28 research outputs found
The effects of variable environmental conditions on growth, nutritional state and protein content in cultivated Saccharina latissima in Norway
No full textCultivation of macroalgae, or seaweed, has been a major industry in Asian countries, predominantly China and Indonesia, for decades. Production of seaweed in Norway is mostly related to research and development (R&D), yet some commercial production exists to this date. Saccharina latissima is considered the most promising species for cultivation in Norway due to its ability to grow in a variety of environmental conditions. The aim of this study was to determine differences in growth, internal nitrate and protein content in S. latissima under a variable of environmental conditions and assess patterns in growth rate. A specific question was if internal NO3--N could describe the nutritional state in the algae under study. Young S. latissima sporophytes were deployed at two depths (1-2 m and 8-9 m) at five experimental locations along the Norwegian coast in February of 2017, and sampling of data for growth and chemical analyses occurred during a period of 23 weeks from April to October of 2017. Light and temperature data indicated an earlier seasonal development in the south compared to the north, and a production period reaching over the summer months was found in the north, while loss of biomass occurred during the summer months in the south. The total nitrogen (N) and N:C ratio in S. latissima both decreased early in the experimental period and increased in the end of the period, suggesting that these variables interacted. A similar pattern of variation as for total N and N:C ratio was found for the amino acid residues and protein content at all locations except for the northernmost location. The internal nitrate content was higher in the seedlings (that had been kept in the hatchery in nutrient rich deep water) than in the sporophytes that were cultivated in the sea. A positive, yet not significant, relationship between relative growth rate (RGR) and internal nitrate was found. The seasonal variation in internal nitrate contents in the sporophytes were more clear at the two northern locations than at the three further south. Seasonal variations were clear at the northern locations while the experiment started too late for them to be measured in the south, indicating a latitudinal gradient. Factors such as photosynthetic active radiation and supply of nutrients possibly limited the growth due to natural seasonal fluctuations in the seawater, though a clear factor that affected the growth rate at the different locations was difficult to identify. The nitrogen-to-protein conversion factor was found to be 3.9 ± 0.1, irrespective of cultivation depth, and it was suggested to use this factor if protein determination by amino acids is not available. A comparison of the N:C ratio and internal nitrate content revealed the possibility to introduce internal nitrate as a proxy for the nutritional state of S. latissima in Norway
The effects of variable environmental conditions on growth, nutritional state and protein content in cultivated Saccharina latissima in Norway
No full textCultivation of macroalgae, or seaweed, has been a major industry in Asian countries, predominantly China and Indonesia, for decades. Production of seaweed in Norway is mostly related to research and development (R&D), yet some commercial production exists to this date. Saccharina latissima is considered the most promising species for cultivation in Norway due to its ability to grow in a variety of environmental conditions. The aim of this study was to determine differences in growth, internal nitrate and protein content in S. latissima under a variable of environmental conditions and assess patterns in growth rate. A specific question was if internal NO3--N could describe the nutritional state in the algae under study. Young S. latissima sporophytes were deployed at two depths (1-2 m and 8-9 m) at five experimental locations along the Norwegian coast in February of 2017, and sampling of data for growth and chemical analyses occurred during a period of 23 weeks from April to October of 2017. Light and temperature data indicated an earlier seasonal development in the south compared to the north, and a production period reaching over the summer months was found in the north, while loss of biomass occurred during the summer months in the south. The total nitrogen (N) and N:C ratio in S. latissima both decreased early in the experimental period and increased in the end of the period, suggesting that these variables interacted. A similar pattern of variation as for total N and N:C ratio was found for the amino acid residues and protein content at all locations except for the northernmost location. The internal nitrate content was higher in the seedlings (that had been kept in the hatchery in nutrient rich deep water) than in the sporophytes that were cultivated in the sea. A positive, yet not significant, relationship between relative growth rate (RGR) and internal nitrate was found. The seasonal variation in internal nitrate contents in the sporophytes were more clear at the two northern locations than at the three further south. Seasonal variations were clear at the northern locations while the experiment started too late for them to be measured in the south, indicating a latitudinal gradient. Factors such as photosynthetic active radiation and supply of nutrients possibly limited the growth due to natural seasonal fluctuations in the seawater, though a clear factor that affected the growth rate at the different locations was difficult to identify. The nitrogen-to-protein conversion factor was found to be 3.9 ± 0.1, irrespective of cultivation depth, and it was suggested to use this factor if protein determination by amino acids is not available. A comparison of the N:C ratio and internal nitrate content revealed the possibility to introduce internal nitrate as a proxy for the nutritional state of S. latissima in Norway
Latitudinal, seasonal and depth-dependent variation in growth, chemical composition and biofouling of cultivated Saccharina latissima (Phaeophyceae) along the Norwegian coast
No full textThe Norwegian coastline covers more than 10° in latitude and provides a range in abiotic and biotic conditions for seaweed farming. In this study, we compared the effects of cultivation depth and season on the increase in biomass (frond length and biomass yield), chemical composition (protein, tissue nitrogen, intracellular nitrate and ash content) and biofouling (total cover and species composition) of cultivated Saccharina latissima at nine locations along a latitudinal gradient from 58 to 69° N. The effects of light and temperature on frond length and biofouling were evaluated along with their relevance for selecting optimal cultivation sites. Growth was greater at 1–2 m than at 8–9 m depth and showed large differences among locations, mainly in relation to local salinity levels. Maximum frond lengths varied between 15 and 100 cm, and maximum biomass yields between 0.2 and 14 kg m−2. Timing of maximum frond length and biomass yield varied with latitude, peaking 5 and 8 weeks later in the northern location (69° N) than in the central (63° N) and southern (58° N) locations, respectively. The nitrogen-to-protein conversion factor (averaged across all locations and depths) was 3.8, while protein content varied from 22 to 109 mg g−1 DW, with seasonality and latitude having the largest effect. The onset of biofouling also followed a latitudinal pattern, with a delayed onset in northern locations and at freshwater-influenced sites. The dominant epibiont was the bryozoan Membranipora membranacea. Our results demonstrate the feasibility of S. latissima cultivation along a wide latitudinal gradient in North Atlantic waters and underscore the importance of careful site selection for seaweed aquaculture.publishedVersio
Design and development process of a youth depression screening m-health application for primary health care workers in South Africa and Zambia : an overview of the MEGA project
No full textLiterature indicates a high prevalence and burden of mental illness in youths world-wide, which may be even higher in low- and middle-income countries (LMIC), such as South Africa and Zambia. Additionally, there is a lack of knowledge regarding youth depression amongst many primary health care (PHC) practitioners. The principal goal of the MEGA project is to provide youth with better access to mental health services and appropriate care, by developing a mental health screening mobile application tool to be used in PHC settings in South Africa and Zambia. In this study, we will use a mixed methods multi-center study design. In phase one, we will investigate the mental health literacy of PHC practitioners to identify areas in need of development. Based on the needs identified, we will develop and test a mobile health application to screen for common youth mental health problems in phase two. In phase three, we will implement and evaluate a tiered education and training program in the use of the m-health application. In the final phase, we will evaluate the acceptability and feasibility of the m-health application in PHC centres across South Africa and Zambia. Evidence suggests that PHC practitioners should routinely consider mental illness when assessing youth. However, common psychiatric disorders remain largely undetected and untreated in PHC settings. By identifying limitations in PHC workers knowledge with regard to youth mental health, we aspire to improve the depression care provided to youth in Southern Africa and Zambia by developing and implementing a locally relevant m-health application.http://www.tandfonline.com/loi/imhn20hj2020Psychiatr
Validation of the Bullying Scale for Adults - Results of the PRONIA-study
No full textBackground: Bullying as a specific subtype of adverse life events is a major risk factor for poor mental health. Although many questionnaires on bullying are available, so far none covers bullying retrospectively throughout school and working life. To close this gap, the Bullying Scale for Adults (BSA) was designed. Methods: Based on data of 622 participants from five European countries collected in the prospective multicenter Personalized Prognostic Tools for Early Psychosis Management (PRONIA) study, we investigated whether the BSA is a reliable and valid measurement for bullying and whether there is a difference across different diagnostic groups of early mental disorders (recent onset depressive/ psychotic patients, patients at clinical high-risk of psychosis) and healthy controls. Results: Bullying experiences were significantly less frequent in healthy controls than in patient groups, with no significant differences between the three clinical groups. The BSA exhibited a high item scale discrimination (r >.3) and very good internal consistency (Cronbach's α =.93). Four factors were identified: 1. Sexual harassment, 2. Emotional Abuse, 3. Physical Abuse, 4. Problems at school. The highly significant correlation between bullying, and childhood adversities and trauma (r =.645, p <.001) indicated good concurrent validity. Discussion: The BSA is the first validated questionnaire that, in retrospective, reliably records various aspects of bullying (incl. its consequences) not only throughout childhood but also working life. It can be used to assess bullying as a transdiagnostic risk factor of mental disorders in different mental disorders, esp. psychosis and depression
The impact of visual dysfunctions in recent-onset psychosis and clinical high-risk state for psychosis
No full textSubtle subjective visual dysfunctions (VisDys) are reported by about 50% of patients with schizophrenia and are suggested to predict psychosis states. Deeper insight into VisDys, particularly in early psychosis states, could foster the understanding of basic disease mechanisms mediating susceptibility to psychosis, and thereby inform preventive interventions. We systematically investigated the relationship between VisDys and core clinical measures across three early phase psychiatric conditions. Second, we used a novel multivariate pattern analysis approach to predict VisDys by resting-state functional connectivity within relevant brain systems. VisDys assessed with the Schizophrenia Proneness Instrument (SPI-A), clinical measures, and resting-state fMRI data were examined in recent-onset psychosis (ROP, n = 147), clinical high-risk states of psychosis (CHR, n = 143), recent-onset depression (ROD, n = 151), and healthy controls (HC, n = 280). Our multivariate pattern analysis approach used pairwise functional connectivity within occipital (ON) and frontoparietal (FPN) networks implicated in visual information processing to predict VisDys. VisDys were reported more often in ROP (50.34%), and CHR (55.94%) than in ROD (16.56%), and HC (4.28%). Higher severity of VisDys was associated with less functional remission in both CHR and ROP, and, in CHR specifically, lower quality of life (Qol), higher depressiveness, and more severe impairment of visuospatial constructability. ON functional connectivity predicted presence of VisDys in ROP (balanced accuracy 60.17%, p = 0.0001) and CHR (67.38%, p = 0.029), while in the combined ROP + CHR sample VisDys were predicted by FPN (61.11%, p = 0.006). These large-sample study findings suggest that VisDys are clinically highly relevant not only in ROP but especially in CHR, being closely related to aspects of functional outcome, depressiveness, and Qol. Findings from multivariate pattern analysis support a model of functional integrity within ON and FPN driving the VisDys phenomenon and being implicated in core disease mechanisms of early psychosis states
Transdiagnostic subgroups of cognitive impairment in early affective and psychotic illness
No full textAbstract: Cognitively impaired and spared patient subgroups were identified in psychosis and depression, and in clinical high-risk for psychosis (CHR). Studies suggest differences in underlying brain structural and functional characteristics. It is unclear whether cognitive subgroups are transdiagnostic phenomena in early stages of psychotic and affective disorder which can be validated on the neural level. Patients with recent-onset psychosis (ROP; N = 140; female = 54), recent-onset depression (ROD; N = 130; female = 73), CHR (N = 128; female = 61) and healthy controls (HC; N = 270; female = 165) were recruited through the multi-site study PRONIA. The transdiagnostic sample and individual study groups were clustered into subgroups based on their performance in eight cognitive domains and characterized by gray matter volume (sMRI) and resting-state functional connectivity (rsFC) using support vector machine (SVM) classification. We identified an impaired subgroup (N ROP = 79, N ROD = 30, N CHR = 37) showing cognitive impairment in executive functioning, working memory, processing speed and verbal learning (all p < 0.001). A spared subgroup (N ROP = 61, N ROD = 100, N CHR = 91) performed comparable to HC. Single-disease subgroups indicated that cognitive impairment is stronger pronounced in impaired ROP compared to impaired ROD and CHR. Subgroups in ROP and ROD showed specific symptom- and functioning-patterns. rsFC showed superior accuracy compared to sMRI in differentiating transdiagnostic subgroups from HC (BACimpaired = 58.5%; BACspared = 61.7%, both: p < 0.01). Cognitive findings were validated in the PRONIA replication sample (N = 409). Individual cognitive subgroups in ROP, ROD and CHR are more informative than transdiagnostic subgroups as they map onto individual cognitive impairment and specific functioning- and symptom-patterns which show limited overlap in sMRI and rsFC. Clinical trial registry name: German Clinical Trials Register (DRKS). Clinical trial registry URL: https://www.drks.de/drks_web/ . Clinical trial registry number: DRKS00005042
MEASUREMENT OF THE MASS AND WIDTH OF THE Z0 PARTICLE FROM MULTI - HADRONIC FINAL STATES PRODUCED IN e+ e- ANNIHILATIONS
No full textFirst measurements of the mass and width of the Z0 performed at the newly commissioned LEP Collider by the DELPHI Collaboration are presented. The measuements are derived from the study of multihadronic final states produced in e+e- annihilations at several energies around the Z0 mass. The values found for the mass and width are M(Z0)=91.06±0.09 (stat) ±0.045 (syst.) GeV and Γ(Z0)=2.42±0.21 (stat.) GeV respectively, froma three-parameter fit to the line shape. A two-parameter fit in the framework of the standard model yields for the number of light neutrino species Nν=2.4±0.4 (stat.) ±0.5 (syst.)0SCOPUS: ar.jinfo:eu-repo/semantics/publishe
