scholarly journals Long-duration seismicity and their relation to Copahue volcano unrest

2022 ◽  
Vol 74 (1) ◽  
Author(s):  
Ivan Melchor ◽  
Javier Almendros ◽  
Marcia Hantusch ◽  
Sergey Samsonov ◽  
Dominique Derauw ◽  
...  

AbstractUnderstanding seismic tremor wavefields can shed light on the complex functioning of a volcanic system and, thus, improve volcano monitoring systems. Usually, several seismic stations are required to detect, characterize, and locate volcanic tremors, which can be difficult in remote areas or low-income countries. In these cases, alternative techniques have to be used. Here, we apply a data-reduction approach based on the analysis of three-component seismic data from two co-located stations operating in different times to detect and analyze long-duration tremors. We characterize the spectral content and the polarization of 355 long-duration tremors recorded by a seismic sensor located 9.5 km SE from the active vent of Copahue volcano in the period 2012–2016 and 2018–2019. We classified them as narrow- (NB) and broad-band (BB) tremors according to their spectral content. Several parameters describe the characteristic peaks composing each NB episode: polarization degree, rectilinearity, horizontal azimuth, vertical incidence. Moreover, we propose two coefficients $$C_P$$ C P and $$C_L$$ C L for describing to what extent the wavefield is polarized. For BB episodes, we extend these attributes and express them as a function of frequency. We compare the occurrence of NB and BB episodes with the volcanic activity (including the level of the crater lake, deformation, temperature, and explosive activity) to get insights into their mechanisms. This comparison suggests that the wavefield of NB tremors becomes more linearly polarized during eruptive episodes, but does not provide any specific relationship between the tremor frequency and volcanic activity. On the other hand, BB tremors show a seasonal behavior that would be related to the activity of the shallow hydrothermal system. Graphical Abstract

2020 ◽  
Vol 35 (5) ◽  
pp. 574-578 ◽  
Author(s):  
Joseph Cuthbertson ◽  
Carol Stewart ◽  
Alison Lyon ◽  
Penelope Burns ◽  
Thompson Telepo

AbstractVolcanoes cause a wide range of hazardous phenomena. Close to volcanic vents, hazards can be highly dangerous and destructive and include pyroclastic flows and surges, ballistic projectiles, lava flows, lahars, thick ashfalls, and gas and aerosol emissions. Direct health impacts include trauma, burns, and exacerbation of respiratory diseases. Far-reaching volcanic hazards include volcanic ashfalls, gas and aerosol dispersion, and lahars. Within Oceania, the island arc countries of Papua New Guinea (PNG), the Solomon Islands, Vanuatu, Tonga, and New Zealand are the most at-risk from volcanic activity. Since 1500ad, approximately 10,000 lives have been lost due to volcanic activity across Oceania, with 39 lives lost since 2000. While volcano monitoring and surveillance save lives, residual risks remain from small, sudden, unheralded eruptions, such as the December 9, 2019 eruption of Whakaari/White Island volcano, New Zealand which has a death toll of 21 at the time of writing. Widespread volcanic ashfalls can affect the habitability of downwind communities by contaminating water supplies, damaging crops and buildings, and degrading indoor and outdoor air quality, as well as disrupting transport and communication networks and access to health services. While the fatality rate due to volcanic eruptions may be low, far greater numbers of people may be affected by volcanic activity with approximately 100,000 people in PNG and Vanuatu displaced since 2000. It is challenging to manage health impacts for displaced people, particularly in low-income countries where events such as eruptions occur against a background of low, variable vaccination rates, high prevalence of infectious diseases, poor sanitation infrastructure, and poor nutritional status. As a case study, the 2017-2018 eruption of Ambae volcano, Vanuatu caused no casualties but triggered two separate mandatory off-island evacuations of the entire population of approximately 11,700 people. On the neighboring island of Santo, a health disaster response was coordinated by local government and provided acute care when evacuees arrived. Involving primary care clinicians in this setting enhanced local capacity for health care provision and allowed for an improved understanding of the impact of displacement on evacuee communities.


Author(s):  
Davor Petrović ◽  
Vida Čulić ◽  
Zofia Swinderek-Alsayed

AbstractJoubert syndrome (JS) is a rare congenital, autosomal recessive disorder characterized by a distinctive brain malformation, developmental delay, ocular motor apraxia, breathing abnormalities, and high clinical and genetic heterogeneity. We are reporting three siblings with JS from consanguineous parents in Syria. Two of them had the same homozygous c.2172delA (p.Trp725Glyfs*) AHI1 mutation and the third was diagnosed prenatally with magnetic resonance imaging. This pathogenic variant is very rare and described in only a few cases in the literature. Multinational collaboration could be of benefit for the patients from undeveloped, low-income countries that have a low-quality health care system, especially for the diagnosis of rare diseases.


2013 ◽  
pp. 121-136
Author(s):  
Duong Pham Bao

The objective of this article is to review the development of the rural financial system in Vietnam in recent years, especially, after Doi moi. There are two opposite schools of thought in the literature on rural credit policies in developing countries. One is the conventional supply-side (government-led) approach while the other is called “a new paradigm” that emphasizes the importance of the viability of financial providers and the well functioning of rural credit markets. Conventional theories of rural finance contend that rural finance in low-income countries is generally accompanied by many failures. Contrary to these theories, rural finance in Vietnam does not encounter the above-mentioned failures so far. Up to the present time, it is progressing well. Using a supply-side approach, methodologically, this study reviews the development of the rural financial system in Vietnam. The significance of this study is to challenge the extreme view of dichotomizing between the old and the new credit paradigms. Analysis in this study contends that a rural financial market that, (1) is initiated and spurred by government; (2) operates principally under market mechanisms; and (3) is strongly supported by rural organizations (semi-formal/informal institutions) can progress stably and well. Therefore, the extremely dichotomizing approach must be avoided.


EMJ Radiology ◽  
2020 ◽  

Retained foreign bodies have become very rare in countries where the safety rules in the operating theatre are very rigorous and follow precise guidelines. There are low-income countries where hospital structures are precarious, in which the implementation of surgical safety rules has only been effective recently. Surgical teams in these countries are not yet well trained in the observance of the guidelines concerning swab count, meaning that textilomas are not uncommon. Abdominal textiloma may be asymptomatic, or present serious gastrointestinal complications such as bowel obstruction, perforation, or fistula formation because of misdiagnosis. It may mimic abscess formation in the early stage or soft tissue masses in the chronic stage. This case report presents a 27-year-old female who underwent an emergency laparotomy in a rural surgical centre for an ectopic pregnancy. Two months later, a swelling had appeared on the left side of her abdomen, gradually increasing in size, which was not very painful but caused digestive discomfort and asthenia. Intermittent fever was described and treated with antibiotics. The patient was referred to a better equipped centre to benefit from a CT scan. A textiloma was strongly suspected on the CT but a left colic mass was not excluded. Laparotomy confirmed the diagnosis of textiloma and the postoperative course was uneventful. Prevention rules must be strengthened in these countries where patients can hardly bear the costs of iterative surgeries for complications that are avoidable.


2020 ◽  
Vol 1 ◽  
pp. 5
Author(s):  
Audu Onyemocho ◽  
Agwa Moses ◽  
Aboh Kisani ◽  
Omole Namben Victoria ◽  
Anejo-Okopi Joseph

Objective: Rabies, one of the oldest and fatal infectious diseases known to human race, is transmitted by infected dogs. The global target of zero dog-mediated rabies human deaths has been set for 2030; however, the realization of this goal poses challenges in most low-income countries where rabies is endemic due to weak surveillance. Dogs have been increasingly deployed for domestic uses over the years, especially for security purposes. This study assessed the assessment of knowledge and practice of vaccination of dogs against rabies by dog owners. Materials and Methods: A cross-sectional community-based study was employed to study 400 dog owners in Makurdi metropolis through multistage sampling techniques. Sighting of valid dog vaccination card was used as criteria for current vaccination. Bivariate analysis was carried out to establish the relationship between the respondent knowledge of rabies and dog vaccination with significant value set at P < 0.05. Results: The mean age of the respondents was 31 (Â ± 0.8) years, majority of them had tertiary and secondary education (40.0% and 39.0%, respectively), 26.0% were traders, and 50.0% were married. Overall, 73.0% of the respondents had good knowledge score, 61.0% had seen at least a rabid dog in their life time, and 74.0% have a history of dog vaccination, but evidence of up to date vaccination of dogs by owners was seen in only 18.0% of all the vaccination cards sighted. The relationship between the educational status of the respondents, their knowledge score, and their dog vaccination was statistically significant (P < 0.05). Conclusion: Knowledge of rabies among dog owners in Makurdi was good, but the practice of dog vaccination was poor. Educational status was a good predictor of practice. Awareness campaign on dog vaccination should be strengthened and adequate measures should be put in place at the veterinary hospitals in Makurdi for vaccination of dogs.


Having broadly stabilized inflation over the past two decades, many policymakers in sub-Saharan Africa are now asking more of their monetary policy frameworks. They are looking to avoid policy misalignments and respond appropriately to both domestic and external shocks, including swings in fiscal policy and spikes in food and export prices. In many cases they are finding current regimes—often characterized as ‘money targeting’—lacking, with opaque and sometimes inconsistent objectives, inadequate transmission of policy to the economy, and difficulties in responding to supply shocks. At the same time, little existing research on monetary policy is targeted to low-income countries. What do we know about the empirics of monetary transmission in low-income countries? (How) Does monetary policy work in countries characterized by a huge share of food in consumption, underdeveloped financial markets, and opaque policy regimes? (How) Can we use methods largely derived in advanced countries to answer these questions? And (how) can we use the results to guide policymakers? This book draws on years of research and practice at the IMF and in central banks from the region to shed empirical and theoretical light on these questions and to provide practical tools and policy guidance. A key feature of the book is the application of dynamic general equilibrium models, suitably adapted to reflect key features of low-income countries, for the analysis of monetary policy in sub-Saharan African countries.


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