Stabilisation by noise on the boundary for a Chafee-Infante equation with dynamical boundary conditions

The stabilisation by noise on the boundary of the Chafee-Infante equation with dynamical boundary conditions subject to a multiplicative It\^o noise is studied. In particular, we show that there exists a finite range of noise intensities that imply the exponential stability of the trivial steady state. This differs from previous works on the stabilisation by noise of parabolic PDEs, where the noise acts inside the domain and stabilisation typically occurs for an infinite range of noise intensities. To the best of our knowledge, this is the first result on the stabilisation of PDEs by boundary noise.Comment: to appear in Discrete and Continuous Dynamical Systems - Series

Origin of organic carbon in the topsoil of Wadden Sea salt marshes

Blue carbon ecosystems, including salt marshes, play an important role in the global carbon cycle because of their high-efficiency storage of organic carbon (OC) in soils. Few studies focus on the origin of OC stored in salt-marsh soils, which is either allochthonous or autochthonous. The origin, however, has important implications for carbon crediting approaches because the alternative fate of allochthonous OC (AllOC), i.e. if it had not accumulated in the blue carbon ecosystem, is unclear. Here, we assessed the origin of OC in 2 mainland salt-marsh sites of the European Wadden Sea, analyzing δ13C of topsoil (0-5 cm) samples, freshly deposited sediment (allochthonous source), and aboveground and belowground biomass of vegetation (autochthonous sources). We tested for effects of geomorphological factors, including elevation and the distance to sediment sources, and of livestock grazing, as the most important land-use form, on the relative contributions of allochthonous versus autochthonous sources to the topsoil OC stock. A negative effect of distance to the creek on the relative contribution of AllOC was found at only 1 of the 2 salt marshes, probably due to differences in micro-topography between the 2 salt marshes. Additionally, the relative contribution of AllOC increased with increasing distance to the marsh edge in areas without livestock grazing, while it decreased in grazed areas. Our findings demonstrate that spatial factors such as surface elevation and distance to a sediment source, which have been found to determine the spatial patterns of sediment deposition, are also important factors determining the relative contribution of AllOC to topsoil OC stocks of salt marshes. Furthermore, we provide the first evidence that livestock grazing can reduce the relative contribution of AllOC to the soil OC stock. These findings thereby yield important implications for carbon crediting and land-use management

Patterns of healthcare seeking among people reporting chronic conditions in rural sub-Saharan Africa: findings from a population-based study in Burkina Faso.

OBJECTIVE: Non-communicable diseases are rapidly becoming one of the leading causes of morbidity and mortality in sub-Saharan Africa. Yet, little is known about patterns of healthcare seeking among people with chronic conditions in these settings. We aimed to explore determinants of healthcare seeking among people who reported at least one chronic condition in rural Burkina Faso. METHODS: Data were drawn from a cross-sectional population-based survey conducted across 24 districts on 52 562 individuals from March to June 2017. We used multinomial logistic regression to assess factors associated with seeking care at a formal provider (facility-based care) or at an informal provider (home and traditional treatment) compared to no care. RESULTS: 1124 individuals (2% of all respondents) reported at least one chronic condition. Among those, 22.8% reported formal care use, 10.6% informal care use, and 66.6% no care. The presence of other household members reporting a chronic condition (RRR = 0.57, 95%-CI [0.39, 0.82]) was negatively associated with seeking formal care. Wealthier households (RRR = 2.14, 95%-CI [1.26, 3.64]), perceived illness severity (RRR = 3.23, 95%-CI [2.22, 4.70]) and suffering from major chronic conditions (RRR = 1.54, 95%-CI [1.13, 2.11]) were positively associated with seeking formal care. CONCLUSION: Only a minority of individuals with chronic conditions sought formal care, with important differences due to socio-economic status. Policies and interventions aimed at increasing the availability and affordability of services for early detection and management in peripheral settings should be prioritised

Diagnostic Yield and Complication Rate of Stereotactic Biopsies in Precision Medicine of Gliomas

Background: An integrated diagnosis consisting of histology and molecular markers is the basis of the current WHO classification system of gliomas. In patients with suspected newly diagnosed or recurrent glioma, stereotactic biopsy is an alternative in cases in which microsurgical resection is deemed to not be safely feasible or indicated. In this retrospective study, we aimed to analyze both the diagnostic yield and the safety of a standardized biopsy technique. Material and Methods: The institutional database was screened for frame-based biopsy procedures (January 2016 until March 2021). Only patients with a suspected diagnosis of glioma based on imaging were included. All tumors were classified according to the current WHO grading system. The clinical parameters, procedural complications, histology, and molecular signature of the tissues obtained were assessed. Results: Between January 2016 and March 2021, 1,214 patients underwent a stereotactic biopsy: 617 (50.8%) for a newly diagnosed lesion and 597 (49.2%) for a suspected recurrence. The median age was 56.9 years (range 5 months−94.4 years). Magnetic resonance imaging (MRI)-guidance was used in 99.3% of cases and additional positron emission tomography (PET)-guidance in 34.3% of cases. In total, stereotactic serial biopsy provided an integrated diagnosis in 96.3% of all procedures. The most frequent diagnoses were isocitrate dehydrogenase (IDH) wildtype glioblastoma (n = 596; 49.2%), oligodendroglioma grade 2 (n = 109; 9%), astrocytoma grade 3 (n = 108; 8.9%), oligodendroglioma grade 3 (n = 76; 6.3%), and astrocytoma grade 2 (n = 66; 5.4%). A detailed determination was successful for IDH 1/2 mutation in 99.4% of cases, for 1p/19q codeletion in 97.4% of cases, for TERT mutation in 98.9% of cases, and for MGMT promoter methylation in 99.1% of cases. Next-generation sequencing was evaluable in 64/67 (95.5%) of cases and DNA methylome analysis in 41/44 (93.2%) of cases. Thirteen (1.1%) cases showed glial tumors that could not be further specified. Seventy-three tumors were different non-glioma entities, e.g., of infectious or inflammatory nature. Seventy-five out of 597 suspected recurrences turned out to be post-therapeutic changes only. The rate of post-procedural complications with clinical symptoms of the Common Terminology Criteria for Adverse Events (CTCAE) grade 3 or higher was 1.2% in overall patients and 2.6% in the subgroup of brainstem biopsies. There was no fatal outcome in the entire series. Conclusion: Image-guided stereotactic serial biopsy enables obtaining reliable histopathological and molecular diagnoses with a very low complication rate even in tumors with critical localization. Thus, in patients not undergoing microsurgical resection, this is a valuable tool for precision medicine of patients with glioma

The value of stereotactic biopsy of primary and recurrent brain metastases in the era of precision medicine

Background: Brain metastases (BM) represent the most frequent intracranial tumors with increasing incidence. Many primary tumors are currently treated in protocols that incorporate targeted therapies either upfront or for progressive metastatic disease. Hence, molecular markers are gaining increasing importance in the diagnostic framework of BM. In cases with diagnostic uncertainty, both in newly diagnosed or recurrent BM, stereotactic biopsy serves as an alternative to microsurgical resection particularly whenever resection is not deemed to be safe or feasible. This retrospective study aimed to analyze both diagnostic yield and safety of an image-guided frame based stereotactic biopsy technique (STX). Material and methods: Our institutional neurosurgical data base was searched for any surgical procedure for suspected brain metastases between January 2016 and March 2021. Of these, only patients with STX were included. Clinical parameters, procedural complications, and tissue histology and concomitant molecular signature were assessed. Results: Overall, 467 patients were identified including 234 (50%) with STX. Median age at biopsy was 64 years (range 29 – 87 years). MRI was used for frame-based trajectory planning in every case with additional PET-guidance in 38 cases (16%). In total, serial tumor probes provided a definite diagnosis in 230 procedures (98%). In 4 cases (1.7%), the pathological tissue did not allow a definitive neuropathological diagnosis. 24 cases had to be excluded due to non-metastatic histology, leaving 206 cases for further analyses. 114 patients (49%) exhibited newly diagnosed BM, while 46 patients (20%) displayed progressive BM. Pseudoprogression was seen in 46 patients, a median of 12 months after prior therapy. Pseudoprogression was always confirmed by clinical course. Metastatic tissue was found most frequently from lung cancer (40%), followed by breast cancer (9%), and malignant melanoma (7%). Other entities included gastrointestinal cancer, squamous cell cancer, renal cell carcinoma, and thyroid cancer, respectively. In 9 cases (4%), the tumor origin could not be identified (cancer of unknown primary). Molecular genetic analyses were successful in 137 out of 144 analyzed cases (95%). Additional next-generation sequencing revealed conclusive results in 12/18 (67%) cases. Relevant peri-procedural complications were observed in 5 cases (2.4%), which were all transient. No permanent morbidity or mortality was noted. Conclusion: In patients with BM, frame-based stereotactic biopsy constitutes a safe procedure with a high diagnostic yield. Importantly, this extended to discerning pseudoprogression from tumor relapse after prior therapy. Thus, comprehensive molecular characterization based on minimal-invasive stereotactic biopsies lays the foundation for precision medicine approaches in the treatment of primary and recurrent BM

With a little help from my friends:physiological integration facilitates invasion of wetland grass Elymus athericus into flooded soils

Tidal wetlands worldwide are undergoing rapid invasions by tall-growing clonal grasses. Prominent examples are invasions by species of the genera Spartina, Phragmites and Elymus. The responsible physiological and ecological drivers of these invasions are poorly understood. Physiological integration (PI) is a key trait of clonal plants, which enables the exchange of resources among ramets. We investigated PI in Elymus athericus, which has been rapidly spreading from high-marsh into low-marsh environments of European salt marshes during the last decades. We applied a nitrogen stable-isotope approach to trace nutrient translocation between ramets in a factorial mesocosm experiment. The experiment was set up to mimic an invasion pattern commonly found in tidal wetlands, i.e. from high-elevated and rarely flooded into low-elevated and frequently flooded microenvironments. We tested for intraspecific variability in PI by including two genotypes of Elymus that naturally occur at different elevations within the tidal frame, a high-marsh (HM) and a low-marsh (LM) genotype. PI strongly increased offspring ramet aboveground and belowground biomass by 62 and 81%, respectively. Offspring ramets under drained conditions had 95% greater belowground biomass than those under flooded conditions. LM genotype offspring ramets produced 27% more aboveground biomass than HM genotypes. Offspring ramets were clearly more enriched in 15N under flooded versus drained conditions; however, this positive effect of flooding on δ15N was only significant in the LM genotype. Our findings demonstrate the importance of PI for the growth of Elymus offspring ramets and thereby for the species' capacity for fast vegetative spread. We show that offspring ramets under stressful flooded conditions are more dependent on nutrient supply from parent ramets than those under drained conditions. Our data furthermore suggest a higher degree of adaptation to flooding via PI in the LM versus HM genotype. In conclusion, we highlight the importance of assessing PI and intraspecific trait variability to understand invasion processes within ecosystems

Towards a harmonized European surveillance for dietary and physical activity indicators in young and adult populations

Background The Policy Evaluation Network proposes a consolidated approach to measure comparable health indicators across European health surveillance systems to evaluate effectiveness of policy action. Methods In a stepwise approach, questionnaire items used by the systems for measuring diet and physical activity data to describe health indicators were identified based on their validity, reliability, and suitability to monitor achievement of health recommendations. They were collated to unified questionnaire modules and discussed bilaterally with representatives of these systems to explore barriers and facilitators for implementation. Also, establishment of a methodological competence platform was proposed, in which the surveillance and monitoring systems agree on the priorities and common quality standards for the harmonization process and to coordinate the integration of questionnaire modules into existing systems. Results In total, seven questionnaire modules were developed, of which two diet and two physical activity modules were proposed for implementation. Each module allows measurement of data reflecting only partial aspects of national and WHO recommendations related to diet and physical activity. Main barriers were the requirements of systems to monitor temporal trends and to minimize costs. Main facilitator for implementation was the systems’ use of questionnaire items that were comparable to the unified modules. Representatives agreed to participate in a methodological competence platform. Conclusion We successfully took first steps in the realization of the roadmap towards a harmonization of European surveillance by introducing unified questionnaire modules allowing the collection of comparable health indicators and by initiating the establishment of a competence platform to guide this process

Entrelazamiento analítico como metodología de investigación en el paradigma emergente

A separação entre pesquisador, aquele que teoriza, e professor, o que coloca as teorias em prática, tem sido questionada nos contextos de pesquisa em educação e ciências humanas, há muito tempo. O professor pode ser teorizador de sua própria prática, reconhecendo o valor do conhecimento daqueles que atuam nas salas de aula. Alinhada a esse argumento está a Pesquisa Docente (do inglês, Teacher Research), que trata de professores-pesquisadores, fundamentada na redefinição das relações estabelecidas entre pesquisa e ensino, de modo que ambas não sejam dissociadas (Freeman, 1998). Este estudo descreve as etapas da Pesquisa Docente, os possíveis instrumentos de coleta de dados e propõe ampliar seus procedimentos de análise por meio do entrelaçamento com a metodologia de análise chamada Processo de Codificação de Auerbach e Silverstein (2003). Dessa forma, este artigo objetiva apresentar o Entrelace Analítico como uma metodologia de pesquisa em educação proposta pelo grupo de pesquisa Tecnologias, Educação e Linguística Aplicada (TECLA), da Universidade Federal de Sergipe (UFS).La separación entre el investigador, el que teoriza, y el profesor, lo que pone en práctica las teorías, ha sido cuestionada en los contextos de investigación en Educación y Ciencias Humanas desde hace mucho tiempo. El profesor puede ser un teórico de su propia práctica, reconociendo el valor del conocimiento de aquellos que trabajan en las aulas. Alineado con este argumento se encuentra la Investigación Docente, que trata con profesores-investigadores y se fundamenta en la redefinición de las relaciones establecidas entre la investigación y la enseñanza, de manera que ambas no se disocien (Freeman, 1998). Este artículo describe las etapas de la Investigación Docente, los posibles instrumentos de recopilación de datos, y propone ampliar sus procedimientos de análisis mediante el entrelazamiento con la metodología de análisis llamada Proceso de Codificación de Auerbach y Silverstein (2003). Por lo tanto, este estudio tiene como objetivo presentar el Entrelazamiento Analítico como una metodología de investigación en educación propuesta por el grupo de investigación Tecnologías, Educación y Lingüística Aplicada (TECLA), de la Universidad Federal de Sergipe (UFS).The distinction between the researcher, the one who theorizes, and the teacher, who puts theories into practice, has long been questioned in the contexts of research in Education and the Humanities. In this sense, the teacher can be a theorist of their own practice recognizing the value of knowledge of those who work in classrooms. Aligned with this argument is Teacher research. This approach states that there are teacher-researchers underpinned on the redefinition of the relations established between research and teaching, so that both are not dissociated (Freeman, 1998). The study describes the stages in Teacher Research, possible instruments of data collection, and it proposes to expand its analysis procedures through intertwining with the method of analysis called Coding Process (Auerbach; Silverstein, 2003). Therefore, this article aims to present Analytical Entwining as a research methodology in education proposed by the research group Technologies, Education, and Applied Linguistics (TECLA), from the Federal University of de Sergipe (UFS)

USO DE PLANTAS MEDICINAIS POR HIPERTENSOS E DIABÉTICOS DE UMA ESTRATÉGIA SAÚDE DA FAMÍLIA RURAL

Objetivo: Investigar o conhecimento sobre as plantas medicinais entre hipertensos e diabéticos de uma equipe da Estratégia Saúde da Família rural de Pelotas. Método: Foi utilizada uma abordagem qualitativa, descritiva e exploratória. Os participantes foram cinco usuários integrantes do grupo HiperDia de uma equipe da Estratégia Saúde da Família rural do município de Pelotas. Os dados foram coletados em setembro de 2014. Os instrumentos utilizados foram a entrevista semiestruturada e a observação sistemática das plantas medicinais, com coleta e registro fotográfico. Para a análise dos dados das entrevistas, foi utilizada proposta operativa. Resultados: Foram citadas 22 plantas medicinais, utilizadas de forma complementar no cuidado à saúde, aliados a outros cuidados como o uso da medicação, cuidados com a alimentação, atividades físicas e bem-estar emocional. A maioria das plantas medicinais referidas teve comprovação com as indicações mencionadas e seu uso frequentemente decorre de costumes tradicionais do meio familiar e/ou da comunidade. Conclusão: Foi evidenciada a importância da troca de saberes com o fortalecimento do vínculo entre a comunidade e os profissionais de saúde e a necessidade crescente de capacitação dos profissionais da saúde para atender essa demanda