The Effects of Flooding on Four Common Louisiana Marsh Plants

The marshes of the Louisiana coastline have been deteriorating for decades as plants experience increasing levels of flooding. In this study, we determined the effects of flood duration on four of the most common marsh plants in Louisiana—Spartina alterniflora, Spartina patens, Panicum hemitomon, and Sagittaria lancifolia—by exposing them to different flooding regimes: 0%, 20%, 40%, 60%, 80%, and 100% of the time flooded. Cumulative plant height, soil redox, and soil pH were measured weekly. At the end of the experiment, above- and belowground biomass were measured. Redox measurements showed that the saturated soil (0% flooded) was slightly depleted of oxygen at a redox potential of 300 mV, whereas oxygen was depleted and nitrate and/or manganese used as electron acceptors in all the flooded treatments (20–100% flooded), which had an average soil redox potential near 200 mV. In the saturated treatment, the soil was slightly acidic (pH average 4.7), whereas the flooded treatments had neutral soil acidity (pH average 7.3). Spartina alterniflora biomass was significantly affected by flooding. Spartina alterniflora biomass in the saturated treatment was approximately twice the biomass achieved in any of the flooding treatments. Spartina patens showed a rapid decline in biomass with increased flood duration, reaching the lowest values in treatments that were flooded more than 50% of the time. Although aboveground biomass of Sagittaria lancifolia was not significantly related to flooding regime, belowground biomass decreased with increased flooding duration. The only species that showed no significant response to flooding duration was P. hemitomon. Our results suggest that wetland restoration techniques that reduce flooding frequency are most appropriate for organic marshes dominated by Spartina patens and Spartina alterniflora, whereas these techniques may be less appropriate for organic marshes dominated by Sagittaria lancifolia and P. hemitomon

Study of Deposit Cesium-137 (137Cs) Activity as a Result of Fission Product From the Fukushima Daiichi Nuclear Power Plant at Japan After Earthquake and Tsunami in 2011

Study of deposit Cesium-137 (137Cs) activity as a result of the fission product of Fukushima Daiichi Nuclear Power Plant after earthquake and tsunami in 2011 has been done. The purpose of the present research is to study the deposit 137Cs activity on the land and the Sea of Japan and then to estimate a model of 137Cs distribution on the earth's surface of Japan. The stability of nuclei decay equation is used to obtain a deposit 137Cs activity depending on time, theoretically. The Pasquill-Gifford equation is used to estimate a distribution of 137Cs activity on the earth surface from the original source. The results suggested that Hatachinaka city, the largest measurement point, for about 60 years forward, 137Cs activity levels reach about 54 Bq. In the Sea of Japan at the point of sensor C47, which it has the largest value, the accumulation of deposit 137Cs activity gives about 0.69 Bq at the time of the next 60 years. For the distribution of 137Cs activity, the concentration values at a distance of 200 m from the original source obtained maximum for all case

The Gravity Model of Indonesian Tourism Trade and Investment

This study aimed to determine the performance of tourism investment and trade in Indonesia following the outbreak of COVID-19 and other economic and non-economic factors. Goods and services for Indonesian tourism from 8 sample countries over 26 years were examined using a tourism economy approach and a gravity panel model of the flow of investment and trade. Regarding research originality, the model developed is constructing tourism economic theory applying the Keynesian method. The results showed that economic factors, such as GDP per capita, interest rates, exchange rates, prices, and economic distance, and non-economic factors, such as population, travel alerts, and pandemics, significantly affect investment flows and the tourism trade. Furthermore, tourism competitiveness increased globally in 2019. However, potential economic leakage in FDI and trade were identified. As a result, the government must emphasize long-term and efficient investment and trade in the tourism sector, particularly in the context of systemic shocks such as a pandemic.JEL Classification: C58, D58, Z32, Z38How to Cite:Singagerda, F. S., Desfiandi, A., & Marantika, E.R. (2023). The Gravity Model of Indonesian Tourism Trade and Investment. Etikonomi, 22(1), 143–154. https://doi.org/10.15408/etk.v22i1.25222

Advances in personalized targeted treatment of metastatic melanoma and non-invasive tumor monitoring

Despite extensive scientific progress in the melanoma field, treatment of advanced stage melanoma with chemotherapeutics and biotherapeutics has rarely provided response rates higher than 20%. In the past decade, targeted inhibitors have been developed for metastatic melanoma, leading to the advent of more personalized therapies of genetically characterized tumors. Here we review current melanoma treatments and emerging targeted molecular therapies. In particular we discuss the mutant BRAF inhibitors Vemurafenib and Dabrafenib, which markedly inhibit tumor growth and advance patients’ overall survival. However this response is almost inevitably followed by complete tumor relapse due to drug resistance hampering the encouraging initial responses. Several mechanisms of resistance within and outside the MAPK pathway have now been uncovered and have paved theway for clinical trials of combination therapies to try and overcome tumor relapse. It is apparent that personalized treatment management will be required in this new era of targeted treatment. Circulating tumor cells (CTCs) provide an easily accessible means of monitoring patient relapse and several new approaches are available for the molecular characterization of CTCs. Thus CTCs provide a monitoring tool to evaluate treatment efficacy and early detection of drug resistance in real time.We detail here how advances in the molecular analysis of CTCs may provide insight into new avenues of approaching therapeutic options that would benefit personalized melanoma management

Persistent sleep problems among people in recovery from substance use disorders: a mixed methods study

Background The aims of this study are to examine the one-year trajectory of sleep problems, identify clinical correlates, and describe subjective experiences related to persistent sleep problems during recovery from substance use disorders (SUD). Methods This study builds on a sequential mixed method design. The quantitative component features data from a prospective longitudinal study of 127 poly-SUD patients in the Stavanger area in Norway, while the qualitative component describes a thematic analysis of interviews with 16 persons from this study still experiencing sleep problems after at least one year of abstinence. Results The prevalence of sleep problems at baseline for the whole cohort was 79%. Among the 59 patients who were abstinent after one year, N = 20 (33.9%) had moderate and N = 11 (18.6%) had severe sleep problems. Persistent sleep problems were associated with psychological distress and were experienced as a major challenge in the struggle to stay drug free. Establishing daily routines related to work, school, and care for children were coping strategies for participants with persistent sleep problems. Conclusions Persistent sleep problems are often overlooked in a clinical setting. Based on our findings, these issues pose a major challenge in the struggle to stay drug free. For patients with psychological distress, and lack of responsibilities that established daily routines, sleep difficulties may result in increased risk of drug use episodes that result in relapse. These results argue that screening and evidence-based methods for insomnia and sleep health-programs should be commonplace adjunct intervention for patients with SUDs.publishedVersio

Circulating tumour DNA (ctDNA) as a liquid biopsy for melanoma

Circulating tumour DNA (ctDNA) has emerged as a promising blood-based biomarker for monitoring disease status of patients with advanced cancers. In melanoma, ctDNA has been shown to have clinical value as an alternative tumour source for the detection clinically targetable mutations for the assessment of response to therapy. This review provides a critical summary of the evidence that gives credence to the utility of ctDNA as a biomarker for monitoring of disease status in advanced melanoma and the steps required for its implementation into clinical settings