155 research outputs found

    Life cycle assessment of fish oil substitute produced by microalgae using food waste

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    Fish oil has been used in conventional aquaculture for decades, despite the known links between increasing global demand for fish and depletion of natural resources and vital ecosystems (FAO, 2020, 2019). Alternative feed ingredients, including algae oil rich in docosahexaenoic acid (DHA), has therefore been increasingly used to substitute traditional fish oil. Heterotrophic algae cultivation in bioreactors can be supported by a primary carbon feedstock recovered from food waste, a solution that could reduce environmental impacts and support the transition towards circular food systems. This study used life cycle assessment to quantify environmental impact of DHA produced by the heterotrophic algae Crypthecodinium cohnii, using short-chain carboxylic acids derived from dark fermentation of food waste. The future potential of DHA from algae was evaluated by comparing the environmental impact to that of DHA from Peruvian anchovy oil. With respect to global warming, terrestrial acidification, freshwater eutrophication and land use, algae oil inferred -52 ton CO2eq, 3.5 ton SO2eq, -94 kg Peq, 2700 m2 eq, respectively per ton DHA. In comparison, the impact per ton DHA from fish oil was -15 ton CO2eq, 3.9 ton SO2eq, -97 kg Peq and 3200 m2 eq. Furthermore, algae oil showed lower climate impact compared to canola and linseed oil. By including Ecosystem damage as indicator for ecosystem quality at endpoint level, the important aspect of biodiversity impact was accounted for. Although the method primarily accounts for indirect effects on biodiversity, DHA from algae oil showed lower Ecosystem damage compared to fish oil even when future energy development, optimized production, increased energy demand and effects on biotic resources were considered via sensitivity analyses. As the results suggest, algae oil holds a promising potential for increased sustainability within aquaculture, provided that continued development and optimization of this emerging technology is enabled through active decision-making and purposeful investments

    Life cycle-based environmental impacts of energy system transformation strategies for Germany: Are climate and environmental protection conflicting goals?

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    In the development of climate-friendly energy system transformation strategies it is often ignored that environmental protection encompasses more than climate protection alone. There is therefore a risk of developing transformation strategies whose climate friendliness comes at the expense of higher other environmental impacts. Consequently, an assessment of environmental impacts of energy system transformation strategies is required if undesired environmental side effects of the energy system transformation are to be avoided and transformation strategies are to be developed that are both climate and environmentally friendly. In this paper, ten structurally different transformation strategies for the German energy system were re-modeled (in a harmonized manner). Five of these scenarios describe pathways for a reduction of direct, energy related CO2_2 emissions by 80%, the other five by 95%. Life cycle-based environmental impacts of the scenarios were assessed by coupling the scenario results with data from a life cycle inventory database focusing on energy and transport technologies. The results show that the transformation to a climate-friendly energy system reduces environmental impacts in many impact categories. However, exceptions occur with respect to the consumption of mineral resources, land use and certain human health indicators, which could increase with decreasing CO2_2 emissions. The comparison of environmental impacts of moderately ambitious strategies (80% CO2_2 reduction) with very ambitious strategies (95% CO2_2 reduction) shows that there is a risk of increasing environmental impacts with increasing climate protection, although very ambitious strategies do not necessarily come along with higher environmental impacts than moderately ambitious strategies. A reduction of environmental impacts could be achieved by a moderate and – as far as possible – direct electrification of heat and transport, a balanced technology mix for electricity generation, by reducing the number and size of passenger cars and by reducing the environmental impacts from the construction of these vehicles

    Challenges and status: Single-use bioreactors for microbial processes

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    Nowadays single-use bioreactors are fully accepted in the biopharmaceutical industry. Reactors up to 2000L working volume are commonly used. However, these bioreactors are limited in terms of mass-transfer and mixing capabilities and therefore only suited for application in mammalian cell culture. Single-use processing offers many benefits like cost reduction, flexibility, reduction of contamination risks, etc. These benefits apply for both microbial processes as for mammalian processes. Additionally, for the use of marine microorganisms the application of single-use bioreactors (SUB) offers a possibility to circumvent problem of corrosion which occurs in steel bioreactors due to the high chloride ion concentration in the media when the early stage of process development or the need for multi-purpose devices does not allow the investment in process-specific infrastructure. However, marine production processes can demand for high gas mass transfer rates, e.g. in the case of Crypthecodinium cohnii, a heterotrophic algae applied for the production of the polyunsatured fatty acid docosahexaenoic acid. C. cohnii cells are highly sensitive to shear-forces. In general, unfavorable cultivation conditions lead to a high batch-to-batch variation, and thus to a random process development and optimization. In this paper we describe experience of the use of different single use bioreactors for the high cell density cultivation of C. cohnii and other microorganisms. Specific parameters we looked at were the gas transfer efficiency as an important parameter for high cell and product yields as well as the opportunity for expansion of the culture over a wide volume range. Among various SUBs, which were tested, only the 2-D wave-mixed CELL-tainer® showed a high oxygen mass transfer at comparably low shear forces, and hence provided a very vital culture.1, 2 In order to broaden the range of the working volume, expansion channel blocks were applied, which allow performing cultivations from 150 ml to 20 L without reinocculation. However, the scalability of a wave-mixed system is challenging due to the restricted knowledge of classical engineering parameters. Therefore, the physiologic and morphologic constitution of the cells was considered to prove the suitability of the SUBs at scales from the mL to the 120 L range. Therefore a novel on-line photo-optical instrument (SOPAT) for the analysis of cell shapes, and lipid droplet accumulation was applied. It allowed a direct insight into the stage of growth, population homogeneity, and fatty acid production. Although it is hardly feasible to maintain identical cultivation conditions from the µL to the m³ scale, the combination of engineering parameters and process analytical tools led to the overall achievement of suitable cultivation conditions. The presented on-line method in relation to the developmental strategy over different scales is relevant for the development of plant and other cell culture processes, while contributing to reduced development times and costs

    Primary Urothelial Carcinoma of the Ureter: 11-Year Experience in Taipei Veterans General Hospital

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    BackgroundUrothelial carcinoma of the upper urinary tract is relatively rare, occurring in 5% of all urothelial tumors. Ureteral urothelial carcinoma is even less common than that of the renal pelvis, accounting for about 25% of all upper urinary tract tumors. The aim of this study was to evaluate the clinical behavior, survival, recurrence and prognostic information of primary ureteral urothelial carcinoma from our 11 years of experience at the Taipei Veterans General Hospital.MethodsWe retrospectively reviewed 111 patients with ureteral urothelial carcinoma who had been treated in our hospital between January 1993 and December 2003. Tumor staging was according to the 2002 AJCC TNM classification and stage groupings. Patients with stage 0a and stage 0is were categorized as stage 0a/is, and patients with pathologic T stage pTa and pTis were categorized as pTa/is for statistical analysis. The Kaplan-Meier method was used for survival analysis.ResultsThere were 69 males and 42 females, with a mean age of 70.5 ± 9.4 years at diagnosis. Of the 111 patients, 5 presented with stage 0a/is, 38 with stage I, 23 with stage II, 21 with stage III, and 24 with stage IV. Nephroureterectomy with bladder cuff excision was performed in 78 patients, 12 patients received segmental resection of the ureter, 4 received ureteroscopic laser coagulation, and 17 underwent chemotherapy or radiotherapy or both. Tumors were located on the left side in 53 patients, on the right in 53, and bilaterally in 5. The most frequent initial presenting symptom was gross hematuria (65%). The mean postoperative follow-up period was 49.3 months. Disease recurrence in the nephroureterectomy group occurred in 36 patients (46.2%), with 17 (21.8%) at the urinary bladder, 2 (2.6%) at the retroperitoneum, 1 (1.3%) at the contralateral ureter, 6 (7.7%) with distant metastases to the lung, bone, distant lymph nodes or liver, and 10 (12.8%) at multiple sites. The 5-year cancer-specific survival rate was 100% for pTa/is, 95.2% for pT1, 69.4% for pT2, and 43.8% for pT3. All 3 pT4 cases died of cancer in a median of 12 months. Significant prognostic factors for cancer-specific survival by univariate analysis were pT (p = 0.00001), stage (p = 0.00001), type of treatment (p = 0.00001) and grade (p = 0.0001). On multivariate analysis, only stage (p = 0.0001) and grade (p = 0.014) were significant for cancer-specific and overall survival. Stage (p = 0.0001), pT (p =0.0001) and grade (p = 0.026) were also significant prognostic factors of recurrence in multivariate analysis.ConclusionOur experience showed that patients with pTa/is and pT1 tumors treated with radical surgery have excellent prognoses. Tumor stage and grade are the only significant prognostic factors for both cancer-specific and overall survival

    Integrated multidimensional sustainability assessment of energy system transformation pathways

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    Sustainable development embraces a broad spectrum of social, economic and ecological aspects. Thus, a sustainable transformation process of energy systems is inevitably multidimensional and needs to go beyond climate impact and cost considerations. An approach for an integrated and interdisciplinary sustainability assessment of energy system transformation pathways is presented here. It first integrates energy system modeling with a multidimensional impact assessment that focuses on life cycle-based environmental and macroeconomic impacts. Then, stakeholders’ preferences with respect to defined sustainability indicators are inquired, which are finally integrated into a comparative scenario evaluation through a multi-criteria decision analysis (MCDA), all in one consistent assessment framework. As an illustrative example, this holistic approach is applied to the sustainability assessment of ten different transformation strategies for Germany. Applying multi-criteria decision analysis reveals that both ambitious (80%) and highly ambitious (95%) carbon reduction scenarios can achieve top sustainability ranks, depending on the underlying energy transformation pathways and respective scores in other sustainability dimensions. Furthermore, this research highlights an increasingly dominant contribution of energy systems’ upstream chains on total environmental impacts, reveals rather small differences in macroeconomic effects between different scenarios and identifies the transition among societal segments and climate impact minimization as the most important stakeholder preferences

    Heterozygous Loss-of-Function SEC61A1 Mutations Cause Autosomal-Dominant Tubulo-Interstitial and Glomerulocystic Kidney Disease with Anemia

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    Autosomal-dominant tubulo-interstitial kidney disease (ADTKD) encompasses a group of disorders characterized by renal tubular and interstitial abnormalities, leading to slow progressive loss of kidney function requiring dialysis and kidney transplantation. Mutations in UMOD, MUC1, and REN are responsible for many, but not all, cases of ADTKD. We report on two families with ADTKD and congenital anemia accompanied by either intrauterine growth retardation or neutropenia. Ultrasound and kidney biopsy revealed small dysplastic kidneys with cysts and tubular atrophy with secondary glomerular sclerosis, respectively. Exclusion of known ADTKD genes coupled with linkage analysis, whole-exome sequencing, and targeted re-sequencing identified heterozygous missense variants in SEC61A1—c.553A>G (p.Thr185Ala) and c.200T>G (p.Val67Gly)—both affecting functionally important and conserved residues in SEC61. Both transiently expressed SEC6A1A variants are delocalized to the Golgi, a finding confirmed in a renal biopsy from an affected individual. Suppression or CRISPR-mediated deletions of sec61al2 in zebrafish embryos induced convolution defects of the pronephric tubules but not the pronephric ducts, consistent with the tubular atrophy observed in the affected individuals. Human mRNA encoding either of the two pathogenic alleles failed to rescue this phenotype as opposed to a complete rescue by human wild-type mRNA. Taken together, these findings provide a mechanism by which mutations in SEC61A1 lead to an autosomal-dominant syndromic form of progressive chronic kidney disease. We highlight protein translocation defects across the endoplasmic reticulum membrane, the principal role of the SEC61 complex, as a contributory pathogenic mechanism for ADTKD

    Seeing like the international community: how peacebuilding failed (and survived) in Tajikistan

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    Post-print version. 18 month embargo by the publisher. Article will be released April 2010.The international community claims transformative power over post-conflict spaces via the concept of peacebuilding. International actors discursively make space for themselves in settings such as the Central Asian state of Tajikistan which endured a civil war during the 1990s and has only seen an end to widespread political violence in recent years. With the work of James C. Scott, this paper challenges the notion that post-conflict spaces are merely the objects of international intervention. It reveals how, even in cases of apparent stability such as that of Tajikistan, international actors fail to achieve their ostensible goals for that place yet make space for themselves in that place. International peacebuilders may provide essential resources for the re-emergence of local forms of order yet these symbolic and material resources are inevitably re-interpreted and re-appropriated by local actors to serve purposes which may be the opposite of their aims. However, despite this ‘failure’ of peacebuilding it nevertheless survives as a discursive construction through highly subjective processes of monitoring and evaluation. So maintained, peacebuilding is a constitutive element of world order where the necessity of intervention for humanitarian, democratic and statebuilding ends goes unchallenged. This raises the question of what or where – in spatial terms – is the locus of international intervention: the local recipients of peacebuilding programmes (who are the ostensible targets) or ‘the International Community’ itself (whose space is re-inscribed as that of an imperfect but necessary regulator of world order)

    Beyond BMI for self-estimates of body size and shape: A new method for developing stimuli correctly calibrated for body composition

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    Accurate self-assessment of body shape and size plays a key role in the prevention, diagnosis, and treatment of both obesity and eating disorders. These chronic conditions cause significant health problems, reduced quality of life, and represent a major problem for health services. Variation in body shape depends on two aspects of composition: adiposity and muscularity. However, most self-assessment tools are unidimensional. They depict variation in adiposity only, typically quantified by the body mass index. This can lead to substantial, and clinically meaningful, errors in estimates of body shape and size. To solve this problem, we detail a method of creating biometrically valid body stimuli. We obtained high-resolution 3D body shape scans and composition measures from 397 volunteers (aged 18–45 years) and produced a statistical mapping between the two. This allowed us to create 3D computer-generated models of bodies, correctly calibrated for body composition (i.e., muscularity and adiposity). We show how these stimuli, whose shape changes are based on change in composition in two dimensions, can be used to match the body size and shape participants believe themselves to have, to the stimulus they see. We also show how multivariate multiple regression can be used to model shape change predicted by these 2D outcomes, so that participants’ choices can be explained by their measured body composition together with other psychometric variables. Together, this approach should substantially improve the accuracy and precision with which self-assessments of body size and shape can be made in obese individuals and those suffering from eating disorders

    SecA, a remarkable nanomachine

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    Biological cells harbor a variety of molecular machines that carry out mechanical work at the nanoscale. One of these nanomachines is the bacterial motor protein SecA which translocates secretory proteins through the protein-conducting membrane channel SecYEG. SecA converts chemically stored energy in the form of ATP into a mechanical force to drive polypeptide transport through SecYEG and across the cytoplasmic membrane. In order to accommodate a translocating polypeptide chain and to release transmembrane segments of membrane proteins into the lipid bilayer, SecYEG needs to open its central channel and the lateral gate. Recent crystal structures provide a detailed insight into the rearrangements required for channel opening. Here, we review our current understanding of the mode of operation of the SecA motor protein in concert with the dynamic SecYEG channel. We conclude with a new model for SecA-mediated protein translocation that unifies previous conflicting data
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