Biohydrogen production by lactate-driven dark fermentation of real organic wastes derived from solid waste treatment plants.

This study evaluated the hydrogen production potential through lactate-driven dark fermentation (LD-DF) of organic wastes from solid waste treatment plants, including the organic fraction of municipal solid waste (OFMSW), mixed sewage sludge, and two OFMSW leachates. In initial batch fermentations, only OFMSW supported a significant hydrogen yield (70.1 ± 7.7 NmL-H2/g-VS added) among the tested feedstocks. Lactate acted as an important hydrogen precursor, requiring the presence of carbohydrates for sequential two-step lactate-type fermentation. The impact of operational pH (5.5-6.5) and initial total solids (TS) concentration (5-12.5 % w/w) was also evaluated using OFMSW as substrate, obtaining hydrogen yields ranging from 6.6 to 55.9 NmL-H2/g-VSadded. The highest yield occurred at 6.5 pH and 7.5 % TS. The LD-DF pathway was indicated to be present under diverse pH and TS conditions, supported by employing a specialized microbial consortium capable of performing LD-DF, along with the observed changes in lactate levels during fermentation.

Ectoines production from biogas in pilot bubble column bioreactors and their subsequent extraction via bio-milking.

Despite the potential of biogas from waste/wastewater treatment as a renewable energy source, the presence of pollutants and the rapid decrease in the levelized cost of solar and wind power constrain the use of biogas for energy generation. Biogas conversion into ectoine, one of the most valuable bioproducts (1000 €/kg), constitutes a new strategy to promote a competitive biogas market. The potential for a stand-alone 20 L bubble column bioreactor operating at 6% NaCl and two 10 L interconnected bioreactors (at 0 and 6% NaCl, respectively) for ectoine production from biogas was comparatively assessed. The stand-alone reactor supported the best process performance due to its highest robustness and efficiency for ectoine accumulation (20-52 mgectoine/gVSS) and CH4 degradation (up to 84%). The increase in N availability and internal gas recirculation did not enhance ectoine synthesis. However, a 2-fold increase in the internal gas recirculation resulted in an approximately 1.3-fold increase in CH4 removal efficiency. Finally, the recovery of ectoine through bacterial bio-milking resulted in efficiencies of >70% without any negative impact of methanotrophic cell recycling to the bioreactors on CH4 biodegradation or ectoine synthesis.

Roles of Palmitoleic Acid and Its Positional Isomers, Hypogeic and Sapienic Acids, in Inflammation, Metabolic Diseases and Cancer.

In the last few years, the monounsaturated hexadecenoic fatty acids are being increasingly considered as biomarkers of health with key functions in physiology and pathophysiology. Palmitoleic acid (16:1n-7) and sapienic acid (16:1n-10) are synthesized from palmitic acid by the action of stearoyl-CoA desaturase-1 and fatty acid desaturase 2, respectively. A third positional isomer, hypogeic acid (16:1n-9) is produced from the partial ß-oxidation of oleic acid. In this review, we discuss the current knowledge of the effects of palmitoleic acid and, where available, sapienic acid and hypogeic acid, on metabolic diseases such as diabetes, cardiovascular disease, and nonalcoholic fatty liver disease, and cancer. The results have shown diverse effects among studies in cell lines, animal models and humans. Palmitoleic acid was described as a lipokine able to regulate different metabolic processes such as an increase in insulin sensitivity in muscle, ß cell proliferation, prevention of endoplasmic reticulum stress and lipogenic activity in white adipocytes. Numerous beneficial effects have been attributed to palmitoleic acid, both in mouse models and in cell lines. However, its role in humans is not fully understood, and is sometimes controversial. Regarding sapienic acid and hypogeic acid, studies on their biological effects are still scarce, but accumulating evidence suggests that they also play important roles in metabolic regulation. The multiplicity of effects reported for palmitoleic acid and the compartmentalized manner in which they often occur, may suggest the overlapping actions of multiple isomers being present at the same or neighboring locations.

The evolution of the role of nursing in primary health care using Bourdieu's concept of habitus. A grounded theory study.

AIMS: To analyse the global process by which Spanish nurses have acquired a differentiated role in primary health care and to develop a theory that explains the evolution of this role. DESIGN: Grounded Theory was selected, as proposed by Glaser and Strauss, following the theoretical framework of Bourdieu's habitus. METHODS: Thirteen in-depth interviews were conducted between 2012 and 2015, using theoretical sampling and seeking maximum variability. The analysis of the data included progressive coding and categorization, constant comparative analysis and memo writing. RESULTS: A core category emerged, "Autonomy", composed of three categories: "Between illusion and ignorance. Genesis of a habitus", "The recognisable and recognised habitus" and "Habitus called into question", showing the genesis of the nursing role in primary health care and the elements that influence the autonomy of the role: the ability to decide their training, assume their own leadership, configure teams and acquire independent skills. "Seeking autonomy" was the substantive theory that emerged from the data. CONCLUSION: The results reveal the elements that strengthen the autonomous professional role and that this role is legitimated when two elements are identified: the acquisition of a habitus, based on practices carried out regularly and the recognition of this habitus by the population and others professionals. IMPACT: The results of this study identify the elements that guide and strengthen the professional role and redefine the concept of autonomy. These are operational findings and could potentially be used to define new strategies for advancing the role of nursing in primary health care.

Clinical study comparing the accuracy of interocclusal records, digitally obtained by three different devices.

OBJECTIVE: The aim of the present cross-sectional study was to compare the interocclusal contact records obtained by three different digital methods (intra- and extraoral digital scanners and T-Scan III system) with the conventional method (articulating paper). MATERIALS AND METHODS: Twenty-five healthy volunteers were selected. As a control group, maximum intercuspation occlusal contacts were registered and photographed from the patients with an 8 µm articulating paper. Then, intraoral conventional elastomer impressions were taken and after obtaining the corresponding plaster models of every patient they were scanned with an extraoral scanner (Zfx Evolution, Zimmer Biomet Dental) (group 1). Moreover, digital impressions were made with an intraoral scanner (Trios Color POD, Phibo, 3Shape) and contacts were also registered (group 2). Finally, T-Scan III records were made and stored for further analysis (group 3). Two previously calibrated examiners independently evaluated the interocclusal contacts from every group. Data was analyzed by using Kappa index test and Pearson's chi-square test. Diagnostic tests and ROC curve were also performed. RESULTS: Kappa interoperator index was 70.6% (better agreement). In Kappa intraoperator index, the best value was obtained in the intraoral scanner group (moderate agreement) and the worst with T-Scan III group (low agreement). ROC curve showed highest values in the intraoral scanner group (0.817) and lowest values in the T-Scan III group (0.613). CONCLUSION: Results suggest greater reliability to record occlusal contacts with the intraoral scanner. CLINICAL RELEVANCE: Intraoral scanners seem to be reliable in registering intermaxillary occlusal contacts when compared with the current gold standard.

Original versus nonoriginal cast-to-gold abutment-implant connection: Analysis of the internal fit and long-term fatigue performance.

STATEMENT OF PROBLEM: Restoring implants with nonoriginal abutments is common. However, studies that evaluated compatible abutments with long-term fatigue performance are lacking. PURPOSE: The purpose of this in vitro study was to assess the internal fit and the cyclic fatigue life after artificial aging of 3 implant-abutment configurations restored with 1 original and 2 compatible nonoriginal cast-to-gold abutments. MATERIAL AND METHODS: Forty-eight original internal hexagon connection implants were connected to 3 different brands of abutments (n=16): 1 original to the implant system and the other 2 with nonoriginal abutments. Internal fit and the percentage of surface with tight contact were assessed by scanning electron microscopy in 12 cross-sectioned specimens (n=4) at 3 different areas (platform, internal, and screw). Thirty-six implant-abutment-crown specimens (n=12) were immersed in artificial saliva and thermocycled for 10 000 cycles between 5 °C and 55 °C. Subsequently, a cyclic load test, as per International Organization for Standardization (ISO) Standard 14 801, was completed in a universal testing machine at 2 Hz in air. RESULTS: The original abutments presented the best fit and highest percentage of tight contact in the internal areas. In addition, the original abutments showed the lower cyclic fatigue strength degradation and the highest long-term success. CONCLUSIONS: Occlusal loads are transferred more homogenously through the system when original abutments are used because of the better fit between the internal components, leading to increased fatigue resistance.

The Impact of Health Human Resources Policies in Primary Care Nursing: A Qualitative Study.

BACKGROUND: Organizational culture plays a key role regarding organizational outcomes and determining strategies, goals, and modes of operating which is associated with higher rates of worker morale, turnover and lower adverse events related to patient quality of care issues. AIM: to describe the impact of the relocation of nurses from hospitals and other contexts to primary care from the perspective of primary care nurses. METHODS: A qualitative, focused ethnographic study. Site: Cantabro Health Service, Cantabria, Spain. Purposeful sampling methods were used to include nurses who were working in primary care during the study, and who had previous experience of at least one year in primary care. Observation (385 hours, 7 months) and in-depth interviews (17) were used to collect data. A thematic analysis was applied. RESULTS: Four themes emerged from the data: a) staff policies applied, b) beliefs regarding the newly incorporated nursing staff, c) reasons for relocation to primary care, and d) concern for the future. CONCLUSIONS: In primary care, the relocation of non-qualified nursing professionals who are at the end of their career may have a negative impact on the organizational culture. It is necessary to research the most appropriate measures for guaranteeing a satisfactory work environment based on nurses who are qualified in primary health care settings.

Intraoral versus extraoral digital occlusal records: a pilot study.

The aim of the present pilot study was to analyze the reliability of interocclusal contact records generated with an intraoral scanner (TRIOS Standard) and an extraoral scanner (Zfx Evolution). Ten patients were selected. The number of occlusal contacts was first determined with the conventional method using 8-µm articulating paper (gold standard) (control). These conventional records were then compared with the intra- and extraoral digital records. Diagnostics tests (sensitivity, specificity, predictive values for positives and negatives), receiver operating characteristic (ROC) curve, and Cohen's kappa coefficient were performed to analyze the data. The kappa index of the extraoral scanner (40.7%) was considered to be 'moderate,' and better than that of the intraoral scanner (26.1%), which was considered to be 'low.' The extraoral scanner showed better results in the diagnostic test and in the ROC curve. The first results suggest that the extraoral scanner is more reliable for recording occlusal contacts than the intraoral scanner.

Acheulean without handaxes? Assemblage variability at FLK West (Lowermost Bed II, Olduvai, Tanzania).

The FLK West sequence is divided into six fluvial stratigraphic levels, each of which provided archaeological materials. In the present paper we outline the major similarities and differences displayed by the lithic assemblages in FLK W, particularly the lower assemblages, which have yielded more objects than the upper ones. The differences noted in the absence-presence and frequency of LCTs may be explained in occupational terms, while the similarities in raw material selection, core reduction and flake retouching patterns indicate homogeneous cultural decisions and cognitive skills. We conclude that these assemblages were likely formed by the same hominin group or taxon and, therefore, the assemblage variability registered would correspond to different expressions of the same economic structure.

The origin of the Acheulean. Techno-functional study of the FLK W lithic record (Olduvai, Tanzania).

The Acheulean materials documented in FLK West dated c. 1.7 Ma. are the focus of the present work. An original techno-functional approach is applied here to analyze the origin of Acheulean tools. According to the results, these tools were employed in different functional contexts in which tasks of different durations that transformed resources with different resistances were carried out. The exploitation of large and resistant resources suggests that the economic mechanism governing the manufacture of these tools was an increase in the demand of the work load. The decision processes underlying the production of these tools have thus an evident functional motivation. However, the presence of a refined handaxe in the studied sample indicates that the design form and production principles of handaxe manufacture were the result of an abrupt emergence rather than a long gradual development. The integration of mechanical and ergonomic investigation in our research has been crucial to explain how a core-and-flake industry gave way to a technology based on the production of large and heavy shaped tools.