Polymyxin B-Enriched Exogenous Lung Surfactant: Thermodynamics and Structure.

The use of an exogenous pulmonary surfactant (EPS) to deliver other relevant drugs to the lungs is a promising strategy for combined therapy. We evaluated the interaction of polymyxin B (PxB) with a clinically used EPS, the poractant alfa Curosurf (PSUR). The effect of PxB on the protein-free model system (MS) composed of four phospholipids (diC16:0PC/16:0-18:1PC/16:0-18:2PC/16:0-18:1PG) was examined in parallel to distinguish the specificity of the composition of PSUR. We used several experimental techniques (differential scanning calorimetry, small- and wide-angle X-ray scattering, small-angle neutron scattering, fluorescence spectroscopy, and electrophoretic light scattering) to characterize the binding of PxB to both EPS. Electrostatic interactions PxB-EPS are dominant. The results obtained support the concept of cationic PxB molecules lying on the surface of the PSUR bilayer, strengthening the multilamellar structure of PSUR as derived from SAXS and SANS. A protein-free MS mimics a natural EPS well but was found to be less resistant to penetration of PxB into the lipid bilayer. PxB does not affect the gel-to-fluid phase transition temperature, Tm, of PSUR, while Tm increased by ∼+ 2 °C in MS. The decrease of the thickness of the lipid bilayer (dL) of PSUR upon PxB binding is negligible. The hydrophobic tail of the PxB molecule does not penetrate the bilayer as derived from SANS data analysis and changes in lateral pressure monitored by excimer fluorescence at two depths of the hydrophobic region of the bilayer. Changes in dL of protein-free MS show a biphasic dependence on the adsorbed amount of PxB with a minimum close to the point of electroneutrality of the mixture. Our results do not discourage the concept of a combined treatment with PxB-enriched Curosurf. However, the amount of PxB must be carefully assessed (less than 5 wt % relative to the mass of the surfactant) to avoid inversion of the surface charge of the membrane.

Thermodynamic and Structural Study of Budesonide-Exogenous Lung Surfactant System.

The clinical benefits of using exogenous pulmonary surfactant (EPS) as a carrier of budesonide (BUD), a non-halogenated corticosteroid with a broad anti-inflammatory effect, have been established. Using various experimental techniques (differential scanning calorimetry DSC, small- and wide- angle X-ray scattering SAXS/WAXS, small- angle neutron scattering SANS, fluorescence spectroscopy, dynamic light scattering DLS, and zeta potential), we investigated the effect of BUD on the thermodynamics and structure of the clinically used EPS, Curosurf®. We show that BUD facilitates the Curosurf® phase transition from the gel to the fluid state, resulting in a decrease in the temperature of the main phase transition (Tm) and enthalpy (ΔH). The morphology of the Curosurf® dispersion is maintained for BUD < 10 wt% of the Curosurf® mass; BUD slightly increases the repeat distance d of the fluid lamellar phase in multilamellar vesicles (MLVs) resulting from the thickening of the lipid bilayer. The bilayer thickening (~0.23 nm) was derived from SANS data. The presence of ~2 mmol/L of Ca2+ maintains the effect and structure of the MLVs. The changes in the lateral pressure of the Curosurf® bilayer revealed that the intercalated BUD between the acyl chains of the surfactant's lipid molecules resides deeper in the hydrophobic region when its content exceeds ~6 wt%. Our studies support the concept of a combined therapy utilising budesonide-enriched Curosurf®.

Loss of 15-Lipoxygenase in Retinodegenerative RCS Rats.

Retinitis pigmentosa (RP) is a retinal degenerative disease associated with a diversity of genetic mutations. In a natural progression study (NPS) evaluating the molecular changes in Royal College of Surgeons (RCS) rats using lipidomic profiling, RNA sequencing, and gene expression analyses, changes associated with retinal degeneration from p21 to p60 were evaluated, where reductions in retinal ALOX15 expression corresponded with disease progression. This important enzyme catalyzes the formation of specialized pro-resolving mediators (SPMs) such as lipoxins (LXs), resolvins (RvDs), and docosapentaenoic acid resolvins (DPA RvDs), where reduced ALOX15 corresponded with reduced SPMs. Retinal DPA RvD2 levels were found to correlate with retinal structural and functional decline. Retinal RNA sequencing comparing p21 with p60 showed an upregulation of microglial inflammatory pathways accompanied by impaired damage-associated molecular pattern (DAMP) clearance pathways. This analysis suggests that ALXR/FPR2 activation can ameliorate disease progression, which was supported by treatment with an LXA4 analog, NAP1051, which was able to promote the upregulation of ALOX12 and ALOX15. This study showed that retinal inflammation from activated microglia and dysregulation of lipid metabolism were central to the pathogenesis of retinal degeneration in RP, where ALXR/FPR2 activation was able to preserve retinal structure and function.

Oseltamivir phosphate interaction with model membranes.

Oseltamivir belongs to the neuraminidase inhibitors, developed against the influenza virus, and registered under the trademark Tamiflu. Despite its long-term acquaintance, there is limited information in the literature about its physicochemical and structural properties in a lipid-water system. We present an experimentally determined partition coefficient with structural information on the interaction of oseltamivir with the model membrane, its possible location, and its effect on the membrane thermodynamics. The hydrophobic part of the lipid bilayer is affected to a moderate extent, which was proved by slight changes in thermal and structural properties. Hereby, interaction of oseltamivir with the phospholipid bilayer induces concentration dependent decrease of lateral pressure in the bilayer acyl chain region. Oseltamivir charges the bilayer surface positively, which results in the zeta potential increase and changes in anisotropic properties studied by the polarised light microscopy. At the highest oseltamivir concentrations studied, the multilamellar structure is extensively disturbed, likely due to electrostatic repulsion between the adjacent bilayers.

Antibiotic prophylaxis compliance differences in surgery and gynecology/obstetrics services in Huánuco, Peru.

Introduction: Surgical site infections (SSIs) can increase mortality and morbidity in patients after surgery. Antibiotic prophylaxis is an effective measure to prevent SSIs, but inappropriate prescription is frequent. The objective of the study was to determine compliance with the clinical practice guideline for antibiotic prophylaxis in the general surgery and gynecology and obstetrics wards in the city of Huánuco, Peru. Methods: An analytical cross-sectional study was carried out on all surgical interventions in the general surgery and gynecology and obstetrics services during the year 2019. Compliance was determined based on the chosen antibiotic, dose, time of administration, and duration of prophylaxis. Related factors considered were age, presence of co-morbidities, surgery performed, duration of surgery, types of procedure, anesthesia, as well as years as a surgeon and anesthesiologist. Results: A total of 557 medical records of patients with a median age of 33 years undergoing surgery were collected,. Antibiotic prophylaxis was correctly followed in all aspects in 14.6% of cases in the general surgery service and only in 5.6% of cases in the gynecology and obstetrics service. The correct duration of prophylaxis was 11.6% and 19.7% in general surgery and gynecology and obstetrics, respectively. Conclusion: Low compliance with institutional clinical practice guidelines for antibiotic prophylaxis was identified in both services. However, surgical interventions in the general surgery service presented better compliance with antibiotic prophylaxis compared to gynecology and obstetrics procedures.

Efecto cicatrizante en incisiones periodontales por extracto hidroalcohólico de Morinda citrifolia

Los tratamientos periodontales implican cortes y sangrado de la mucosa gingival; la Morinda citrifolia, específicamente sobre los fragmentos encargados de la cicatrización (plaquetas), tiene un efecto más significativo en los procesos curativos de las lesiones. Objetivo. Identificar el potencial cicatrizante de los extractos hidroalcohólicos de Morinda citrifolia (noni peruano) en los procesos regenerativos de las incisiones periodontales al 70% a diversas concentraciones (1%; 5; y 10%) y su efecto coadyuvante acelerador en la vía oral como curación de tejidos. Materiales y Métodos. Se realizó una investigación aplicada, bajo el diseño experimental. Para ello, se llevó a cabo un estudio previo para el análisis farmacognóstico, porcentaje de humedad, pruebas de solubilidad y el análisis fitoquímico cualitativo para garantizar que el análisis farmacológico y la prueba experimental se completaran adecuadamente. Se administraron dosis a cinco ratas albinas macho Holtzman divididas en cuatro grupos a los cuales se les aplicó las concentraciones en cantidades de 0,5 ml dos veces al día en la incisión, la cual se evaluó durante siete días para obtener parámetros específicos, como infección, tono de piel gingival, cierre de heridas, reducción del tamaño de la incisión y porcentaje de curación. Resultados. Indicaron que todos los grupos que se le suministró el extracto hidroalcohólico al 70% en varias concentraciones mejoró su actividad curativa al reducir el tamaño de la incisión en la encía al séptimo día, donde resultó que la mejor concentración fue del 5% en comparación con las otras concentraciones (1% y 10%). Investigación que indica la eficacia de la Morinda citrifolia peruana como acelerador del proceso de curación en la terapia periodontal.

Periodontal treatments involve cuts and bleeding of the gingival mucosa; Morinda citrifolia, specifically on the fragments in charge of healing (platelets), has a more significant effect on the healing processes of the lesions. Objective. To identify the healing potential of hydroalcoholic extracts of Morinda citrifolia (Peruvian noni) in the regenerative processes of periodontal incisions at 70% at various concentrations (1%; 5; and 10%) and its accelerating coadjuvant effect in the oral route as tissue healing. Materials and Methods. An applied research was carried out under an experimental design. For this purpose, a previous study was carried out for pharmacognostic analysis, moisture percentage, solubility tests and qualitative phytochemical analysis to ensure that the pharmacological analysis and experimental test were properly completed. Doses were administered to five male Holtzman albino rats divided into four groups to which the concentrations were applied in 0.5 ml amounts twice daily to the incision, which was evaluated for seven days for specific parameters, such as infection, gingival skin tone, wound closure, incision size reduction and percentage healing. Results. They indicated that all groups that were given the 70% hydroalcoholic extract in various concentrations improved their healing activity by reducing the size of the gingival incision on the seventh day, where it turned out that the best concentration was 5% compared to the other concentrations (1% and 10%). Conclusion. Research indicating the efficacy of Peruvian Morinda citrifolia as an accelerator of the healing process in periodontal therapy.

Os tratamentos periodontais envolvem corte e sangramento da mucosa gengival; a Morinda citrifolia, especificamente sobre os fragmentos responsáveis pela cicatrização (plaquetas), tem um efeito mais significativo nos processos de cicatrização das lesões. Objetivo. Identificar o potencial cicatrizante de extratos hidroalcoólicos de Morinda citrifolia (noni peruano) nos processos regenerativos de incisões periodontais a 70% em diversas concentrações (1%; 5; e 10%) e seu efeito coadjuvante acelerador na via oral como cicatrizante tecidual. Materiais e métodos. Foi realizada uma pesquisa aplicada sob um desenho experimental. Para esse fim, foi realizado um pré-estudo para análise farmacognóstica, porcentagem de umidade, testes de solubilidade e análise fitoquímica qualitativa para garantir que a análise farmacológica e o teste experimental fossem adequadamente concluídos. Cinco ratos albinos Holtzman machos divididos em quatro grupos foram dosados e as concentrações foram aplicadas em quantidades de 0,5 ml duas vezes ao dia na incisão, que foi avaliada por sete dias quanto a parâmetros específicos, como infecção, tônus gengivais da pele, fechamento da ferida, redução do tamanho da incisão e porcentagem de cicatrização. Resultados. Eles indicaram que todos os grupos que receberam extrato hidroalcoólico a 70% em várias concentrações melhoraram sua atividade de cicatrização ao reduzir o tamanho da incisão gengival no sétimo dia, sendo que a melhor concentração foi de 5% em comparação com as outras concentrações (1% e 10%). Conclusão. A pesquisa indica a eficácia da Morinda citrifolia peruana como um acelerador do processo de cicatrização na terapia periodontal.

Epidemiological Profile of Patients with Vulvovaginal Candidiasis from a Sexually Transmitted Infection Clinic in Southern Spain.

Epidemiological data on women suffering from vulvovaginal candidiasis and its recurrence are outdated and vague. The aim of this study was to identify the prevalence of women diagnosed with vulvovaginal candidiasis, as well as the epidemiological profile and associated risk factors in the province of Granada (Spain). Data from the Centre for Sexually Transmitted Infections of the Granada province between 2000 and 2018 (N = 438) were used in this study. Associations between sociodemographic and sexual behaviour variables with vulvovaginal candidiasis were analysed using the Chi-square test and bivariate logistic regression. The prevalence of candidiasis was 14.6%. The sociodemographic profile corresponded to a woman aged 25.14 ± 4.8 years on average, who is of Spanish nationality (60.9%), a student (55.7%), in non-active employment (59.7%), with a higher education (56.7%), single (93.5%), and under 30 years of age (79.7%). Variables associated with this diagnosis were the absence of oro-genital contact (OR = 1.99; 95% CI = 0.25-0.74), having a regular partner (OR = 1.99; 95% CI = 1.05-3.75), and age of sexual debut, with the probability increasing by 12% (95% CI = 1.00-1.24) with each year. In this context, vulvovaginal candidiasis infection is common, and its epidemiological profile is contradictory, so our results do not suggest a relevant role of sexual risk behaviours in the diagnosis. Further research is needed to improve the estimates and factors associated with this infection.

Does environment quality affect the health care spending? Nexus among CO2 emissions, non-renewable energy production, financial development, and health care spending.

This study investigates the dynamic associations among carbon dioxide (CO2) emissions, non-renewable energy production from petroleum derivatives, financial development, and healthcare expenditures to improve environmental quality. This research has employed the balanced annual panel of thirty (30) Organizations for Economic Co-operation and Development (OECD) countries' data set and applied panel vector autoregression (VAR) method depending on the generalized method of moments (GMM). Furthermore, the empirical findings reveal that health spending and CO2 emissions have a favorable bidirectional link, but there is no indication that health spending promotes power generation. The results demonstrate that increased energy consumption and productions affect pollution, and higher CO2 emissions increase healthcare costs. Whereas, energy consumption, financial development, and healthcare expenditures have a positive toward environmental quality.

Hamstring muscle architecture and myotonometer measurements in elite professional football players with a prior strained hamstring.

The purpose of this study was to compare the fascicle length, angle pennation and mechanical properties of the biceps femoris long head (BFlh) in dominant and non-dominant limbs in previously injured and uninjured professional football players. Fifteen professional football players were recruited to participate in this study. Seven players had suffered a BFlh injury during the previous season. Myotonometry mechanical properties were measured in the proximal, common tendon and distal BFlh using MyotonPRO, and angle pennation and fascicle length were also measured. We observed significantly higher distal BFlh frequency, stiffness, decrement, relaxation and creep than in the common tendon and proximal BFlh. The previously injured players showed significantly higher frequency and stiffness, and lower relaxation and creep in the dominant BFlh than did uninjured players. There were no significant differences between the fascicle length and angle pennation in previously injured and uninjured BFlh. Myotonometric measurement provides a quick and inexpensive way to check the properties of the BFlh in professional football players. Professional football players with previous BFlh injury showed higher intrinsic tension and a poorer capacity to deform than did players with no injury to the BFlh.

Chemical modulation of microtubule structure through the laulimalide/peloruside site.

Taxanes are microtubule-stabilizing agents used in the treatment of many solid tumors, but they often involve side effects affecting the peripheral nervous system. It has been proposed that this could be related to structural modifications on the filament upon drug binding. Alternatively, laulimalide and peloruside bind to a different site also inducing stabilization, but they have not been exploited in clinics. Here, we use a combination of the parental natural compounds and derived analogs to unravel the stabilization mechanism through this site. These drugs settle lateral interactions without engaging the M loop, which is part of the key and lock involved in the inter-protofilament contacts. Importantly, these drugs can modulate the angle between protofilaments, producing microtubules of different diameters. Among the compounds studied, we have found some showing low cytotoxicity and able to induce stabilization without compromising microtubule native structure. This opens the window of new applications for microtubule-stabilizing agents beyond cancer treatment.

Modulatory role of prolactin in type 1 diabetes.

OBJECTIVES: Patients with type 1 diabetes mellitus have been reported to have elevated prolactin levels and a possible relationship between prolactin levels and the development of the disease has been proposed. However, some studies show that prolactin mediates beneficial functions in beta cells. Therefore, we review information on the roles of prolactin in type 1 diabetes mellitus. CONTENT: Here we summarize the functions of prolactin in the immune system and in pancreatic beta cells, in addition, we describe studies related to PRL levels, its regulation and alterations of secretion in patients with type 1 diabetes mellitus. SUMMARY: Studies in murine models have shown that prolactin protects beta cells from apoptosis, stimulates their proliferation and promotes pancreatic islet revascularization. In addition, some studies in patients with type 1 diabetes mellitus have shown that elevated prolactin levels correlate with better disease control. OUTLOOK: Prolactin treatment appears to be a promising strategy to improve beta-cell vascularization and proliferation in transplantation and immunotherapies.

Muscle Architecture, Morphology, and Mechanical and Functional Properties of Biceps Femoris Long Head in Professional Soccer Players with a Prior Healed Injured Hamstring.

OBJECTIVE: The aim of the present study was to compare the fascicle length, pennation angle, muscle thickness and stiffness of the biceps femoris long head, and eccentric hamstring strength between injured dominant limbs, injured non-dominant limbs, uninjured dominant limbs and uninjured non-dominant legs in previously injured players, and between dominant and non-dominant legs in uninjured elite soccer players. MATERIALS AND METHODS: Twenty elite soccer players participated in this study. Ultrasound imaging and MyotonPRO were used to determine the morphological and mechanical properties of the biceps femoris long head. Isokinetic and Nordic hamstring exercises were used to assess eccentric hamstring strength. RESULTS: Previously injured players showed substantially lower fascicle length and muscle thickness, and significantly higher biceps femoris long head stiffness than uninjured players, without differences between limbs. CONCLUSION: The morphological and mechanical properties of elite soccer players with hamstring injury history were different from those in uninjured players. The lack of differences between limbs showed that these values are characteristics of individual players that must be considered in the design of programs to prevent BFlh injury.

Diversidad y ecología de Tephritoidea (Insecta: Diptera) en el norte de la Orinoquía colombiana / Diversity and ecology of Tephritoidea (Insecta: Diptera) on the north of the Colombian Orinoquía

Resumen Introducción: Los Tephritoidea, como grupo, tienen un impacto ecológico porque se alimentan de hongos, insectos, flores, frutas en descomposición, excrementos, sudor, nódulos de raíces, carroña (incluidos cadáveres humanos) y otros materiales en descomposición. Las moscas de la fruta son insectos de gran importancia en la agricultura y la investigación genética. En Colombia existen 58 géneros y 224 especies, pero no existe un estudio general del grupo en la Orinoquía colombiana. Objetivo: Caracterizar las comunidades de Tephritoidea (aspectos taxonómicos y ecológicos) y aportar información básica de las especies de importancia económica en la Orinoquía colombiana. Métodos: Semanalmente desde agosto 2017 hasta febrero 2018 recolectamos moscas de la fruta en trampas McPhail cebadas con proteína de maíz, en un huerto doméstico y un fragmento de bosque en Arauca, y también en Saravena, Orinoquía, Colombia. Resultados: Identificamos 27 especies (12 Tephritidae, 11 Richardiidae y 4 Lonchaeidae), nueve de ellas plagas agrícolas. Euarestopsis paupera, Hemixantha lutea, Melanoloma affinis, Melanoloma cyanogaster, Melanoloma varians y Sepsisoma anale se reportan por primera vez para Colombia. Se calcularon los índices de diversidad para las comunidades estudiadas, encontrando diferencias entre las localidades y ambiente. Se discute la influencia de las condiciones ambientales sobre la variabilidad encontrada. Se encontraron nueve especies de moscas consideradas como plagas de producciones agrícolas y para estas especies se estudió su relación con plantas hospederas y la dinámica poblacional. Conclusiones: Seis meses de muestreo produjeron varios primeros registros, lo que sugiere que la fauna de Tephritoidea está submuestreada en la región. La temporada de lluvias y las actividades humanas se correlacionan con la diversidad y abundancia de especies en la Orinoquía colombiana.

Abstract Introduction: The Tephritoidea as a group, have an ecological impact because they feed on fungi, insects, flowers, decaying fruit, excrement, sweat, root nodules, carrion (including human corpses), and other decomposing materials. The fruit-flies are insects of great importance in agriculture and genetic research. In Colombia, there are 58 genera and 224 species, but there is no general study of the group in the savannas of Orinoquía. Objective: To characterize the Tephritoidea communities (taxonomic and ecological aspects) and to provide basic information about the economically important species in the Colombian Orinoquía. Methods: Weekly from August 2017 to February 2018 we collected flies from fruits and McPhail traps baited with corn protein, in a domestic orchard and a forest fragment in Arauca, and also in Saravena, Orinoquía, Colombia. Results: We identified 27 species (12 Tephritidae, 11 Richardiidae and 4 Lonchaeidae), nine of them agricultural pests. Euarestopsis paupera, Hemixantha lutea, Melanoloma affinis, Melanoloma cyanogaster, Melanoloma varians and Sepsisoma anale are reported for the first time from Colombia. A diversity index was calculated for studied communities, being differences between localities and sites. Influence of climatic conditions over variability was found and is discussed. Nine species of fruit flies, which are considered agricultural pests, were identified. For these species their relationship with host plants and population dynamics were studied. Conclusions: Six months of sampling produced several first reports, suggesting that the fauna of Tephritoidea is undersampled in the region. The rainy season, and human activities, correlate with species diversity and abundance in the Colombian Orinoquía.

Evaluating the Injection Moulding of Plastic Parts Using In Situ Time-Resolved Small-Angle X-ray Scattering Techniques.

In this study, we describe the design and fabrication of an industrial injection moulding system that can be mounted and used on the NCD-SWEET small-angle X-ray scattering beamline at ALBA. We show how highly useful time-resolved data can be obtained using this system. We are able to evaluate the fraction of the material in the mould cavity and identify the first material to solidify and how this varies with the injection temperature. The design follows current industrial practice and provides opportunities to collect time-resolved data at several points within the mould cavity so that we can build up a 4D perspective of the morphology and its temporal development. The quantitative data obtained will prove invaluable for the optimisation of the next generation of injection moulding techniques. This preliminary work used results from the injection moulding of a general-purpose isotactic polypropylene.

Association between Galectin Levels and Neurodegenerative Diseases: Systematic Review and Meta-Analysis.

Galectins are a family of proteins with an affinity for ß-galactosides that have roles in neuroprotection and neuroinflammation. Several studies indicate that patients with neurodegenerative diseases have alterations in the concentration of galectins in their blood and brain. However, the results of the studies are contradictory; hence, a meta-analysis is performed to clarify whether patients with neurodegenerative diseases have elevated galectin levels compared to healthy individuals. Related publications are obtained from the databases: PubMed, Central-Conchrane, Web of Science database, OVID-EMBASE, Scope, and EBSCO host until February 2022. A pooled standard mean difference (SMD) with a 95% confidence interval (CI) is calculated by fixed-effect or random-effect model analysis. In total, 17 articles are included in the meta-analysis with a total of 905 patients. Patients with neurodegenerative diseases present a higher level of galectin expression compared to healthy individuals (MDS = 0.70, 95% CI 0.28-1.13, p = 0.001). In the subgroup analysis by galectin type, a higher galectin-3 expression is observed in patients with neurodegenerative diseases. Patients with Alzheimer's disease (AD), amyotrophic lateral sclerosis (ALD), and Parkinson's disease (PD) expressed higher levels of galectin-3. Patients with multiple sclerosis (MS) have higher levels of galectin-9. In conclusion, our meta-analysis shows that patients with neurovegetative diseases have higher galectin levels compared to healthy individuals. Galectin levels are associated with the type of disease, sample, detection technique, and region of origin of the patients.

Towards automatic waste containers management in cities via computer vision: containers localization and geo-positioning in city maps.

This paper describes the scientific achievements of a collaboration between a research group and the waste management division of a company. While these results might be the basis for several practical or commercial developments, we here focus on a novel scientific contribution: a methodology to automatically generate geo-located waste container maps. It is based on the use of Computer Vision algorithms to detect waste containers and identify their geographic location and dimensions. Algorithms analyze a video sequence and provide an automatic discrimination between images with and without containers. More precisely, two state-of-the-art object detectors based on deep learning techniques have been selected for testing, according to their performance and to their adaptability to an on-board real-time environment: EfficientDet and YOLOv5. Experimental results indicate that the proposed visual model for waste container detection is able to effectively operate with consistent performance disregarding the container type (organic waste, plastic, glass and paper recycling,…) and the city layout, which has been assessed by evaluating it on eleven different Spanish cities that vary in terms of size, climate, urban layout and containers' appearance.

Decarbonisation of calcium carbonate in sodium hydroxide solutions under ambient conditions: effect of residence time and mixing rates.

The decarbonisation of CaCO3 is essential for the production of lime (Ca(OH)2 and CaO), which is a commodity required in several large industries and the main precursor for cement production. CaCO3 is usually decarbonised at high temperatures, generating gaseous CO2 which will require post-process capture to minimise its release into the environment. We have developed a new process that can decarbonise CaCO3 under ambient conditions, while sequestering the CO2 as Na2CO3·H2O or Na2CO3 in the same stage. Here, the effects of increasing stirring rates and residence times on reaction efficiency of the key reaction occurring between CaCO3 and NaOH solution are studied. It is shown that the reaction is enhanced at lower stirring rates and longer residence times up to 300 seconds of contact between the reactants. The mass balance performed for Ca and CO2 revealed that up to the 95% of the process CO2 embodied in CaCO3 was sequestered, with maximum capture rate assessed at nn moles CO2 captured per second of reaction progress. A deeper insight into the precipitation of Na2CO3·H2O or Na2CO3 under different reaction conditions was gained, and SEM-EDX analysis enabled the observation of the reaction front by detection of Na migrating towards inner regions of partially-reacted limestone chalk particles.

Changing the Paradigm-Controlling Polymer Morphology during 3D Printing Defines Properties.

Direct digital manufacturing consists of a set of techniques that enable products to be fabricated directly from their digital definition, without the use of complex tooling or moulds. This manufacturing approach streamlines prototyping and small-scale production, as well as the mass customization of parts with complex designs immediately fixed before fabrication. With broad applicability, there are clearly opportunities in the field of medical devices for its use. However, many of the developments of direct digital manufacturing focus on simply specifying the shape or the form of the product, and this limited scope throws away many of the particular advantages of direct digital manufacturing. This work is focused on remedying this situation so that the digital specification of the fabricated product includes the properties as well as the form of the product. We use in situ time-resolving small-angle X-ray scattering measurements performed at the ALBA Synchrotron Light Source in Barcelona to evaluate the control that can be exerted on the morphology of a semi-crystalline polymer during extruder-based 3D printing. We use this as a methodology for printing the patterns of the morphology of the polymer to realise the patterns of properties of the polymeric material, specifically the modulus of the polymer. We give an example of products produced in this manner that contain spatial variation in their properties.