Rugulopteryx okamurae: Effect of hydrothermal acid pretreatment on the saccharification process.

The biological invasion caused by the invasive macroalga Rugulopteryx okamurae is causing increasing concern in southern Europe. To reduce its impact, this brown alga can be treated from a biorefinery approach. In this study, the macroalga is used as raw material to obtain fermentable sugars, which can be converted into high value-added products. The alga was exposed to hydrothermal and hydrothermal acid pretreatment and the pretreated biomass was used for enzymatic hydrolysis, achieving a hydrolysate with a reducing sugar concentration of almost 25 g/L (49.2% more than with non-pretreated alga). In addition, the combined severity factor was calculated to identify the best pretreatment conditions, finding the optimum in those pretreatments performed with 0.2 N HCl concentration and 15 min reaction time. Based on the results, it would be interesting to carry out new studies using the saccharified medium obtained under optimal conditions to obtain value-added compounds by fermentation.

A Novel Hospital Medicine Training Track for Internal Medicine Residents: Description and Program Evaluation of the First 15 Years.

Background: The growth of hospital medicine has resulted in a parallel growth of hospital medicine training within internal medicine residency programs (IMRPs), but the experience and outcomes of these training offerings have not yet been described. Objective: To describe the first dedicated hospitalist track and the program evaluation data. Methods: The University of Colorado Hospitalist Training Track (HTT) is a 3-year track within the IMRP with robust inpatient clinical training, specialized didactics, experiential improvement work, and career mentorship. We collected data on graduates' current practices and board certification pass rates. To further evaluate the track, we electronically sent a cross-sectional survey to 124 graduates from 2005 to 2019 to identify current practice settings, graduate roles, and assessment of the training track. Results: Among 124 graduates, 97 (78.2%) practice hospital medicine, and the board certification pass rate was slightly higher than the overall IMRP pass rate for those graduating classes. Sixty-two (50%) graduates responded to the survey. Among respondents, 50 (80.6%) currently practice hospital medicine and 34 (54.8%) practice in an academic setting. The majority (50, 80.6%) hold leadership roles and are involved in a variety of scholarship, educational, and operational projects. Dedicated clinical training, didactics, and mentorship were valued by respondents. Conclusions: This represents the first description and program evaluation of a HTT for IM residents. A dedicated HTT produces graduates who choose hospital medicine careers at high rates and participate in a wide variety of leadership and nonclinical roles.

Simultaneous production of carotenoids and chemical building blocks precursors from chlorophyta microalgae.

Replacement of fossil fuels has to be accompanied by the incorporation of bio-based procedures for the production of fine chemicals. With this aim, the microalga Chlamydomonas reinhardtii was selected for its ability to accumulate starch, an environmentally-friendly alternative source of chemical building blocks, such as 5'-hydroxymethylfurfural or levulinic acid. The content of appreciated lipophilic coproducts was assessed in the selected microalga cultured at different nutritional conditions; and the parameters for the acidic hydrolysis of the algal biomass, obtained after pigments extraction, were optimized using a Central Composite Design. Response Surface Methodology predicted that the optimal hydrolysis conditions were elevated temperature, high DMSO % and short hydrolysis time for glucose. LA was favored at long times and high acid % and 5'-HMF at lower acid % and high DMSO %. Chlamydomonas can therefore be used as a sustainable feedstock for the simultaneous production of high-added value lipophilic compounds and platform chemicals.

Tagasaste, leucaena and paulownia: three industrial crops for energy and hemicelluloses production.

BACKGROUND: Burning fast-growing trees for energy production can be an effective alternative to coal combustion. Thus, lignocellulosic material, which can be used to obtain chemicals with a high added value, is highly abundant, easily renewed and usually inexpensive. In this work, hemicellulose extraction by acid hydrolysis of plant biomass from three different crops (Chamaecytisus proliferus, Leucaena diversifolia and Paulownia trihybrid) was modelled and the resulting solid residues were used for energy production. RESULTS: The influence of the nature of the lignocellulosic raw material and the operating conditions used to extract the hemicellulose fraction on the heat capacity and activation energy of the subsequent combustion process was examined. The heat power and the activation energy of the combustion process were found to depend markedly on the hemicellulose content of the raw material. Thus, a low content in hemicelluloses resulted in a lower increased energy yield after acid hydrolysis stage. The process was also influenced by the operating conditions of the acid hydrolysis treatment, which increased the gross calorific value (GCV) of the solid residue by 0.6-9.7% relative to the starting material. In addition, the activation energy of combustion of the acid hydrolysis residues from Chamaecytisus proliferus (Tagasaste) and Paulownia trihybrid (Paulownia) was considerably lower than that for the starting materials, the difference increasing with increasing degree of conversion as well as with increasing temperature and acid concentration in the acid hydrolysis. The activation energy of combustion of the solid residues from acid hydrolysis of tagasaste and paulownia decreased markedly with increasing degree of conversion, and also with increasing temperature and acid concentration in the acid hydrolysis treatment. No similar trend was observed in Leucaena diversifolia (Leucaena) owing to its low content in hemicelluloses. CONCLUSIONS: Acid hydrolysis of tagasaste, leucaena and paulownia provided a valorizable liquor containing a large amount of hemicelluloses and a solid residue with an increased heat power amenable to efficient valorization by combustion. There are many potential applications of the hemicelluloses-rich and lignin-rich fraction, for example as multi-components of bio-based feedstocks for 3D printing, for energy and other value-added chemicals.

MSW Compost Valorization by Pyrolysis: Influence of Composting Process Parameters.

The valorization of urban solid waste compost (MSW) in two different composting conditions (different aeration and humidity) has been studied (we work with the hypothesis that the composting process can have a significant influence on a subsequent pyrolysis process). The influence of composting on subsequent pyrolysis of the material was assessed by examining the kinetics of the process, maximizing hydrogen production and minimizing the activation energy. The thermogravimetric analysis carried out on the samples have shown that they have a greater loss of weight of 9-14% at 270-275 °C and 22-27% at 444-446 °C. Using the Kissinger-Akahira-Sunose method, the activation energy values are found to be in the range of 57.78-581.69 kJ mol-1, and the assumption that pyrolysis of compost could be modeled by a first-order reaction may be a suitable approximation. The analysis of the gases produced from the pyrolysis process revealed that hydrogen increases in concentration as composting time advances until intermediate time. In this form, the composting process could be a suitable previous treatment for improving the pyrolysis process. In fact, decreasing aeration and moisture in the MSW composting process led to the production of an increased amount of hydrogen (8.3%) by pyrolysis of the resulting compost and also to a decreased activation energy (102.8 kJ mol-1). These effects were also observed before the end of the composting process in the form of maximum hydrogen production and minimum activation energy after 20 days.

Novel energy crops for Mediterranean contaminated lands: Valorization of Dittrichia viscosa and Silybum marianum biomass by pyrolysis.

Establishing energy crops could be a cost-efficient alternative towards the valorization of the plant biomass produced in contaminated lands, where they would not compete with food production for land use. Dittrichia viscosa and Silybum marianum are two native Mediterranean species recently identified as potential energy crops for degraded lands. Here, we present the first characterization of the decomposition of the biomass of these species during thermo-chemical conversion (pyrolysis). Using a greenhouse study we evaluated whether the quality of D. viscosa and S. marianum biomass for energy production through pyrolysis could be substantially influenced by the presence of high concentrations of soluble trace element concentrations in the growing substrate. For each species, biomass produced in two different soil types (with contrasted trace element concentrations and pH) had similar elemental composition. Behavior during thermal decomposition, activation energies and concentrations of pyrolysis gases were also similar between both types of soils. Average activation energy values were 295 and 300 kJ mol-1 (for a conversion value of α = 0.5) for S. marianum and D. viscosa, respectively. Results suggest that there were no major effects of soil growing conditions on the properties of the biomass as raw material for pyrolysis, and confirm the interest of these species as energy crops for Mediterranean contaminated lands.

The potential of native species as bioenergy crops on trace-element contaminated Mediterranean lands.

The establishment of energy crops could be an option for the management of degraded and contaminated lands, where they would not compete with food production for land use. Here, we aimed to explore the potential of certain native Mediterranean species for the revegetation of contaminated lands for energy production purposes. A field survey was conducted in a trace-element (TE) contaminated area from SW Spain, where the patterns of biomass production, TE accumulation and the calorific value of some thistle species were analyzed along a soil contamination gradient. In a greenhouse experiment the response of two thistle species (Cynara cardunculus and Silybum marianum) and the shrub Dittrichia viscosa to soil contamination was assessed, as well as the effects of these species on some soil microbial parameters involved in nutrient cycling (enzyme activities and arbuscular mycorrhizal colonization in roots). Silybum marianum was able to colonize highly contaminated soils. Its aboveground biomass accumulated Cd and had a relatively high calorific value; this value was similar in biomass obtained from both heavily and moderately contaminated soils. Greenhouse experiment confirmed that S. marianum biomass production and calorific value is scarcely affected by soil contamination. In addition, some soil enzyme activities were clearly enhanced in the S. marianum rhizosphere. Dittrichia viscosa is another promising species, given its capacity to produce a high biomass with appreciable calorific value in acid contaminated soils. Germination of both species was hampered in the acid contaminated soil, and therefore soil pH correction would have to be accomplished before establishing these species on extremely acid soils. Further assessment of the risk of transfer of Cd and other TE to the food chain would be needed to confirm the suitability of these species for the revegetation of contaminated lands with energy production purposes.

Do Health Care Delivery System Reforms Improve Value? The Jury Is Still Out.

BACKGROUND: Widespread restructuring of health delivery systems is underway in the United States to reduce costs and improve the quality of health care. OBJECTIVE: To describe studies evaluating the impact of system-level interventions (incentives and delivery structures) on the value of US health care, defined as the balance between quality and cost. RESEARCH DESIGN: We identified articles in PubMed (2003 to July 2014) using keywords identified through an iterative process, with reference and author tracking. We searched tables of contents of relevant journals from August 2014 through 11 August 2015 to update our sample. SUBJECTS: We included prospective or retrospective studies of system-level changes, with a control, reporting both quality and either cost or utilization of resources. MEASURES: Data about study design, study quality, and outcomes was extracted by one reviewer and checked by a second. RESULTS: Thirty reports of 28 interventions were included. Interventions included patient-centered medical home implementations (n=12), pay-for-performance programs (n=10), and mixed interventions (n=6); no other intervention types were identified. Most reports (n=19) described both cost and utilization outcomes. Quality, cost, and utilization outcomes varied widely; many improvements were small and process outcomes predominated. Improved value (improved quality with stable or lower cost/utilization or stable quality with lower cost/utilization) was seen in 23 reports; 1 showed decreased value, and 6 showed unchanged, unclear, or mixed results.Study limitations included variability among specific endpoints reported, inconsistent methodologies, and lack of full adjustment in some observational trials. Lack of standardized MeSH terms was also a challenge in the search. CONCLUSIONS: On balance, the literature suggests that health system reforms can improve value. However, this finding is tempered by the varying outcomes evaluated across studies with little documented improvement in outcome quality measures. Standardized measures of value would facilitate assessment of the impact of interventions across studies and better estimates of the broad impact of system change.

Changes in health status and frequency of attending religious services among medical inpatients with repeat admissions.

Although frequent attendance at religious services is associated with healthier behaviors and improved health outcomes, this relationship is confounded to the extent that attending religious services requires and displays a certain degree of health. This study surveyed patients over multiple hospitalizations at a large urban academic medical center to test the hypothesis that changes in health status would be accompanied by parallel changes in religious attendance but not with self-rated religiosity and spirituality. Study data confirmed the hypothesis, suggesting that cross-sectional associations between religious attendance and good health outcomes reflect, to some degree, the way changes in health status impact one's ability to attend religious services.

Influence of process variables on the properties of laccase biobleached pulps.

A laccase stage can be used as a pre-treatment of a standard chemical bleaching sequence to reduce environmental concerns associated to this process. The importance of each independent variable and its influence on the properties of the bleached pulp have been studied in depth in this work, using an adaptive network-based fuzzy inference system (ANFIS) with four independent variables (laccase, buffer, mediator and oxygen) as input. Eucalyptus globulus kraft pulp was biobleached using a laccase from Pycnoporus sanguineus and a natural mediator (acetosyringone). Later, an alkaline extraction and a hydrogen peroxide treatment were applied. Most biobleaching processes showed a decrease in kappa number and an increase in brightness with no significant impact on the viscosity values, compared with the control. Oxygen was the variable with the smallest influence on the final pulp properties while the laccase and buffer solution showed a significant influence.

Dilute acid pretreatment of rapeseed straw for fermentable sugar generation.

The influence of the main pretreatment variables on fermentable sugar generation from rapeseed straw is studied using an experimental design approach. Low and high levels for pretreatment temperature (140-200 °C), process time (0-20 min) and concentration of sulfuric acid (0.5-2% w/v) were selected according to previous results. Glucose and xylose composition, as well as sugar degradation, were monitored and adjusted to a quadratic model. Non-sugar components of the hydrolysates were also determined. Enzymatic hydrolysis yields were used for assessing pretreatment performance. Optimization based on the mathematical model show that total conversion of cellulose from pretreated solids can be achieved at pretreatment conditions of 200 °C for 27 min and 0.40% free acid concentration. If optimization criteria were based on maximization of hemicellulosic sugars recovery in the hydrolysate along with cellulose preservation in the pretreated solids, milder pretreatment conditions of 144 °C, 6 min and 2% free acid concentration should be used.

Hydrothermal pre-treatment of rapeseed straw.

As a first step for ethanol production from alternative raw materials, rapeseed straw was studied for fermentable sugar production. Liquid hot water was used as a pre-treatment method and the influence of the main pre-treatment variables was assessed. Experimental design and response surface methodology were applied using pre-treatment temperature and process time as factors. The pretreated solids were further submitted to enzymatic hydrolysis and the corresponding yields were used as pre-treatment performance evaluation. Liquid fractions obtained from pre-treatment were also characterized in terms of sugars and no-sugar composition. A mathematical model describing pre-treatment effects is proposed. Results show that enzymatic hydrolysis yields near to 100% based on pretreated materials can be achieved at 210-220 degrees C for 30-50 min, equivalent to near 70% of glucose present in the raw material. According to the mathematical model, a softer pre-treatment at 193 degrees C for 27 min results in 65% of glucose and 39% of xylose available for fermentation.