Polymer accumulation in mixed cyanobacterial cultures selected under the feast and famine strategy

In this study, a sequencing batch reactor (SBR), operated with transient carbon availability (feast and famine) and different nutrients loads, was used to select cyanobacteria accumulating poly (3-hydroxyalkanoate) (PHB) and carbohydrates from a mixed wastewater-borne microbial culture. The SBR was operated with 12 h aerobic light and 12 h anaerobic dark phases, evaluating the effect of three different operational conditions consisting on; 1) carbon limitation, 2) carbon and phosphorus limitation and 3) phosphorus limitation. Once a steady state was reached in each operational period of the SBR, part of the biomass was collected and submitted to separate batch tests in order to investigate the maximum PHB and carbohydrates accumulation levels. Batch tests were performed during 24 h of illuminated aerobic condition and 24 h of dark anaerobic condition, while inorganic carbon was constantly present. During the SBR operation, inorganic carbon was mostly used for biomass and carbohydrate production, showing very low PHB accumulation levels (<1%). Notwithstanding, in subsequent batch tests, PHB was accumulated after a complete depletion of nitrogen, reaching almost 4%. Concerning carbohydrates, it was found that phosphorus limitation (with and without carbon limitation) led to a culture mostly dominated by cyanobacteria and higher levels of carbohydrate content (43%–48%) than the culture with carbon limitation and high loads of nitrogen and phosphorus (29%). Such contents were obtained in only 24 h of incubation under aerobic illuminated conditions. Hence, these encouraging results indicate that carbon uptake and the consequent polymers production from cyanobacteria can be enhanced through carbon and nutrient feeding strategiesPeer ReviewedPostprint (author's final draft

Nerve tissue engineering using blends of poly(3-hydroxyalkanoates) for peripheral nerve regeneration

The only types of polyhydroxyalkanoates (PHAs) that have been explored for use in nerve regeneration are poly(3‐hydroxybutyrate), P(3HB), and poly(3‐hydroxybutyrate‐co‐3‐hydroxyhexanoate) (P(3HB‐co‐3HHx)). However, nerve regeneration induced by these PHAs is inferior to that of autologous nerve grafting. The aim of this work was to study novel PHA blends as resorbable biomaterials for the manufacture of nerve guidance conduits. PHA blend films with varying ratios of poly(3‐hydroxyoctanoate)/poly(3‐hydroxybutyrate) (P(3HO)/P(3HB)) were produced using the solvent‐casting method. Neat films of P(3HO) and P(3HB), along with 25:75, 50:50, and 75:25 blend films of P(3HO)/P(3HB), were characterized with respect to chemical, material, and biological properties. On surface analysis, the blends exhibited higher values of roughness compared with the neat films. The differential scanning calorimetry characterization of the blends confirmed that P(3HO) and P(3HB) formed immiscible blends. FTIR and XRD analysis of the blends showed a decrease in crystallinity along with an increase of the proportion of P(3HO) . However, an increase in the stiffness of the blends was observed when the proportion of P(3HB) increased. Although all of the blends were biocompatible with NG108‐15 neuronal cells, the 25:75 P(3HO)/P(3HB) blend showed significantly better support for growth and differentiation of these cells. The mechanical properties of PHA blends correspond to the reported properties of peripheral nerves. Therefore, they could serve as base material for the manufacture of nerve guidance conduits

Instrumentos para la valoración de las necesidades de los familiares de pacientes ingresados en cuidados intensivos: una revisión sistemática

El ingreso de un familiar en una unidad de cuidados intensivos es un evento estresante para los miembros de la familia. Durante ese periodo, la familia padece situaciones de miedo, incertidumbre y cansancio, y dedica toda su atención a la evolución del familiar ingresado. En ese contexto, resulta imprescindible el apoyo y la atención por parte de los profesionales sanitarios mediante la valoración de las necesidades propias de la familia. Existen diversos instrumentos creados para la valoración de dichas necesidades. A través de esta revisión sistemática, se pretende identificar cuáles son esos cuestionarios y analizar críticamente sus características para ofrecer a los profesionales que trabajan en áreas de críticos unos cuestionarios válidos y fiables que puedan utilizar en el abordaje a las familias.The hospitalisation of a family member in an intensive care unit is a stressful event for the rest of the family members. During hospitalisation, the family suffers situations of fear, uncertainty and tiredness, and focuses on the medical evolution of their ill member. In this context, support and attention from health care professionals through the assessment of the needs of the family are crucial. There are different instruments for the assessment of a family’s needs. This systematic review aims to identify these questionnaires and to critically analyse their characteristics, so as to offer professionals valid and reliable questionnaires that they can use when caring for families in critical units

Intervenciones de enfermería en el contexto de la exacerbación de la enfermedad pulmonar obstructiva crónica en atención domiciliaria

Introducción: El tratamiento domiciliario de la exacerbación de la enfermedad pulmonar obstructiva crónica en la fase aguda tiene menor tasa de mortalidad, menor tasa de rehospitalización y menor coste que el tratamiento en el hospital. Además, recibir tratamiento postagudo en el domicilio reduce los reingresos frente a no recibir atención domiciliaria. Objetivo: Analizar la efectividad de las intervenciones de enfermería en el contexto de la exacerbación de la enfermedad pulmonar obstructiva crónica en el ámbito de la atención domiciliaria. Metodología: Se realizó una revisión bibliográfica en las bases de datos Cinahl y Pubmed entre los meses de octubre a diciembre de 2022. Resultados: Se analizaron ocho artículos de las que se identificaron cuatro tipos de intervenciones de enfermería en este ámbito: monitorización, oxigenoterapia, rehabilitación pulmonar y fomento del autocuidado. Estas tuvieron un impacto positivo, menos la oxigenoterapia administrada con ventilación no invasiva que no tubo mejoras estadísticamente significativas. Conclusiones: Este estudio muestra la eficacia de las intervenciones, pero se encontró poca evidencia durante la propia exacerbación de la enfermedad pulmonar obstructiva crónica.Introduction: Home treatment of chronic obstructive pulmonary disease exacerbation in the acute phase has lower mortality rate, lower rehospitalization rate, and lower cost than hospital treatment. In addition, receiving post-acute treatment at home reduces readmissions compared to not receiving home care. Objective: To analyze the effectiveness of nursing interventions in the context of exacerbation of chronic obstructive pulmonary disease in the home care setting.Methodology: A literature review was conducted in the Cinahl and Pubmed databases from October to December 2022. Results: Eight articles were analyzed from which four types of nursing interventions were identified in this setting: monitoring, oxygen therapy, pulmonary rehabilitation and promotion of self-care. These had a positive impact, except for oxygen therapy administered with noninvasive ventilation which did not have statistically significant improvements. Conclusions: This study shows the efficacy of interventions, but little evidence was found during the exacerbation of chronic obstructive pulmonary disease itself

A combined experimental and theoretical study of the supramolecular self-assembly of the natural benzopyran 2,2-dimethyl-3-hydroxy-6-acetyl-chromane and its isomeric benzofuran 10,11-dihydro-10-hydroxytremetone

Epoxidation of 4HMBA, the main metabolite of the medicinal plant Sencecionutans, produces an unstable epoxide eventually giving rise to a mixture of four derivatives, three of them previously reported as natural products. The epoxide product easily undergoes an intra-molecular attack of the phenolic hydroxyl against the epoxide group carbons to produce either a benzofuran or a chromane derivative. When dissolved in methanol-water mixture at room temperature the epoxide is completely solvolyzed to give the corresponding diol (hydrolysis) or vicinal hydroxyl-methoxy (methanolysis) derivative. All the compounds involved in the above reactions were characterized by IR, Raman, H NMR and UV–vis spectroscopies, and by mass spectrometry. Density functional theory (DFT) computations were used to optimize the structure conformations. The optimized structures were further subjected to a Natural Bond Orbital (NBO) and electrostatic potentials analysis. The crystal structures of the title compounds (for short, 3 and 4 respectively) were determined by X-ray diffraction methods. Compound 3 crystallizes in the triclinic P-1 space group with a = 6.4289 (6) Å, b = 8.7120 (6) Å, c = 10.952 (1) Å, α = 92.280 (7)°, β = 95.738 (7)°, γ = 103.973 (7)°, and Z = 2 molecules per unit cell and 4 in the monoclinic P21/c space group with a = 11.2891 (6) Å, b = 9.1902 (4) Å, c = 12.4272 (7) Å. Β = 113.689 (7)°, and Z = 4. In 3 neighboring molecules are linked to each other by OH⋯O (keto) bonds giving rise to a polymeric structure. In 4 the OH group is a bifurcate H-bond donor. It forms a weak intra-molecular OH⋯O (furan) bond and also a much stronger inter-molecular OH⋯O (keto) bond giving rise to a zig-zag polymeric structure. A detailed analysis of the solid state molecular interactions of compounds 3 and 4 has been performed using Hirshfeld surface analysis and their associated 2D fingerprint plots.Instituto de Física La Plat

Cross-species complementation reveals conserved functions for EARLY FLOWERING 3 between monocots and dicots

Plant responses to the environment are shaped by external stimuli and internal signaling pathways. In both the model plant Arabidopsis thaliana (Arabidopsis) and crop species, circadian clock factors are critical for growth, flowering, and circadian rhythms. Outside of Arabidopsis, however, little is known about the molecular function of clock gene products. Therefore, we sought to compare the function of Brachypodium distachyon (Brachypodium) and Setaria viridis (Setaria) orthologs of EARLY FLOWERING 3, a key clock gene in Arabidopsis. To identify both cycling genes and putative ELF3 functional orthologs in Setaria, a circadian RNA-seq dataset and online query tool (Diel Explorer) were generated to explore expression profiles of Setaria genes under circadian conditions. The function of ELF3 orthologs from Arabidopsis, Brachypodium, and Setaria was tested for complementation of an elf3 mutation in Arabidopsis. We find that both monocot orthologs were capable of rescuing hypocotyl elongation, flowering time, and arrhythmic clock phenotypes. Using affinity purification and mass spectrometry, our data indicate that BdELF3 and SvELF3 could be integrated into similar complexes in vivo as AtELF3. Thus, we find that, despite 180 million years of separation, BdELF3 and SvELF3 can functionally complement loss of ELF3 at the molecular and physiological level

Thermodiffusion in multicomponent n-alkane mixtures

Compositional grading within a mixture has a strong impact on the evaluation of the pre-exploitation distribution of hydrocarbons in underground layers and sediments. Thermodiffusion, which leads to a partial diffusive separation of species in a mixture due to the geothermal gradient, is thought to play an important role in determining the distribution of species in a reservoir. However, despite recent progress, thermodiffusion is still difficult to measure and model in multicomponent mixtures. In this work, we report on experimental investigations of the thermodiffusion of multicomponent n-alkane mixtures at pressure above 30 MPa. The experiments have been conducted in space onboard the Shi Jian 10 spacecraft so as to isolate the studied phenomena from convection. For the two exploitable cells, containing a ternary liquid mixture and a condensate gas, measurements have shown that the lightest and heaviest species had a tendency to migrate, relatively to the rest of the species, to the hot and cold region, respectively. These trends have been confirmed by molecular dynamics simulations. The measured condensate gas data have been used to quantify the influence of thermodiffusion on the initial fluid distribution of an idealised one dimension reservoir. The results obtained indicate that thermodiffusion tends to noticeably counteract the influence of gravitational segregation on the vertical distribution of species, which could result in an unstable fluid column. This confirms that, in oil and gas reservoirs, the availability of thermodiffusion data for multicomponent mixtures is crucial for a correct evaluation of the initial state fluid distribution

Adaptive working memory training does not produce transfer effects in cognition and neuroimaging

Despite growing interest in cognitive interventions from academia and industry, it remains unclear if working memory (WM) training, one of the most popular cognitive interventions, produces transfer effects. Transfer effects are training-induced gains in performance in untrained cognitive tasks, while practice effects are improvements in trained task. The goal of this study was to evaluate potential transfer effects by comprehensive cognitive testing and neuroimaging. In this prospective, randomized-controlled, and single-blind study, we administered an 8-week n-back training to 55 healthy middle-aged (50–64 years) participants. State-of-the-art multimodal neuroimaging was used to examine potential anatomic and functional changes. Relative to control subjects, who performed non-adaptive WM training, no near or far transfer effects were detected in experimental subjects, who performed adaptive WM training. Equivalently, no training-related changes were observed in white matter integrity, amplitude of low frequency fluctuations, glucose metabolism, functional and metabolic connectivity. Exploratory within-group comparisons revealed some gains in transfer tasks, which, however, cannot be attributed to an increased WM capacity. In conclusion, WM training produces transfer effects neither at the cognitive level nor in terms of neural structure or function. These results speak against a common view that training-related gains reflect an increase in underlying WM capacity. Instead, the presently observed practice effects may be a result of optimized task processing strategies, which do not necessarily engage neural plasticity

Compact \u3cb\u3e-300 kV\u3c/b\u3e dc Inverted Insulator Photogun With Biased Anode and Alkali-Antimonide Photocathode

This contribution describes the latest milestones of a multiyear program to build and operate a compact −300  kV dc high voltage photogun with inverted insulator geometry and alkali-antimonide photocathodes. Photocathode thermal emittance measurements and quantum efficiency charge lifetime measurements at average current up to 4.5 mA are presented, as well as an innovative implementation of ion generation and tracking simulations to explain the benefits of a biased anode to repel beam line ions from the anode-cathode gap, to dramatically improve the operating lifetime of the photogun and eliminate the occurrence of micro-arc discharges