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Global G.A.P. compliance has often become a key requirement for farmers to ac- cess high-value global markets. Yet, the global spread of certification is highly un- even among countries. We assess the drivers and dynamics behind these unequal patterns, applying panel data regressions. Findings show that global agricultural trade networks remain relevant, but are no longer sufficient in explaining certifica- tion. Fostering a favourable business environment – via providing secure land tenure and a functioning judicial system – as well as investing in transportation and infor- mation infrastructure may facilitate farmers’ participation in certification schemes. Stringency of existing public regulations is helpful for overcoming entry barriers.
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Open data are important for adding legitimacy and transparency to public sciences. These data have also a potential to be used as a first approach for scientific investigation, such as spatial evaluation of ecosystem services. This paper presents a methodological approach to evaluate the trade-offs between agriculture and supporting ecosystem services based on spatial analysis and open data. The study area is an important agricultural production region in Bahia State, Brazil. The framework was able to establish the spatial interactions between agriculture and ecosystem service provision, while the regional scale was useful in supporting guidelines regarding sustainable land use for agricultural areas.
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The full abstract for this thesis is available in the body of the thesis, and will be available when the embargo expires.
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Despite overall improvements in breast cancer management, breast cancer continues to be a major health challenge worldwide, with high mortality rates. Following initially successful therapies, some cells are able to evade the treatment and remain in the body at undetectable levels (known as minimal residual disease) and could eventually lead to a lethal tumor recurrence. Understanding the nature of this elusive cell population is of a great importance in tumor eradication and relapse prevention. Nevertheless, the intricate mechanistic details about these processes and the nature of these cells remain poorly understood, mainly due to difficulties in obtaining patient material of MRD and being able to study them over the course of treatment. To characterize MRD in breast cancer, we employed an inducible TetO-MYC/TetO-Neu/MMTV-rtTA mouse model and primary 3D cultures of mammary organoids that yield a correlate of MRD upon oncogene silencing. A combination of immunofluorescence, RNA sequencing, lipidomics and metabolomics revealed the unique nature of the residual cells. Despite the phenotypic similarity to the normal population, the residual cells exhibited a distinct transcriptional profile. This profile was also different when compared to the tumor, highlighting the unique properties of the residual cell population. In addition, lipid profiles of the residual cells were also distinguished from both normal and tumor populations. Surprisingly, despite the inactivated oncogenes and seemingly normal phenotype of the residual structures, the residual cells bore a metabolic resemblance to tumor cells. They retained some tumor metabolic hallmarks, which persevered long after the oncogenes were silenced and tumors had regressed. This was demonstrated in our 3D cultures and verified in vivo on histological sections and fresh samples of the mammary glands following tumor regression. Enhanced glycolysis, the urea cycle and NOS2 activity were the most prominent features preserved in the residual cells. As shown in correlation with publicly available microarray datasets of patient samples following neoadjuvant treatment, these traits could be particularly important in MRD of the basal-like HER2 positive and HER2 negative breast cancer subtypes. In conclusion, our findings suggest vast and profound effects of the changes happening over the course of tumor progression, which result in an altered metabolic network even in the absence of oncogene signaling, implying the existence of a “metabolic memory” probably imprinted through the changes in the epigenetic landscape. This phenomenon, particularly its potential driver(s), remains to be investigated. Furthermore, enhanced glycolysis, urea cycle and NOS2 activity in the residual cells compared to the normal, could provide an opportunity to interfere with MRD, offering the potential of preventing tumor recurrences.
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The full abstract for this thesis is available in the body of the thesis, and will be available when the embargo expires.
Data Types:
  • Document
The full abstract for this thesis is available in the body of the thesis, and will be available when the embargo expires.
Data Types:
  • Document
The full abstract for this thesis is available in the body of the thesis, and will be available when the embargo expires.
Data Types:
  • Document
An exploratory study was conducted to analyze combinations of variables that define typological groups that condition the abandonment/continuity of sheep farming in the semi-arid region of Chile. Three typological groups were identified. Group I is made up of middle-aged farmers with the largest flocks. Group II has typical farms from an arid zone, own by elderly male farmers. Group III is located in areas near urban centers and has a greater presence of women farmers. The study allowed to identify the variables that influence the continuity of sheep farmers and to determine strategies that avoid/delay the abandonment of the activity.
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Background: Previous evidence suggests that use of oral contraceptives (OCs), especially during adolescence, may increase women’s vulnerability to depression in the short term. Here, we investigate whether women who had first used OC in adolescence show an increased prevalence of depression in the long term. Methods: We examined 1,236 women in the United States National Health and Nutrition Examination Survey for whom information on depression and age at first OC use was publicly available. We compared women who reported first use of OCs in adolescence to women who had never used OCs and women who had first used OCs in adulthood on 1-year prevalence of major depressive disorder (MDD) assessed by trained interviewers. Results: Compared with women who had used OCs during adolescence, women who had never used OCs were less likely to meet the criteria for MDD within the past year in adulthood [odds ratio (OR) = 0.31, 95% CI = 0.16–0.60], and so were women who only started using OCs in adulthood (OR = 0.54, 95% CI = 0.30–0.95). Third factors that have previously been proposed to explain the relationship between OC use and depression risk such as age at sexual debut, and, importantly, current OC use, did not account for the results in propensity score analyses. Conclusions: We show a long-term association between adolescent OC use and depression risk in adulthood regardless of current OC use. Our findings suggest that adolescence may be a sensitive period during which OC use could increase women’s risk for depression, years after first exposure.
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