health issue as more patients with chronic and uncontrolled diabetes develop diabetic nephropathy (DN), which classically presents with proteinuria followed by a progressive decrease in renal function. However, an increasing proportion of DN patients have a decline in kidney function and vascular complications without proteinuria, known as non-proteinuric DN (NP-DN). Despite the increased incidence of NP-DN, few clinical or experimental studies have thoroughly investigated the pathophysiological mechanisms and targeted treatment for this form of DN. In this review, we will examine the differences between conventional DN and NP-DN and consider potential pathophysiological mechanisms, diagnostic markers, and treatment for both DN and NP-DN. The investigation of the pathophysiology of NP-DN should provide additional insight into the cardiovascular factors influencing renal function and disease and provide novel treatments for the vascular complications seen in diabetic patients.