Enhancing the predictability of radon flux in fractured environments, particularly in confined spaces, is a crucial step towards mitigating the profound health risks associated with radon gas exposure. However, previous models on fluid transport through fractured rock have focused on the relationship between radon flux and aperture in fractures and faults. However, there is paucity of understanding on the influence of rock geo-mechanical properties on radon flux. In addition, there are limited methods of characterizing rocks in relation to radon flux. The numerical model presented in this study incorporated rock properties such as Young's modulus and Poisson ratio with rock aperture to develop a dimensionless radon flux for opening-mode fractures, and five dimensionless parameters (e.g., Geofluid number, Decay number, Fracgen number, Geofrac number, and Geopeclet number) were introduced to characterize fractures in terms of radon transport. Furthermore, these newly discovered relationships were used to conduct a series of flow simulations on fracture networks using the discrete fracture network model (DFN). This model establishes a quantitative framework for predicting radon flux through open-mode fractures and the influence of rock geo-mechanical properties.

The numerical modeling of radon concentrations in the fault zone of the underground excavations at Książ Castle was conducted using a stochastic Discrete Fracture Network (DFN) model. Due to the difficulties related with obtaining the exact fractures in a rock mass, the novel approach used in this study incorporates the stochastic model with known site data. The analysis utilized a dataset comprising long-term measurements of 222Rn activity concentration and geodetic measurements for twelve faults in the Książ unit. The parameters considered in the DFN model are: fracture length, Peclet number (Pe = 0.1 and 1.0, respectively), advection velocities (from 10–8 m/s to 10–6 m/s and from range from 10–7 m/s to 10–4 m/s, respectively), radon diffusion (D = 2.1 × 10–61/s), radon decay constant (λ = 1/s), and radon gas generation (q) along the fractures within the range of 1.5 × 10–3 Bq/m3·s to 3.5 × 10–3 Bq/m3·s. The calibration process obtained the best fit when the radon generation rate was uniformly distributed through the rock mass in addition to incorporating a higher value of radon generation rate (q = 3.0 × 10–3 Bq/m3·s) where elevated radon concentrations have been measured. The modeling results also confirmed that the radon generation rate should always be higher where elevated radon activity concentrations were measured regardless of the measurement period. For the indicated “area” the radon generation rate should be higher from 25% to 37.5% between May–October and 18.5% to 40% between November–April. The influence of fracture zones on the recorded radon activity concentrations was noticeable up to a depth of 15 m. Within this range, the highest values of 222Rn activity concentration, ranging from 1,600 Bq/m3 to 2,000 Bq/m3, were consistently observed regardless of the season. However, as the depth increased, the values of 222Rn activity concentration decreased from 800 Bq/m3 to 400 Bq/m3 and became more dispersed. © The Author(s) 2024.

INTRODUCTION: Routine Immunization (RI) is a key strategy in prevention of vaccine-preventable diseases (VPD). The Nigerian Demographic and Health survey 2013 showed that only 55% of children were fully immunized in Osun State. Historically, efforts to improve uptake of RI focused on health system factors with little attention on maternal related factors. This study assessed mothers´ knowledge, attitude, and perception towards the RI program in Atakumosa West Local Government Area (LGA) of Osun State. METHODS: A total of 750 mothers were enrolled in a household survey using WHO cluster sampling in Atakumosa West LGA. Semi-structured questionnaires were used to obtain data on sociodemographic characteristics, knowledge on RI, attitudes, and perception of mothers towards RI program. Knowledge scores of ≥ 4 points based on six-point domain questions were regarded as good. RESULTS: The mean (±SD) age of the mothers was 27.9 (± 6.1) years; 76% (571/750) had good knowledge of RI and VPD and a majority demonstrated a positive attitude towards the RI program. Antenatal care (ANC) attendance [OR 3.7; 95% CI (2.0 - 6.7)] health facility delivery [OR 1.7 (1.2 - 2.7)]; higher level of education [OR 1.9; 95% CI (1.4 - 2.5)], and mothers´ tetanus toxoid immunization status [OR 4.0 (2.3 - 7.2)] were significantly associated with having good knowledge of the RI program. CONCLUSION: A high proportion of mothers in Atakumosa West LGA of Osun State have good knowledge on childhood RI program. Current efforts at health education in ANC should be sustained and other strategies to improve knowledge on immunization need to be identified.

This study simulates the impact of a shale gas well casing breach near a longwall mine. Field studies are conducted to measure mining-induced permeability changes over the abutment pillar of a longwall mine, and a geomechanical model is developed in 3DEC, a three-dimensional numerical modeling code, to predict the aperture of fractures in the overburden at the study site. The predicted aperture values are used to determine mining-induced permeabilities and the results are compared with the field measurements. These aperture values are provided as inputs into fracture flow code (FFC), which generates a stochastic discrete fracture network (DFN) model for the study site and predicts the potential shale gas flow to the mine. Results from 100 DFN realizations are statistically analyzed using the bootstrapping method to compensate for notable variation in fracture geometry. The results show a significant difference between the gas inflow for nearby panels due to increase in the induced permeability during mining of the second panel. The average gas flow to the mine was calculated as 4.72×10−2 m3/s (49 cfm) for a hypothetical breach at the Sewickley horizon during the first panel mining, 8.97×10−3 m3/s (19 cfm) for a hypothetical breach at the Uniontown horizon during the first panel mining, 2.16×10−1 m3/s (458 cfm) for a hypothetical breach at the Sewickley horizon during the second panel mining, and 8.07×10−2 m3/s (171 cfm) for a hypothetical breach at the Uniontown horizon during the second panel mining. Depending on the mine ventilation system, this could result in methane concentrations exceeding regulatory limits. Hence, these findings provide insights into the potential risk of an unconventional gas well casing breach near a longwall mine under shallow cover. © 2023, This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply.

The integrity of unconventional shale gas well casings positioned in the abutment pillar of a longwall mine could be jeopardized by longwall-induced deformations. Under such scenarios, the surrounding fracture networks could provide pathways for gas flow into the mine creating safety concerns. To provide recommendations for developing guidelines that ensure a safe co-existence of longwall mining and unconventional shale gas production, this study evaluates the impact of parameters that could affect potential shale gas flow into the mine in the event of a casing breach using a discrete fracture network (DFN) model. These parameters are evaluated using a conceptualized DFN realization that is representative of the fractured zone in the overburden, and the range of parameter variations is within values validated with field measurements. The results show that a decrease in fracture aperture (potentially due to longwall-induced stress in the likely vicinity of the breach location) reduces the potential gas flow to the mine by a significantly higher proportion. A 50% decrease in the aperture of the fracture that directly transports the gas from the casing breach location reduces the gas flow to the mine by over 70%. Similarly, changes in the fracture water saturation level significantly affect the gas flow. In all cases, the potential gas flow to the mine is higher if the casing breach occurs at an increased gas well pressure. These findings provide critical information regarding the impact of each of the parameters associated with gas flow in the event of a shale gas casing breach near a longwall mine and could help towards the development of guidelines to ensure a safe coexistence of both industries. © 2022, This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply.

Before the emergence of SARS-CoV-2, the virus that causes COVID-19, influenza activity in the United States typically began to increase in the fall and peaked in February. During the 2021-22 season, influenza activity began to increase in November and remained elevated until mid-June, featuring two distinct waves, with A(H3N2) viruses predominating for the entire season. This report summarizes influenza activity during October 3, 2021-June 11, 2022, in the United States and describes the composition of the Northern Hemisphere 2022-23 influenza vaccine. Although influenza activity is decreasing and circulation during summer is typically low, remaining vigilant for influenza infections, performing testing for seasonal influenza viruses, and monitoring for novel influenza A virus infections are important. An outbreak of highly pathogenic avian influenza A(H5N1) is ongoing; health care providers and persons with exposure to sick or infected birds should remain vigilant for onset of symptoms consistent with influenza. Receiving a seasonal influenza vaccine each year remains the best way to protect against seasonal influenza and its potentially severe consequences.

Longwall-induced deformations could jeopardize the mechanical integrity of shale gas well casings positioned in the abutment pillar of a longwall mine. The in situ and induced fracture networks surrounding the gas well could provide pathways for gas flow into the mine creating safety concerns. Hence, this study by the National Institute for Occupational Safety and Health (NIOSH) develops a discrete fracture network (DFN) model to characterize the fractures in the overburden based on geomechanical analyses of mining-induced fracture apertures at a study site in southwestern Pennsylvania. The apertures from the geomechanical model are used to develop a stochastic DFN model of the site in fracture flow code (FFC). Multiple realizations of the stochastic DFN model that replicate potential fracture geometries are simulated, and the fracture permeability is compared with field measurements. A maximum field measurement of 5.03 1012 m2 (5080 mD) and 3.82 1013 m2 (386 mD) was estimated over the abutment pillar at the Sewickley and Uniontown horizon, respectively. The results show that the average permeabilities from the DFN model agree closely with the field measurements. In addition, the comparison of all the field measurements and 100 DFN realizations show the model is representative of field conditions. These findings provide critical information regarding fracture characteristics in the overburden, which will further be used to predict potential shale gas flow to the mine in the event of a casing breach for an unconventional gas well. 2022, This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply.

The stability of shale gas wells drilled through current and future coal reserves can be compromised by ground deformations due to nearby longwall mining. Depending on the longwall-induced rockmass permeability, the high-pressure explosive gas from the damaged well may reach mine workings and overwhelm the mine ventilation systems. This study uses geomechanical models to estimate the rockmass permeability induced by mining. A two-panel longwall model of a deep, 341-m-cover mining site in southwestern Pennsylvania is constructed in 3DEC to explicitly model the rockmass by a discrete fracture network (DFN) technique. Stress-induced fracture apertures and permeabilities are calculated across the model and are validated against permeability measurements. A fracture flow code (FFC) is developed to use these results to predict potential inflow to the mine should a gas well breach occur. One hundred DFN realizations are simulated, and the results show that for a gas pressure of 2.4 MPa, the average of the predicted inflow rates to this deep-cover mine is 0.006 m3/s, significantly lower than the average inflow of 0.22 m3/s for a shallow-cover mine (145-m deep) studied in the previous work (Khademian, et al. 2021). The result can help assess the potential hazards of a shale gas well breach for mine safety and evaluate the ventilation requirements to mitigate the risk. © 2022, This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply.

The environmental risks associated with casing deformation in unconventional (shale) gas wells positioned in abutment pillars of longwall mines is a concern to many in the mining and gas well industry. With the recent interest in shale exploration and the proximity to longwall mining in Southwestern Pennsylvania, the risk to mine workers could be catastrophic as fractures in surrounding strata create pathways for transport of leaked gases. Hence, this research by the National Institute for Occupational Safety and Health (NIOSH) presents an analytical model of the gas transport through fractures in a low permeable stratum. The derived equations are used to conduct parametric studies of specific transport conditions to understand the influence of stratum geology, fracture lengths, and the leaked gas properties on subsurface transport. The results indicated that the prediction that the subsurface gas flux decreases with an increase in fracture length is specifically for a non-gassy stratum. The sub-transport trend could be significantly impacted by the stratum gas generation rate within specific fracture lengths, which emphasized the importance of the stratum geology. These findings provide new insights for improved understanding of subsurface gas transport to ensure mine safety.

During May 19-September 28, 2019,* low levels of influenza activity were reported in the United States, with cocirculation of influenza A and influenza B viruses. In the Southern Hemisphere seasonal influenza viruses circulated widely, with influenza A(H3) predominating in many regions; however, influenza A(H1N1)pdm09 and influenza B viruses were predominant in some countries. In late September, the World Health Organization (WHO) recommended components for the 2020 Southern Hemisphere influenza vaccine and included an update to the A(H3N2) and B/Victoria-lineage components. Annual influenza vaccination is the best means for preventing influenza illness and its complications, and vaccination before influenza activity increases is optimal. Health care providers should recommend vaccination for all persons aged >/=6 months who do not have contraindications to vaccination (1).

The artemisinin-based combined therapy (ACT) post-treatment illness in Plasmodium falciparum-endemic areas is characterized by vague malaria-like symptoms. The roles of treatment modality, persistence of parasites and host proinflammatory response in disease course are unknown. We investigated the hypothesis that ACT post-treatment syndrome is driven by parasite genetic polymorphisms and proinflammatory response to persisting mutant parasites. Patients were categorized as treated, untreated and malaria-negative. Malaria positive samples were analyzed for Pfcrt, Pfmdr1, K13 kelch gene polymorphisms, while all samples were evaluated for cytokines (TNF-alpha, IL-12p70, IL-10, TGF-beta, IFN-gamma) and corticosteroids (cortisol and dexamethasone) levels. The treated patients exhibited higher levels of parasitemia, TNF-alpha, and cortisol, increased incidence of parasite genetic mutations, and greater number of mutant alleles per patient. In addition, corticosteroid levels declined with increasing number of mutant alleles. TGF-beta levels were negatively correlated with parasitemia, while IL-10 and TGF-beta were negatively correlated with increasing number of mutant alleles. However, IL-12 displayed slight positive correlation and TNF-alpha exhibited moderate positive correlation with increasing number of mutant alleles. Since post-treatment management ultimately results in patient recovery, the high parasite gene polymorphism may act in concert with induced cortisol and TNF-alpha to account for ACT post-treatment syndrome.

Male circumcision reduces the risk for female-to-male human immunodeficiency virus (HIV) transmission by approximately 60% (1) and has become a key component of global HIV prevention programs in countries in Eastern and Southern Africa where HIV prevalence is high and circumcision coverage is low. Through September 2017, the President's Emergency Plan for AIDS Relief (PEPFAR) had supported 15.2 million voluntary medical male circumcisions (VMMCs) in 14 priority countries in Eastern and Southern Africa (2). Like any surgical intervention, VMMC carries a risk for complications or adverse events. Adverse events during circumcision of males aged >/=10 years occur in 0.5% to 8% of procedures, though the majority of adverse events are mild (3,4). To monitor safety and service quality, PEPFAR tracks and reports qualifying notifiable adverse events. Data reported from eight country VMMC programs during 2015-2016 revealed that bleeding resulting in hospitalization for >/=3 days was the most commonly reported qualifying adverse event. In several cases, the bleeding adverse event revealed a previously undiagnosed or undisclosed bleeding disorder. Bleeding adverse events in men with potential bleeding disorders are serious and can be fatal. Strategies to improve precircumcision screening and performance of circumcisions on clients at risk in settings where blood products are available are recommended to reduce the occurrence of these adverse events or mitigate their effects (5).

BACKGROUND: Malaria case management remains a vital component of malaria control strategies. Despite the introduction of national malaria treatment guidelines and scale-up of malaria control interventions in Nigeria, anecdotal evidence shows some deviations from the guidelines in malaria case management. This study assessed factors influencing adherence to malaria diagnosis and treatment guidelines among healthcare workers in public and private sectors in Ogun State, Nigeria. METHODS: A comparative cross-sectional study was carried out among 432 (216 public and 216 private) healthcare workers selected from nine Local Government Areas using a multistage sampling technique. A pre-tested interviewer administered questionnaire was used to collect information on availability and use of malaria Rapid Diagnostic Test (mRDT) and artemisinin combination therapy (ACT), for management of uncomplicated malaria. Adherence was defined as when choice of antimalarials for parasitological confirmed malaria cases was restricted to recommended antimalarial medicines. Association between adherence and independent variables were tested using Chi-square at 5 % level of significance. RESULTS: Malaria RDT was available in 81.9 % of the public health facilities and 19.4 % of the private health facilities (p = 0.001). Its use was higher among public healthcare workers (85.2 %) compared to 32.9 % in private facilities (p = 0.000). Presumptive diagnosis of malaria was higher among private healthcare workers (94.9 %) compared to 22.7 % public facilities (p = <0.0001). The main reason for non-usage of mRDT among private healthcare workers was its perceived unreliability of mRDT (40.9 %). Monotherapy including artesunate (58.3 % vs 12.5 %), amodiaquine (38.9 % vs 8.3 %) and chloroquine (26.4 % vs 4.2 %) were significantly more available in private than public health facilities, respectively. Adherence to guidelines was significantly higher among public healthcare workers (60.6 %) compared to those in private facilities (27.3 %). Availability of antimalarial medicine was the main factor that influenced treatment prescription in both healthcare settings (p = 0.27). However, drug promotion by manufactures (45.8 %) has a major influence on private healthcare workers' prescription practice. CONCLUSION: The findings of this study demonstrate significant difference between public and private healthcare workers on adherence to national malaria diagnosis and treatment guidelines. Interventions to improve private sector engagement in implementation of the guidelines, training and supply of recommended antimalarial medicines should be intensified.

BACKGROUND: Cause-specific mortality data are important to monitor trends in mortality over time. Medical records provide reliable documentation of the causes of deaths occurring in hospitals. This study describes all causes of mortality reported at hospitals in the Federal Capital Territory (FCT) of Nigeria. METHODS: Deaths reported in 15 secondary and tertiary FCT hospitals occurring from January 1, 2005 and December 31, 2008 were identified by a retrospective review of hospital records conducted by the Nigeria Field Epidemiology and Laboratory Program (NFELTP). Data extracted from the records included sociodemographics, geographic area of residence and underlying cause-of-death information. RESULTS: A total of 4,623 deaths occurred in the hospitals. Overall, the top five causes of death reported were: HIV 951 (21%), road traffic accidents 422 (9%), malaria 264 (6%), septicemia 206 (5%), and hypertension 194 (4%). The median age at death was 30 years (range: 0-100); 888 (20%) of deaths were among those less than one year of age. Among children < 1 year, low birth weight and infections were responsible for the highest proportion 131 (15%) of reported mortality. CONCLUSION: Many of the leading causes of mortality identified in this study are preventable. Infant mortality is a large public health problem in FCT hospitals. Although these findings are not representative of all FCT deaths, they may be used to quantify mortality in that occurs in FCT hospitals. These data combined with other mortality surveillance data can provide evidence to inform policy on public health strategies and interventions for the FCT.