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Multiple-step nucleation pathways have been observed during mineral formation in both inorganic and biomineral systems. These pathways can involve precursor aqueous species, amorphous intermediates, or metastable phases. Despite the widespread occurrence of these processes, elucidating the precise nucleation steps and the transformation mechanisms between each step remains a challenging task. Using a suite of potentiometric, microscopic, and spectroscopic tools, we studied the nucleation pathway of SrSO4 as a function of the physico-chemical solution parameters. Our observations reveal that below a threshold supersaturation, nucleation is driven by bound species, akin to the prenucleation cluster model, which directly leads to the formation of the stable phase celestine, SrSO4. At higher supersaturations, this situation is altered, with nucleation dominated by the consumption of free ions. Importantly, this change in nucleation mechanism is coupled to the formation of a hemihydrate metastable phase, SrSO4 · 1/2H2O, which eventually transforms into celestine, adhering to Ostwald’s rule of stages. This transformation is a solution-mediated process, also occurring in the presence of a fluid film and is controlled by the physico-chemical parameters of the surrounding environment. It proceeds through the dissolution of the metastable phase and the de novo crystallization of the final phase. Overall, our results reveal that ion association taking place during the prenucleation stage dictates whether the nucleation pathway goes through an intermediate phase or not. This also underlines that although Ostwald’s rule of stages is a common process, it is not a prerequisite for mineral formation—even in systems where it can occur.

espanolObjetivo Valorar la utilidad de la 18F-DOPA PET/TC cerebral en el diagnostico diferencial de lesiones cerebrales con RM no concluyente. Material y metodos Se estudiaron 12 pacientes, con un total de 16 lesiones, sin diagnostico definitivo tras RM cerebral. Se adquirio estudio 18F-DOPA PET/TC cerebral con doble adquisicion a los 20 y 90 minutos. Se realizo valoracion visual y semicuantitativa con calculo del SUVmax de las lesiones y calculo del ratio T/S (tumor/estriado contralateral) y ratio T/N (tumor/parenquima sano contralateral) para cada uno de los tiempos. Resultados Con base en la escala de valoracion visual y utilizando los ratios T/S ≥ 1 y T/N ≥ 1,3 para determinar la positividad de un estudio, los valores de sensibilidad (S), especificidad (E) y valor predictivo positivo (VPP) han sido los siguientes: valoracion visual (S 100%, E 33,3%, VPP 71,4%), ratio T/S (S 90%, E 100%, VPP 100%) y ratio T/N (S 100%, E 16,6%, VPP 66,6%). Ninguna lesion mostro un aumento del SUVmax en la adquisicion tardia. La 18F- DOPA PET/TC modifico el comportamiento terapeutico en el 75% de los pacientes. Conclusion La 18F-DOPA PET/TC es una herramienta util para diferenciar la etiologia de lesiones cerebrales con RM no concluyente. La imagen tardia (dual point) no aporta un valor anadido al diagnostico final. Los estudios con F-DOPA tienen impacto en el manejo del paciente modificando la conducta terapeutica. EnglishAim To evaluate the utility of brain 18F-DOPA PET/CT in the differential diagnosis of brain lesions with inconclusive MRI. Material and methods Twelve patients were studied, with a total of 16 lesions, without definitive diagnosis after brain MRI. A double acquisition PET/CT brain scan was acquired at 20 and 90 minutes. Visual and semiquantitative assessment was performed with SUVmax calculation of the lesions and calculation of the T/S ratio (tumor/contralateral striatum) and T/N ratio (tumor/contralateral healthy parenchyma) for each time. Results Based on the visual assessment scale and using T/S ratio ≥ 1 and T/N ratio ≥ 1.3 to determine malignancy, the values of sensitivity (S), specificity (E) and positive predictive value (PPV) were: visual assessment (S 100%, E 33.3%, VPP 71.4%), T/S ratio (S 90%, E 100%, VPP 100%) and T/N ratio (S 100%, E 16.6%, VPP 66.6%). No lesion showed an increase in SUVmax in late acquisition. 18F-DOPA PET/CT modified treatment in 75% of the patients. Conclusion 18F-DOPA PET/CT is a useful tool in the study of brain lesions with inconclusive MRI. Late imaging (dual-point) has no added value in the final diagnosis. F-DOPA has an impact on patient management modifying therapeutic behavior.

Aim To evaluate the utility of brain 18F-DOPA PET/CT in the differential diagnosis of brain lesions with inconclusive MRI. Material and methods Twelve patients were studied, with a total of 16 lesions, without definitive diagnosis after brain MRI. A double acquisition PET/CT brain scan was acquired at 20 and 90 min. Visual and semiquantitative assessment was performed with SUVmax calculation of the lesions and calculation of the T/S Ratio (tumor/contralateral striatum) and T/N Ratio (contralateral healthy tumor/parenchyma) for each time. Results Based on the visual assessment scale and using T/S ratio ≥1 and T/N ratio ≥1.3 to determine malignancy, the values of sensitivity (S), specificity (E) and positive predictive value (PPV) were: visual assessment (S 100%, E 33.3%, VPP 71.4%), T/S Ratio (S 90%, E 100%, VPP 100%) and T/N Ratio (S 100%, E 16.6%, VPP 66.6 %). No lesion showed an increase in SUVmax in late acquisition. 18F-DOPA PET/CT modified treatment in 75% of the patients. Conclusion 18F-DOPA PET/CT is a useful tool in the study of brain lesions with inconclusive MRI. Late imaging (dual-point) has no added value in the final diagnosis. FDOPA has an impact on patient management modifying therapeutic behavior.

Tooth extraction is a surgical procedure that is performed due to pulp and periapical pathology, periodontal disease, or teeth that are not deemed to be prosthetically or endodontically restorable. Following tooth extraction, bone resorption and vertical or horizontal defects occur. Traditionally, ridge preservation warrants the use of different agents such as autografts, allografts, xenografts, and mineral or ceramic materials. Autogenous dentin grafts are alternative to ridge preservation with osteoconductive, osteoinductive, and non-immunogenic properties to generate bone formation. The aim of the case report was to evaluate and compare clinical and histological outcomes using an autogenous dentin graft versus an allogeneic bone graft (DFDBA) as an alternative for ridge preservation.

From electrochemical potentiodynamic and potentiostatic techniques, the electrodeposition mechanism and kinetics of palladium nanoparticles (PdNPs) onto a glassy carbon electrode (GCE), from Pd(II) ions dissolved in the choline chloride-urea deep eutectic solvent (reline) at 343 K, are reported for the first time. From the analysis of the potentiostatic current density transients, using the model developed by Palomar-Pardavé et al. [

Exergy and energy analyses of two biodiesel production processes that integrate solar energy as the main energy source were developed to determine the process with the higher efficiency from an energy and exergy approach. The biodiesel production processes were simulated in ASPEN PLUS®, and the solar energy supply was studied in TRNSYS®, using EXCEL® simultaneously for the exergetic analysis. The solar thermal energy collection system can supply 81% of the energy required by the alkali process in the Flash separation equipment. For the supercritical process, solar thermal energy can supply 74.5% of the energy in the preheating and separation stages. The energy efficiency of the supercritical process is higher; nevertheless, the exergetic efficiency of the alkaline process is higher than the supercritical one. Solar collection systems contribute from 85% to 93% of the exergy destroyed by the global process for both cases. The alkaline biodiesel production process has the highest advantages when using solar energy as the main source of energy, compared to a process in supercritical conditions that presents greater irreversibilities and requires more infrastructure to collect the solar resource. However, using solar energy as the foremost energy source offers an alternative to fossil fuels, and it provides an environmental benefit concurrently with the use of biodiesel.

The present work deals with the nucleation and growth process of metallic cobalt clusters onto glassy carbon, and the development of an environmentally friendly recycling process for the recovery of cobalt as a value-added product from spent lithium-ion batteries (LiBs), using a deep eutectic solvent, DES, formed by choline chloride and urea, termed reline. It was shown that reline works as leaching medium to extract Co(II) from cathode powders of dismantled spent batteries, thereby obtaining, after doing the electrodeposition process using the same reline as operating bath, a solid Co metal phase onto a glassy carbon electrode. Finally, supplementary relevant characterization of the deposits formed was carried out by means of scanning electron microscopy, energy-dispersive X-ray spectroscopy and X-rays photoelectrons spectroscopy, XPS.

The biomass industrialization valorisation of grains and cereals is considered an opportunity for the countries where agro-industrial activity is one of its main economic activities, rendering new higher-value products with a concomitant solution to waste accumulation issues. To that end, in this work we describe and characterise bioactive compounds generation from rice husk by semisolid fermentation, obtained from 500 g of the material at room temperature and 60% humidity with mixed cultures of Phanerochaete chrysosporium and Gloeophyllum trabeum. The extract was evaluated in different situations: murine mammary tumour cells (4T1), normal cells (NIH 3T3) and in Lactobacillus acidophilus, and Trichoderma harzianum. The results exhibited that the extract inhibited 4T1 cells at concentrations higher than 20μg/mL, but did not inhibit normal cells, and displayed germicide activity after 3 days incubations. We propose that these functionalized compounds have a potential application in industry/agriculture/medicine obtained from rice husk waste.

8 Figuras.- 4 Tablas, Pd and PdM (M = Fe or Co) nanostructured electrocatalysts were synthesized by the impregnation method and supported on carbon black Vulcan XC-72R for the formic acid oxidation reaction, FAOR, in acid medium. Nitrates or chlorides were used as Fe and Co precursors to study the counter ion role on the physicochemical features and electrochemical performance of the electrocatalysts. TEM analysis showed that PdM was deposited on the carbon material with a particle size around 2–3 nm. From XRD, peaks associated with the fcc palladium planes were observed along with evidence of PdM alloy formation, particularly when the nitrate salts were used as metal precursors. Furthermore, XPS analyses indicated that nitrates promote the metal oxide formation to a greater extent than chlorides, mainly for Pd. PdCo electrocatalyst obtained from nitrates exhibited the highest performance for FAOR with a steady state current density of 451 and 313 μA cm−2 at 200 and 400 mV respectively, which is in both cases, 3 times larger than that developed for a commercial Pd/C catalyst., LJM is grateful to CONACYT for the grant awarded for this research, as well as to the UAM-A and the ICB for the support provided. MGMY, MRR, MPP and AEM thank the SNI for the distinction of their membership and the stipend provided. MGMY is indebted to L'oreál-UNESCO-CONACyT-AMC for the grant Women in Science 2016. MJL and SPR gratefully acknowledge financial support given by Spanish MINECO (ENE2014-52158-C2-1-R).

The objective of the present study was to compare, using accelerometry, the gait changes produced after administration of a dose of 0.2 mg/kg of morphine at the walk in healthy horses. Six mature horses were used, and all animals received two different treatments with, at least, two weeks interval in between. Treatments administered consisted of a single dose of 10 ml of saline solution or a total of 0.2 mg/kg of morphine diluted in 10 ml of saline solution. A three-dimensional accelerometric device was used to collect data continuously while horses were walking. The walking test was performed 10 min prior to injection, and then at 5, 10, 15 and 20 min after injection and then every 10 min for 3 h. Eight variables were calculated including stride kinematic, coordination and energetic parameters. Additionally, the force of acceleration and three components of the power were calculated. Significant interaction was only observed for stride length, propulsion power and the propulsive part of the total power with a reduction in values after morphine administration. Compared to baseline values, stride length values were significantly reduced for 80 min and again 110 min after injection of the opioid and at 5, 15, 20, 30 and 40 min in the case of propulsion power values. For the propulsion component of power, these differences were observed for 20 min when compared to baseline values. The administration of 0.2 mg/kg of morphine to conscious healthy horses produces limited effects on the gait pattern of horses and the effects on locomotor activity are minimal at this dose, not being an important concern for the administration of analgesia in a clinical setting.

IntroductionThe shape of the glucose curve during an oral glucose tolerance test (OGTT) reflects β-cell function in populations without diabetes but has not been as well studied in those with diabetes. A monophasic shape has been associated with higher risk of diabetes, while a biphasic pattern has been associated with lower risk. We sought to determine if phenotypic or metabolic characteristics were associated with glucose response curve shape in adults with type 2 diabetes treated with metformin alone.Research design and methodsThis is a cross-sectional analysis of 3108 metformin-treated adults with type 2 diabetes diagnosed ResultsThe monophasic profile was the most common (67.8% monophasic, 5.5% biphasic, 26.7% continuous rise). The monophasic subgroup was younger, more likely male and white, and had higher body mass index (BMI), while the continuous rise subgroup was more likely female and African American/black. HOMA2-S and fasting glucose did not differ among the subgroups. The biphasic subgroup had the highest early, late, and total insulin and C peptide responses (all pConclusionsBased on the large multiethnic GRADE cohort, sex, race, age, and BMI were found to be important determinants of the shape of the glucose response curve. A pattern of a continuously rising glucose at 2 hours reflected reduced β-cell function and may portend increased glycemic failure rates.Trial registration numberNCT01794143.

Annually, millions of tons of foods are generated with the purpose to feed the growing world population. One particular eatable is orange, the production of which in 2018 was 75.54 Mt. One way to valorize the orange residue is to produce bioethanol by fermenting the reducing sugars generated from orange peel. Hence, the objective of the present work was to determine the experimental conditions to obtain the maximum yield of reducing sugars from orange peel using a diluted acid hydrolysis process. A proximate and chemical analysis of the orange peel were conducted. For the hydrolysis, two factorial designs were prepared to measure the glucose and fructose concentration with the 3,5-DNS acid method and UV-Visible spectroscopy. The factors were acid concentration, temperature and hydrolysis time. After the hydrolysis, the orange peel samples were subjected to an elemental SEM-EDS analysis. The results for the orange peel were 73.530% of moisture, 99.261% of volatiles, 0.052% of ash, 0.687% of fixed carbon, 19.801% of lignin, 69.096% of cellulose and 9.015% of hemicellulose. The highest concentration of glucose and fructose were 24.585 and 9.709 g/L, respectively. The results highlight that sugar production is increased by decreasing the acid concentration.

Introduction It has been estimated that between 15% and 18% of patients who start antiretroviral therapy (ART) do not achieve a successful immune recovery despite complete virological suppression. In the literature this phenomenom is known as poor immune recovery or immunovirological discordance (IVD). Zinc has an immunomodulatory role associated with T lymphocytes and its supplementation could enhance immune recovery. Objective To determine if zinc supplementation on IVD patients prevents immune failure after 12 months of supplementation. Secondary objectives were to determine serum zinc levels in HIV patients with and without IVD and the frequency of hypozincemia in discordant patients. Method We reviewed the historical record of patients under care at Arriarán Foundation. Following inclusion criteria were defined: 1) age ≥ 18 years, 2) standard ART (three effective drugs) for at least 18 months, 3) virologically suppressed for 12 months, 3) persistence of CD4 count ≤200 cells/mm3 and/or increase ≤ 80 cells/mm3 after one year of viral undetectability. A control group was assigned paired 1:1 by sex, age (± 2 years) that did achieved an increase of CD4> 350 cells/ mm3. In both groups plasma zinc levels were determined. In a later phase, patients with IVD were randomized to receive zinc (15 mg daily) versus placebo. Patients were followed for 12 months with CD4 count, viral load and zinc levels determinations every 4–6 months. Results A total of 80 patients, 40 patients with IVD criteria and 40 controls were included. 92.5% were men, and age average was 47.5 years. The median baseline CD4 was 189 cells/mm3 (71–258) in the cases vs. 552.5 cells/ mm3 (317–400) in the control group with a median increase at the end of the study of 39 cell/mm3 and 19 cell/mm3 respectively. There was no difference in baseline plasma zinc levels between both groups (81.7 + 18.1 in cases versus 86.2 + 11.0 in controls). In the 40 patients with IVD, the median absolute increase in CD4 after annual zinc supplementation was 31.5 cells/mm3 in the treated group versus 50 cells/mm3 in the placebo group, this difference being statistically not significant (p = 0.382). Conclusions Patients with IVD have plasma zinc levels similar to those who achieve adequate immune recovery. Zinc supplementation in IVD patients showed a statistically non-significant difference in in CD4 levels between cases and controls. The results warrant a comparative study with a larger number of patients.

Wheat is one of the most important crops worldwide. Mexicali, Baja California, is an important wheat producer in Mexico with an average production of 507,543 t. Wheat straw is generated as a residue which could be used for different purposes such as bioenergy, heat and power generation. In this work, an assessment and potential site determination of a biomass power plant operating with wheat straw as fuel was performed. Aspen Plus was used to evaluate a plant capacity of at least 10 MW considering the physicochemical properties and an higher heating value of 14.86 MJ kg−1 of the wheat straw from the region. The combustion produced 39.76 MW, and the overall plant efficiency was 25.52%. The development of the multi-criteria geographic information system model allowed us to assess and analyse four factors and three restrictions to determine the potential site for the biomass power plant. The factors were raw material, wheat crops, electric transmission lines, paths and roads, water canals and aqueducts, while the restrictions were localities, Ramsar sites and faults. The biomass power plant is technically and geographically feasible. The geographical coordinates of the potential site of the biomass power plant that fulfils all the criteria are 32°29′29.72″N and 115°15′39.45″W.

It has been estimated that between 15% and 18% of patients who start antiretroviral therapy (ART) do not achieve a successful immune recovery despite complete virological suppression. In the literature this phenomenom is known as poor immune recovery or immunovirological discordance (IVD). Zinc has an immunomodulatory role associated with T lymphocytes and its supplementation could enhance immune recovery. OBJECTIVE:to determine if zinc supplementation on IVD patients prevents immune failure after 12 months of supplementation. Secondary objectives were to determine serum zinc levels in HIV patients with and without IVD and the frequency of hypozincemia in discordant patients.METHOD: we reviewed the historical record of patients under care at Arriarán Foundation. Following inclusion criteria were defined: 1) age>18 years, 2) standard ART (three effective drugs) for at least 18 months, 3) virologically suppressed for 12 months, 3) persistence of CD4 count 350 cells/ mm3. In both groups plasma zinc levels were determined. In a later phase, patients with IVD were randomized to receive zinc (15 mg daily) versus placebo. Patients were followed for 12 months with CD4 count, viral load and zinc levels determinations every 4-6 months. RESULTS: a total of 80 patients, 40 patients with IVD criteria and 40 controls were included. 92.5% were men, and age average was47.5years. The median baseline CD4 was189cells/mm3(71-258) in the cases vs.552.5cells/ mm3(317-400) in the controlgroup with a total increase at the end of the study of 34 cell/mm3and 30 cell/mm3respectively.There was no difference in baseline plasma zinc levels between both groups (81.7 + 18.1in cases versus86.2 + 11.0in controls).In the 40 patients with IVD, the median absolute increase in CD4 after annual zinc supplementation was31.5cells/mm3in the treated group versus50cells/mm3in the placebo group, this difference being statistically not significant(p = 0.382).CONCLUSIONS: Patients with IVD have plasma zinc levels similar to those who achieve adequate immune recovery.Zinc supplementation in IVD patients showed a statistically non-significant increase in CD4 levelsbetween cases and controls. The results warrant a comparative study with a larger number of patients.

The brewing industry generates, as the primary coproduct, brewers&rsquo, spent grain (BSG). In Mexicali, Baja California, Mexico, there are 17 companies that generated 282 tons of BSG by 2016. Cattle feeding is the most common type of disposal for this waste. However, it can be valorized for the production of bioenergy or as a source of added-value products. Therefore, the objective of the present work was to assess the physicochemical properties of the brewers&rsquo, spent grain from a local craft brewery, to choose the most appropriate exploitation route. Chemical and morphological analyses were carried out by energy dispersive X-ray fluorescence spectroscopy (EDX), scanning electron microscopy, and the higher heating value determination. The results of the proximate analyses were 72.32% moisture, 78.47% volatile matter, 17.48% fixed carbon, and 4.05% ash. The results of the chemical analysis for extractables were 5.23% using organic solvent and 50.25% using hot water. The content determination were 17.13% lignin, 26.80% cellulose, and 37.17% hemicellulose. The results of the ultimate analysis were 43.59% C, 6.18% H, 3.46% N, and 37.22% O. The higher heating value experimentally obtained was 18.70 MJ/kg. Moreover, in the EDX analysis, Ca, P, K, and S were mainly found. It is recommendable to valorize the BSG through the xylitol, bioethanol or biogas production, because of its high moisture, hemicellulose and cellulose content.

To evaluate the utility of brainTwelve patients were studied, with a total of 16 lesions, without definitive diagnosis after brain MRI. A double acquisition PET/CT brain scan was acquired at 20 and 90min. Visual and semiquantitative assessment was performed with SUVmax calculation of the lesions and calculation of the T/S Ratio (tumor/contralateral striatum) and T/N Ratio (contralateral healthy tumor/parenchyma) for each time.Based on the visual assessment scale and using T/S ratio ≥1 and T/N ratio ≥1.3 to determine malignancy, the values of sensitivity (S), specificity (E) and positive predictive value (PPV) were: visual assessment (S 100%, E 33.3%, VPP 71.4%), T/S Ratio (S 90%, E 100%, VPP 100%) and T/N Ratio (S 100%, E 16.6%, VPP 66.6 %). No lesion showed an increase in SUVmax in late acquisition.

Background With the availability of high-quality asthma guidelines worldwide, one possible approach of developing a valid guideline, without re-working the evidence, already analysed by major guidelines, is the ADAPTE approach, as was used for the development of National Guidelines on asthma. Methods The guidelines development group (GDG) covered a broad range of experts from medical specialities, primary care physicians and methodologists. The core group of the GDG searched the literature for asthma guidelines 2005 onward, and analysed the 11 best guidelines with AGREE-II to select three mother guidelines. Key clinical questions were formulated covering each step of the asthma management. Results The selected mother guidelines are British Thoracic Society (BTS), GINA and GEMA 2015. Responses to the questions were formulated according to the evidence in the mother guidelines. Recommendations or suggestions were made for asthma treatment in Mexico by the core group, and adjusted during several rounds of a Delphi process, taking into account: 1. Evidence; 2. Safety; 3. Cost; 4. Patient preference – all these set against the background of the local reality. Here the detailed analysis of the evidence present in BTS/GINA/GEMA sections on prevention and diagnosis in paediatric asthma are presented for three age-groups: children with asthma ≤5 years, 6–11 years and ≥12 years. Conclusions For the prevention and diagnosis sections, applying the AGREE-II method is useful to develop a scientifically-sustained document, adjusted to the local reality per country, as is the Mexican Guideline on Asthma.