652 research outputs found

    Screening of environmental yeasts for the fermentative production of arabitol from lactose and glycerol

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    Arabitol is a sugar alcohol, stereoisomer to xylitol, which is enlisted among the main target for biorefineries. It can serve as low calorie sweetener and as building block in the enantiopure synthesis of immunosuppressive glycolipids, herbicides, and drugs. Several studies described the fermentative production of arabitol by osmophilic yeasts, cultured with high concentrations of D-glucose. The utilization of cheaper carbon sources, such as glycerol or lactose, is of great interest for biorefinery implementation, but information on exploitation to arabitol production is still scarce. In the present study 50 yeasts belonging to 24 ascomycetous species were screened for the ability to grow and produce arabitol in presence of 80 g/L lactose or glycerol. Production from lactose was generally unsuccessful, the best producer being Kluyveromyces lactis WC 1401 with 0.94 g/L in 160 h. Production from glycerol was promising, with Zygosaccharomyces rouxii WC 1206, Pichia guilliermondii CBS 566, Hansenula anomala WC 1501, and Candida freyschussii ATCC 18737 yielding 3 to 4.5 g/L arabitol, with conversion yield (YP/S) ranging from 11 to 21.7%. Batch growth with high initial glycerol amount (160 g/L) resulted in higher production, with H. anomala WC 1501 yielding 10.0 g/L arabitol (YP/S = 12%) in 160 h. Preliminary bioreactor fermentations with H. anomala WC 1501 indicated that production is not growth associated and revealed some major parameters affecting production, such as the pH and the C:N ratio, that will be the target of following studies aiming at process optimization. Cultivation under controlled oxygenation (DOT = 20%) and pH (= 3.0) resulted in improvement in the performance of H. anomala WC 1501, yielding 16.1 g/L arabitol. Cultivation in a medium with high C:N ratio, lacking inorganic nitrogen yielded 17.1 g/L arabitol. Therefore, this strain was selected for the development of a fed-batch process, aiming to improve the efficiency of the biomass, generated in the growth phase, and increasing the production in the stationary phase

    Improved fed-batch processes with Wickerhamomyces anomalus WC 1501 for the production of D-arabitol from pure glycerol

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    D-Arabitol, a five-carbon sugar alcohol, represents a main target of microbial biorefineries aiming to valorize cheap substrates. The yeast Wickerhamomyces anomalus WC 1501 is known to produce arabitol in a glycerol-based nitrogen-limited medium and preliminary fed-batch processes with this yeast were reported to yield 18.0 g/L arabitol

    Feasibility and surgical impact of Z0011 trial criteria in a single-Institution practice.

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    The purpose of this study is the evaluation of clinical and surgical impact of the Z0011 trial criteria on the management of breast cancer (BC) patients undergoing breast conservative surgery (BCS) at the European Institute of Oncology (IEO). We studied 1386 patients who underwent BCS and sentinel lymph node biopsy (SLNB) from July 2016 to July 2018. Clinical evaluation, breast ultrasound, mammogram, and cyto/histological examination were performed for all patients at the time of diagnosis. Frozen sections of the sentinel lymph node (SLN) were not performed for any patient. Patients who underwent neo-adjuvant therapy were excluded. To evaluate the results before and after the introduction of Z0011 criteria, a group of 1425 patients with the same characteristics who underwent BCS and SLNB from July 2013 to July 2015 were analyzed. We studied the characteristics of the patients by nodal status, and we observed that T stage, tumor grade, and lymphovascular invasion were statistically related with the highest rate of positive SLN. Of the 1386 patients who underwent surgery after the introduction of the Z011 trial, 1156 patients (83.4%) had negative SLN, 230 patients (16.6%) had positive SLN. Subsequent axillary lymph node dissection (ALND) was performed in only 7 cases (3.0%). Of the 1425 patients operated before the introduction of the Z0011 trial, 216 patients had subsequent ALND (15%). The reduction in the number of ALND performed after the introduction of Z0011 is statistically significant, and this could result in a remarkable reduction of the comorbidities of our patients

    Similarities and differences between radon surveys across Europe: results from MetroRADON questionnaire

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    Background: As a major cause of lung cancer after smoking, indoor radon is a hazard for human health. Key steps of radon surveys are numerous and include metrology, survey design, development of maps, communication of results to stakeholders, etc. The Council Directive 2013/59/EURATOM introduced new challenges for European Union Member States, such as the identification of radon priority areas, which calls for efforts to improve all the key steps involved in radon surveys. Objective: This study aims to compare existing radon measurement procedures between different European countries and to use the results to optimize the consistency of indoor radon data across Europe. Design: A questionnaire was developed and sent to more than 70 European institutions working in this field to collect information on indoor radon surveys carried out in the respective countries, in order to identify the rationale and methodologies used. Results: A total of 56 questionnaire forms on indoor radon surveys were completed and returned by universities, research institutions, and competent authorities on national and regional surveys from 24 European countries. The replies have been analyzed, and the main findings have been reported, although these replies did not allow to answer all the questions about comparability. Conclusions: From the replies given by the respondents, there is evidence that European indoor radon surveys are comparable regarding measurement methods but not comparable regarding the survey design. Comparability regarding data management, statistical treatment, aggregation, and mapping is unclear on the basis of the replies putting in evidence the need of further information

    Radon levels in dwellings and workplaces: a comparison with data from some European countries

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    Background: According to 2013 European Basic Safety Standards (EU BSS), legal and administrative consequences of having an area declared as radon priority area (RPA) concern workplaces (WP) and public buildings, as well as dwellings (DW). However, RPAs in many cases are defined as higher levels of indoor radon in DW. The reason is that most data are available for DW. So far, indoor radon data for WP (except for schools) and public buildings are scarce. Objective: The objective of this study was to compare indoor radon levels in DW and WP in a given area and to evaluate whether they have different distributions and different average levels. Design: Austria, Finland, Germany, and Italy provided indoor radon data on DW and WP. Data related to WP were aggregated in the same grid, as already done for data on DW, to update the European Indoor Radon Map. Based on 10 km × 10 km grid cells, the same statistics are computed for both datasets. Thus, two structurally equal datasets for each country were generated to be statistically compared. Results and conclusions: Generally, there are numerous indoor radon data on DW than data on WP. Statistical analysis suggests that in all the countries, indoor radon levels – in terms of arithmetic mean (AM) of the natural logarithm-transformed data – in WP and DW are statistically different (P < 0.05), as well as from those referring to schools. The difference in distributions is neither attributable to the effect of geology nor to the effect of different sample sizes. The correlation between aggregated data is positive in the sense that if the mean (over grid cells) radon concentration increases in DW, it increases in WP as well. Compared with DW, in all countries indoor radon levels in WP seem to be statistically different, but the results are not enough to draw final conclusions: on-purpose designed surveys could be a useful tool to better understand this phenomenon

    On harmonization of radon maps

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    Background: Maps are important tools for geographic visualization of the state of the environment with respect to resources as well as to hazards. One of the hazards is indoor radon (Rn), believed to be the most important cause of lung cancer after smoking. In particular, as part of Rn mitigation policy and in compliance with the European Basic Safety Standards, EU Member States have to declare areas with elevated indoor Rn concentration levels. However, as this is done by national authorities according to individually chosen criteria, the resulting maps are not easily comparable.Objective: We aim to identify causes for the lack of compatibility of maps and suggest solutions for the problem.Design: This study draws from experiences of recent research projects, literature, and personal involvement of the authors in the discussions.Results: An overview is given on causes and effects of lack of compatibility between maps. Existing experiences are reported. Options for defining lack of compatibility and for identifying it are discussed. Methods for harmonization, that is, remediating lack of compatibility, are addressed.Conclusions: The difficulty of harmonization increases with the aggregation level of data which support maps. Harmonization is the more difficult, the higher aggregated the data are which support maps. In particular, harmonization of radon priority area maps is technically non-trivial, and theoretical efforts as well as practical tests will have to be undertaken.Special issue - European Radon Week 202

    Optimasi Portofolio Resiko Menggunakan Model Markowitz MVO Dikaitkan dengan Keterbatasan Manusia dalam Memprediksi Masa Depan dalam Perspektif Al-Qur`an

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    Risk portfolio on modern finance has become increasingly technical, requiring the use of sophisticated mathematical tools in both research and practice. Since companies cannot insure themselves completely against risk, as human incompetence in predicting the future precisely that written in Al-Quran surah Luqman verse 34, they have to manage it to yield an optimal portfolio. The objective here is to minimize the variance among all portfolios, or alternatively, to maximize expected return among all portfolios that has at least a certain expected return. Furthermore, this study focuses on optimizing risk portfolio so called Markowitz MVO (Mean-Variance Optimization). Some theoretical frameworks for analysis are arithmetic mean, geometric mean, variance, covariance, linear programming, and quadratic programming. Moreover, finding a minimum variance portfolio produces a convex quadratic programming, that is minimizing the objective function ðð¥with constraintsð ð 𥠥 ðandð´ð¥ = ð. The outcome of this research is the solution of optimal risk portofolio in some investments that could be finished smoothly using MATLAB R2007b software together with its graphic analysis

    Measuring universal health coverage based on an index of effective coverage of health services in 204 countries and territories, 1990–2019 : A systematic analysis for the Global Burden of Disease Study 2019

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    Background Achieving universal health coverage (UHC) involves all people receiving the health services they need, of high quality, without experiencing financial hardship. Making progress towards UHC is a policy priority for both countries and global institutions, as highlighted by the agenda of the UN Sustainable Development Goals (SDGs) and WHO's Thirteenth General Programme of Work (GPW13). Measuring effective coverage at the health-system level is important for understanding whether health services are aligned with countries' health profiles and are of sufficient quality to produce health gains for populations of all ages. Methods Based on the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019, we assessed UHC effective coverage for 204 countries and territories from 1990 to 2019. Drawing from a measurement framework developed through WHO's GPW13 consultation, we mapped 23 effective coverage indicators to a matrix representing health service types (eg, promotion, prevention, and treatment) and five population-age groups spanning from reproductive and newborn to older adults (≥65 years). Effective coverage indicators were based on intervention coverage or outcome-based measures such as mortality-to-incidence ratios to approximate access to quality care; outcome-based measures were transformed to values on a scale of 0–100 based on the 2·5th and 97·5th percentile of location-year values. We constructed the UHC effective coverage index by weighting each effective coverage indicator relative to its associated potential health gains, as measured by disability-adjusted life-years for each location-year and population-age group. For three tests of validity (content, known-groups, and convergent), UHC effective coverage index performance was generally better than that of other UHC service coverage indices from WHO (ie, the current metric for SDG indicator 3.8.1 on UHC service coverage), the World Bank, and GBD 2017. We quantified frontiers of UHC effective coverage performance on the basis of pooled health spending per capita, representing UHC effective coverage index levels achieved in 2019 relative to country-level government health spending, prepaid private expenditures, and development assistance for health. To assess current trajectories towards the GPW13 UHC billion target—1 billion more people benefiting from UHC by 2023—we estimated additional population equivalents with UHC effective coverage from 2018 to 2023. Findings Globally, performance on the UHC effective coverage index improved from 45·8 (95% uncertainty interval 44·2–47·5) in 1990 to 60·3 (58·7–61·9) in 2019, yet country-level UHC effective coverage in 2019 still spanned from 95 or higher in Japan and Iceland to lower than 25 in Somalia and the Central African Republic. Since 2010, sub-Saharan Africa showed accelerated gains on the UHC effective coverage index (at an average increase of 2·6% [1·9–3·3] per year up to 2019); by contrast, most other GBD super-regions had slowed rates of progress in 2010–2019 relative to 1990–2010. Many countries showed lagging performance on effective coverage indicators for non-communicable diseases relative to those for communicable diseases and maternal and child health, despite non-communicable diseases accounting for a greater proportion of potential health gains in 2019, suggesting that many health systems are not keeping pace with the rising non-communicable disease burden and associated population health needs. In 2019, the UHC effective coverage index was associated with pooled health spending per capita (r=0·79), although countries across the development spectrum had much lower UHC effective coverage than is potentially achievable relative to their health spending. Under maximum efficiency of translating health spending into UHC effective coverage performance, countries would need to reach 1398pooledhealthspendingpercapita(US1398 pooled health spending per capita (US adjusted for purchasing power parity) in order to achieve 80 on the UHC effective coverage index. From 2018 to 2023, an estimated 388·9 million (358·6–421·3) more population equivalents would have UHC effective coverage, falling well short of the GPW13 target of 1 billion more people benefiting from UHC during this time. Current projections point to an estimated 3·1 billion (3·0–3·2) population equivalents still lacking UHC effective coverage in 2023, with nearly a third (968·1 million [903·5–1040·3]) residing in south Asia. Interpretation The present study demonstrates the utility of measuring effective coverage and its role in supporting improved health outcomes for all people—the ultimate goal of UHC and its achievement. Global ambitions to accelerate progress on UHC service coverage are increasingly unlikely unless concerted action on non-communicable diseases occurs and countries can better translate health spending into improved performance. Focusing on effective coverage and accounting for the world's evolving health needs lays the groundwork for better understanding how close—or how far—all populations are in benefiting from UHC
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