The effect of uterine closure technique on cesarean scar niche development after multiple cesarean deliveries.

OBJECTIVES: To use saline infusion sonohysterography (SIS) to evaluate the effect of uterine closure technique on niche formation after multiple cesarean deliveries (CDs). METHODS: Patients with at least one prior CD were evaluated for niche via SIS. Subgroups of any number repeat CD (>1 prior), lower-order CD (<4 prior), and higher-order CD (≥4 prior) were analyzed, stratifying by hysterotomy closure technique at last cesarean preceding imaging; techniques included Technique A (endometrium-free double-layer closure) and Technique B (single- or double-layer routine endo-myometrial closure). Niche defects were quantified (depth, length, width, and residual myometrial thickness). The primary outcome was clinically significant niche, defined as depth >2 mm. Statistical analysis was performed using chi-square, ANOVA, t-test, Kruskal-Wallis, and multiple logistic regression, with p-values of <0.05 were statistically significant. RESULTS: A total of 172 post-cesarean SIS studies were reviewed: 105 after repeat CDs, 131 after lower-order CDs, and 41 after higher-order CDs. Technique A was associated with a shorter interval to imaging and more double-layer closures. Technique B was associated with more clinically significant niches across all subgroups, and these niches were significantly longer and deeper when present. Multiple logistic regression demonstrated a 5.6, 8.1, and 11-fold increased adjusted odds of clinically significant niche following Technique B closure in the repeat CD (p<0.01), lower-order CD (p<0.001), and higher-order CD (p=0.04) groups, respectively. CONCLUSIONS: While multiple CDs are known to increase risk for niche defects and their sequelae, hysterotomy closure technique may help to reduce niche development and severity.

Enhanced recovery after cesarean from the patient perspective: a prospective study of the ERAC Questionnaire (ERAC-Q).

OBJECTIVES: To evaluate the impact of an Enhanced Recovery After Cesarean (ERAC) protocol on the post-cesarean recovery experience using a validated ten-item questionnaire (ERAC-Q). METHODS: This is a prospective cohort study of patients completing ERAC quality-of-life questionnaires (ERAC-Q) during inpatient recovery after cesarean delivery (CD) between October 2019 and September 2020, before and after the implementation of our ERAC protocol. Patients with non-Pfannenstiel incision, ICU admission, massive transfusion, bowel injury, existing chronic pain disorders, acute postpartum depression, or neonatal demise were excluded. The ERAC-Q was administered on postoperative day one and day of discharge to the pre- and post-ERAC implementation cohorts, rating aspects of their recovery experience on a scale of 0 (best) to 10 (worst). The primary outcome was ERAC-Q scores. Statistical analysis was performed with SAS software. RESULTS: There were 196 and 112 patients in the pre- and post-ERAC cohorts, respectively. The post-ERAC group reported significantly lower total ERAC-Q scores compared to the pre-ERAC group, reflecting fewer adverse symptoms and greater perceived recovery on postoperative day one (1.6 [0.7, 2.8] vs. 2.7 [1.6, 4.3]) and day of discharge (0.8 [0.3, 1.5] vs. 1.4 [0.7, 2.2]) (p<0.001). ERAC-Q responses did not predict the time to achieve objective postoperative milestones. However, worse ERAC-Q pain and total scores were associated with higher inpatient opiate use. CONCLUSIONS: ERAC implementation positively impacts patient recovery experience. The administration of ERAC-Q can provide real-time feedback on patient-perceived recovery quality and how healthcare protocol changes may impact their experience.

Elevated Radium Activity in a Hydrocarbon-Contaminated Aquifer.

Hydrocarbon spills that reach the subsurface can modify aquifer geochemical conditions. Biogeochemical zones typically form proximal to the source zone that include iron (Fe(III)) and manganese (Mn(III/IV)) (hydr)oxide reduction, with potential to release associated geogenic contaminants to groundwater. Here, multi-level monitoring systems are used to investigate radium (226Ra, 228Ra) activities in an aquifer contaminated with a mixture of chlorinated solvents, ketones, and aromatics occurring as a dense non-aqueous phase liquid in the source zone. 226Ra activities are up to 10 times higher than background 60 m downgradient from the source zone, where pH is lower, total dissolved solid concentrations are higher, and conditions are methanogenic. Correlations indicate that Fe and Mn (hydr)oxide reduction and sorption site competition are likely responsible for elevated Ra activities within the dissolved phase plume. 226Ra activities return to background within the Fe(III)/SO42--reducing zone 600 m downgradient from the source, near the middle of the dissolved phase plume. Geochemical models indicate that sorption to secondary phases (e.g., clays) is important in sequestering Ra within the plume. Although maximum Ra activities within the plume are well below the U.S. drinking water standard, elevated activities compared to background emphasize the importance of investigating Ra and other trace elements at hydrocarbon-impacted sites.

Development of the ¡Vamos por Mas! parenting program to prevent substance use among Chilean adolescents.

In Chile, the prevalence of tobacco, alcohol and drug use among adolescents is very high. Decades of research indicate that parenting interventions reduce these risky behaviors. However, there are no parenting interventions validated in Chile to prevent adolescent substance use. This article reports the development of the ¡Vamos por Mas! (¡VxM!) program following the recommendations of the Medical Research Council's framework for designing and evaluating complex interventions. After identifying key intervention components, a preliminary version of a substance-use prevention program was designed. The preliminary intervention targeted families with adolescents in fifth and sixth grade and had four components: personalized feedback, in-person workshops, virtual engagement, and family support, to deliver positive-youth development and family-strengthening content. Then, students, guardians, school staff and community experts from different school systems (N = 111) evaluated the preliminary version of the program through a convergent parallel mixed methods study, including focus groups (N = 14) and surveys (N = 101). In general, all participants had positive perceptions of the program and valued its purpose, strategies, objectives and contents. Suggestions included expanding the purpose to promote healthy relationships, focusing on schools with low and intermediate socioeconomic vulnerability, including self-control content, removing the personalized feedback component and adding two additional components: school partnership and external supervision, among other improvements. With this information, the final version of the ¡VxM! program was developed. After a rigorous intervention development process, the ¡VxM! program is ready to be piloted and evaluated in a randomized trial.

Chile has high rates of tobacco, alcohol and drug use among adolescents. Parenting interventions have shown to reduce these risky behaviors. However, there are no parenting interventions validated in Chile to prevent adolescent substance use. This article reports the development of the ¡Vamos por Mas! (¡VxM!) program to strengthen family relations and prevent adolescent substance use following the recommendations of the Medical Research Council's framework for designing and evaluating complex interventions. In the first phase, key intervention components were identified. Then, a preliminary version of the intervention was designed. In the second phase, perceptions of key stakeholders were collected through focus groups (N = 14) and surveys (N = 101) including adolescents, guardians, school staff and community experts. These participants evaluated the preliminary version of the program and provided feedback. In the final phase of the intervention development process, stakeholder opinions were integrated into the proposal. The final version of the ¡VxM! program included five components: (i) school partnership, (ii) in-person workshops, (iii) virtual engagement, (iv) family support and (v) external supervision. This version is ready to be piloted to evaluate feasibility and preliminary efficacy, before being assessed in a randomized trial.

The Impact of Uterine Incision Closure Techniques on Post-cesarean Delivery Niche Formation and Size: Sonohysterographic Examination of Nonpregnant Women.

OBJECTIVE: To compare the prevalence and size of residual niche in the nongravid uterus following Cesarean delivery (CD) with different hysterotomy closure techniques (HCTs). METHODS: Saline infusion sonohysterogram (SIS) was performed in women after one prior CD, documenting the presence or absence of a postoperative niche and measuring its depth, width, length, and residual myometrial thickness. Women were grouped by HCT: Technique A (endometrium-free) and Technique B (routine non-endometrium-free). The primary outcome was the prevalence of a clinically significant niche, defined as a depth of >2 mm. HCT groups were compared using χ2 , T-test (ANOVA), and analyzed using logistic regression and two-sided test (P < .05). RESULTS: Forty-five women had SIS performed, 25 and 20 via Technique A and B, respectively. Technique groups varied by average interval time from CD to SIS (13.6 versus 74.5 months, P = 0.006) but were otherwise similar. Twenty niches were diagnosed, 85% of which were clinically significant, including five following Technique A, nine following Technique B with double-layer closure, and three following Technique B with single-layer (P = .018). The average niche depth was 2.4 mm and 4.9 mm among the two-layer subgroups following Techniques A and B, respectively (P = .005). A clinically significant niche development was six times higher with Technique B when compared to Technique A (OR 6.0, 95% CI 1.6-22.6, P = .008); this significance persisted after controlling for SIS interval on multivariate analysis (OR 4.4, 95% CI 1.1-18.3, P = .04). The average niche depth was 5.7 ± 2.9 mm following Technique B with single-layer. CONCLUSION: Hysterotomy closure techniques determine the prevalence of post-Cesarean delivery niche formation and size. Exclusion of the endometrium at uterine closure reduces the development of significant scar defects.

Loss of Consciousness is Associated with Elevated Cognitive Intra-Individual Variability Following Sports-Related Concussion.

OBJECTIVE: The purpose of this study was to evaluate whether loss of consciousness (LOC), retrograde amnesia (RA), and anterograde amnesia (AA) independently influence a particular aspect of post-concussion cognitive functioning-across-test intra-individual variability (IIV), or cognitive dispersion. METHOD: Concussed athletes (N = 111) were evaluated, on average, 6.04 days post-injury (SD = 5.90; Mdn = 4 days; Range = 1-26 days) via clinical interview and neuropsychological assessment. Primary outcomes of interest included two measures of IIV-an intra-individual standard deviation (ISD) score and a maximum discrepancy (MD) score-computed from 18 norm-referenced variables. RESULTS: Analyses of covariance (ANCOVAs) adjusting for time since injury and sex revealed a significant effect of LOC on the ISD (p = .018, ηp2 = .051) and MD (p = .034, ηp2 = .041) scores, such that athletes with LOC displayed significantly greater IIV than athletes without LOC. In contrast, measures of IIV did not significantly differ between athletes who did and did not experience RA or AA (all p > .05). CONCLUSIONS: LOC, but not RA or AA, was associated with greater variability, or inconsistencies, in cognitive performance acutely following concussion. Though future studies are needed to verify the clinical significance of these findings, our results suggest that LOC may contribute to post-concussion cognitive dysfunction and may be a risk factor for less efficient cognitive functioning.

A cluster randomized trial of interferon ß-1a for the reduction of transmission of SARS-Cov-2: protocol for the Containing Coronavirus Disease 19 trial (ConCorD-19).

BACKGROUND: SARS-CoV-2 infection rapidly spreads in populations due to the high rates of community transmission. Interrupting the shedding of SARS-CoV-2 may reduce the incidence of Coronavirus Disease 19 (COVID-19). Herein we provide a protocol for a cluster randomized trial that will examine the effectiveness of treatment with interferon (IFN) ß-1a compared to standard of care in limiting the transmission of SARS-CoV-2. Co-primary objectives are to determine whether IFN therapy reduces (a) the proportion of infected cases shedding SARS-CoV-2 at day 11 post randomization and (b) the incidence of transmission of SARS-CoV-2 infection from index cases to treatment-eligible household post-exposure contacts at day 11 after randomization. Secondary objectives include assessing the impact of IFN treatment on duration of viral clearance, hospitalizations and fatalities, and evaluating the safety of IFN treatment. METHODS: Three hundred and ten households, each including an index case with a recent COVID-19 diagnosis and at least one asymptomatic treatment-eligible household contact, will be randomized to receive 3 doses of 125 µg IFN ß-1a by subcutaneous administration (days 1, 6, and 11), or standard of care. All participants will be followed until day 29. DISCUSSION: The results from this trial will identify whether IFN ß treatment of mild or moderate COVID-19 cases accelerates viral clearance and prevents disease progression and whether IFN ß treatment of post-exposure contacts of COVID-19 cases reduces transmission of infection. TRIAL REGISTRATION: This trial is registered at ClinicalTrials.gov NCT04552379; date of registration September 17, 2020.

The relationship between fluid biomarkers and clinical outcomes in sports-related concussions: a systematic review.

OBJECTIVES: The literature on fluid biomarkers for concussion has primarily focused on comparing athletes with and without a diagnosis of concussion and on examining the relationship between fluid biomarkers and exposure to head trauma. This systematic literature review aims to examine the strength of evidence for fluid biomarkers to be associated with clinically relevant outcomes in sports-related concussion. METHODS: A systematic literature review was conducted using EmBASE, PubMed, and CINAHL. English-language articles that included athletes participating in organized sports and reported the relationship between at least one fluid biomarker and at least one clinical outcome measure, or provided data that could be used to analyze this relationship, were included. RESULTS: Studies of the relationship between fluid biomarkers and clinical outcomes of concussion have yielded small or variable effects. There were significant inconsistencies in methodology including duration of time post-injury of biomarker collection, use of control groups, the number of time points post-injury that biomarkers were collected, and what clinical outcomes were utilized. CONCLUSION: There is currently insufficient evidence to support a relationship between any of the included fluid biomarkers and clinical outcome measures of concussion. Future research including clinical outcome measures and using standardized study design and methodology is necessary.

Multidisciplinary Concussion Management: A Model for Outpatient Concussion Management in the Acute and Post-Acute Settings.

OBJECTIVE: To describe a model of multidisciplinary concussion management and explore management methods in the acute and post-acute settings. SETTING: A multidisciplinary concussion management program within a large health system. PARTICIPANTS: Patients with sports and non-sports-related concussions aged 14 to 18 years with persisting concussion symptoms at 4 weeks postinjury or beyond. DESIGN: Pilot randomized controlled trial comparing a subsymptom threshold exercise program with standard-of-care treatment in the post-acute setting. MAIN MEASURES: Beck Depression Inventory-II and the Post-Concussion Scale-Revised. RESULTS: Across groups, 60% improvement in concussion symptoms was noted. After removing the influence of depression, the intervention showed a large effect on symptom reduction, with participants in the intervention group improving more than those in the control group. There was no difference in response to the intervention by the sports and nonsports groups. CONCLUSION: Results demonstrate that exercise intervention is effective in reducing symptoms in adolescents with persisting symptoms. The finding that participants in the control group who underwent education, light activity, and sophisticated monitoring still had meaningful recovery supports the utility of active engagement in a multidisciplinary management program. Finally, depression had a clinically meaningful effect on recovery, highlighting the need for targeted intervention of noninjury factors relevant to persisting symptoms.

Estimating a Representative Value and Proportion of True Zeros for Censored Analytical Data with Applications to Contaminated Site Assessment.

This paper demonstrates a maximum likelihood (ML)-based approach to derive representative ("best guess") contaminant concentrations from data with censored values (e.g., less than the detection limit). The method represents an advancement over existing techniques because it is capable of estimating the proportion of measurements that are true zeros and incorporating varying levels of censorship (e.g., sample specific detection limits, changes through time in method detection). The ability of the method to estimate the proportion of true zeros is validated using precipitation data. The stability and flexibility of the method are demonstrated with stochastic simulation, a sensitivity analysis, and unbiasedness analysis including varying numbers of significant digits. A key aspect of this paper is the application of the statistical analysis to real site rock core contaminant concentration data collected within a plume at two locations using high resolution depth-discrete sampling. Comparison of the representative values for concentrations at each location along the plume center-line shows a larger number of true zeros and generally lower concentrations at the downgradient location according to the conceptual site model, leading to improved estimates of attenuation with distance and/or time and associated confidence; this is not achievable using deterministic methods. The practical relevance of the proposed method is that it provides an improved basis for evaluating change (spatial, temporal, or both) in environmental systems.

A generic approach to estimate airborne concentrations of substances released by indoor spray processes using a deterministic 2-box model.

Sprays are used both in workplace and consumer settings. Although spraying has advantages, such as uniform distribution of substances on surfaces in a highly efficient manner, it is often associated with a high inhalation burden. For an adequate risk assessment, this exposure has to be reliably quantified. Exposure models of varying complexity are available, which are applicable to spray applications. However, a need for improvement has been identified. In this contribution, a simple 2-box approach is suggested for the assessment of the time-weighted averaged exposure concentration (TWA) using a minimum of input data. At the moment, the model is restricted to binary spray liquids composed of a non-volatile fraction and volatile solvents. The model output can be refined by introducing correction factors based on the classification and categorization of two key parameters, the droplet size class and the vapor pressure class of the solvent, or by using a data set of experimentally determined airborne release fractions related to the used spray equipment. A comparison of model results with measured data collected at real workplaces showed that this simple model based on readily available input parameters is very useful for screening purposes. The generic 2-box spray model without refinement overestimates the measurements of the considered scenarios in approximately 50% of the cases by more than a factor of 100. The generic 2-box model performs better for room spraying than for surface spraying, as the airborne fraction in the latter case is clearly overestimated. This conservatism of the prediction was significantly reduced when correction factors or experimentally determined airborne release fractions were used in addition to the generic input parameters. The resulting predictions still overestimate the exposure (ratio tool estimate to measured TWA > 10) or they are accurate (ratio 0.5-10). If the available information on boundary conditions (application type, equipment) does not justify the usage of airborne release fraction, room spraying should be used resulting in the highest exposure estimate. The model scope may be extended to (semi)volatile substances. However, acceptance may be compromised by the limited availability of measured data for this group of substances and thus may have limited potency to evaluate the model prediction.

Assessing the multifaceted cervix: examining cervical gland area at cervical length screening to predict spontaneous preterm birth.

BACKGROUND: Biologically active cervical glands provide a mucous barrier while influencing the composition and biomechanical strength of the cervical extracellular matrix. Cervical remodeling during ripening may be reflected as loss of the sonographic cervical gland area. As sonographic cervical length remains suboptimal for universal screening, adjunctive evaluation of other facets of the mid-trimester cervix may impart additional screening benefit. OBJECTIVE: To sonographically assess the cervical gland area at universal cervical length screening for preterm birth. STUDY DESIGN: We performed a retrospective cohort study of singletons with transvaginal cervical length screening universally performed during anatomic survey between 18 0/7 and 23 6/7 weeks and subsequent live delivery at a single institution in 2018. Uterine anomalies, cerclage, suboptimal imaging, or medically indicated preterm birth were excluded. Ultrasound images were assessed for cervical length and cervical gland area (with quantitative measurements when present). The primary outcome was spontaneous preterm birth <37 weeks. Absent and present gland groups were compared using χ2, Fisher's exact, T-test, and multivariate logistic regression (adjusting for parity and progesterone use, as well as the gestational age, cervical length, and gland absence at screening ultrasound). Gland measurements were evaluated using the Mann-Whitney-U Test and Spearman's correlation. RESULTS: Among the cohort of 772 patients, absent and present CGA groups were overall similar. Patients were on average 33 years old, ∼20 weeks gestation at screening ultrasound, and overall, 2.5% had history of prior spontaneous preterm birth. The absent gland group was more likely to have been taking progesterone (17% vs 4%, P=.04). Overall rate of preterm birth was 2.6%. However, the 2.3% of patients with absent cervical gland area were significantly more likely to deliver <37 weeks (aOR 23.9, 95% CI 6.4-89, P<.001). Multivariate logistic regression demonstrated better performance of a cervical length screening model for preterm birth prediction with the addition of qualitative gland evaluation (P<.001). Qualitative gland assessment was reproducible (PABAK 0.89), but quantitative gland measurements did not correlate with preterm birth. CONCLUSION: Qualitative gland absence at mid-gestation cervical length screening was associated with subsequent spontaneous preterm birth, whereas quantitative gland measurements were not. Multifaceted ultrasound screening may be needed to adequately evaluate the multiple biologic functions of the cervix.

A new unique form of microRNA from human heart, microRNA-499c, promotes myofibril formation and rescues cardiac development in mutant axolotl embryos.

BACKGROUND: A recessive mutation "c" in the Mexican axolotl, Ambystoma mexicanum, results in the failure of normal heart development. In homozygous recessive embryos, the hearts do not have organized myofibrils and fail to beat. In our previous studies, we identified a noncoding Myofibril-Inducing RNA (MIR) from axolotls which promotes myofibril formation and rescues heart development. RESULTS: We randomly cloned RNAs from fetal human heart. RNA from clone #291 promoted myofibril formation and induced heart development of mutant axolotls in organ culture. This RNA induced expression of cardiac markers in mutant hearts: tropomyosin, troponin and α-syntrophin. This cloned RNA matches in partial sequence alignment to human microRNA-499a and b, although it differs in length. We have concluded that this cloned RNA is unique in its length, but is still related to the microRNA-499 family. We have named this unique RNA, microRNA-499c. Thus, we will refer to this RNA derived from clone #291 as microRNA-499c throughout the rest of the paper. CONCLUSIONS: This new form, microRNA-499c, plays an important role in cardiac development.

The influence on DNA damage of glycaemic parameters, oral antidiabetic drugs and polymorphisms of genes involved in the DNA repair system.

The hyperglycaemia seen in type 2 diabetes mellitus (DM2) is associated with increased oxidative stress and production of reactive oxygen species, both of which are factors that can provoke DNA damage. Notwithstanding, other factors, including medications and individual susceptibility, can also induce this type of DNA lesion. The objective of this study was, therefore, to investigate the influence of glycaemic control, oral antidiabetic drugs (metformin and glibenclamide) and polymorphisms of the XRCC1 and XRCC3 genes on the frequency of DNA damage in DM2 patients, which was accessed by the cytokinesis-block micronucleus cytome and the comet assays on the ex vivo mitogenically stimulated lymphocytes. The 53 people recruited to take part in the study were already on treatment with metformin and were followed for 5 months. Ten of these patients were put on combined treatment with the addition of glibenclamide. It was observed that the greater the plasma metformin concentration, the lower the frequency of micronuclei (MN) in the sample total (P = 0.009) and also that the subset of patients using combined treatment including glibenclamide had a significantly higher MN rate 90 days after starting combined treatment (P = 0.024). In the subset who only took metformin, the rate of MN was significantly higher among carriers of the 399Gln allele on the XRCC1 gene (P = 0.008). In addition, homozygotes for the 241Thr allele exhibited a significant increase in MN in the combined treatment group (P = 0.008). Our results suggest that different combinations of oral antidiabetic drugs and polymorphisms on genes involved in the DNA damage repair system could influence the frequency of this type of chromosome lesion, which can be a useful biomarker for assessing the risk of developing cancer.

Prenatal diagnosis of Bardet Biedl Syndrome: A case report.

The Bardet-Biedl Syndrome (BBS), also called Laurence-Moon-Bardet-Biedl syndrome is a rare ciliopathic autosomal recessive genetic defect. BBS phenotype develops over the years and diagnosis is usually made in late childhood or early adulthood. Prenatal diagnosis is rare in absence of family history or consanguinity. The major features of this syndrome are cone-rod dystrophy, obesity, polydactyly, learning disabilities, hypogonadism in males, renal anomalies, nystagmus, speech disorders, developmental delay and ataxia. At least 20 BBS genes have been identified and all are involved in primary cilia functioning. Genetic diagnosis includes multigene sequencing technologies. Clinical management includes symptomatic treatment. In our case report, we present a case of a baby born to parents of Bengali Asian ancestry with high clinical suspicion of BBS based on fetal magnetic resonance imaging findings done during antepartum surveillance.

A mixed-methods evaluation of the ¡Vamos por Más! parenting program implementation in Chile.

INTRODUCTION AND AIMS: Substance use is a significant global concern. Strengthening parenting in families with adolescents has been shown to reduce substance use initiation. The ¡Vamos por Más! (¡VxM!) program is a positive-parenting program developed in Chile to improve family relations and reduce adolescent substance use that combines in-person school workshops, multimedia messaging and personalized support. This manuscript reports a mixed-methods evaluation of the pilot implementation of the ¡VxM! program utilizing the Consolidated Framework for Implementation Research and Proctor's taxonomy for process outcomes. METHODS: An explanatory sequential design was used. Quantitative methods evaluated program use, acceptability, appropriateness, and fidelity, and were followed by qualitative focus groups (FGs) to assess the implementation process and understand these outcomes. Thirteen FGs stratified by school and role, including school leaders, program facilitators, participants, and researchers, were conducted. RESULTS: The program was implemented in three schools, reaching 253 families with in-person workshops (40.5% of potential participants), 257 parents who viewed on average 72.1% of sent multimedia messages, and 2 families who used the personalized support (0.3%). Overall, the program was viewed as acceptable and appropriate by participants and implementers due to the high quality of program materials, targeted content, and activities. Implementation differed by schools. Key implementation factors were the outer context, inner school setting, and implementation processes. CONCLUSIONS: This comprehensive evaluation, including both intervention implementers and participants, identified implementation facilitators, barriers, and outcomes. Future ¡VxM! implementations should alter program components of schools with lower engagement to improve program implementation and outcomes.

Fever, Rash, and Cough in a 7-Year-Old Boy.

A 7-year-old boy presented to the emergency department with fever, cough, congestion, abdominal pain, myalgias, and morbilliform rash. Several aspects of the patient's history, including recent travel, living on a farm, exposure to sick contacts, and new medications, resulted in a wide differential diagnosis. Initial laboratory testing revealed leukocytosis with neutrophilia and elevated atypical lymphocytes, but did not reveal any infectious causes of illness. He was discharged from the hospital, but then represented to the emergency department a day later with worsening rash, continued fever, abdominal pain, and poor intake. He was then admitted. A more comprehensive laboratory evaluation was initiated. During this hospital course, the patient's physical examination changed when he developed head and neck edema, and certain laboratory trends became clearer. With the assistance of several specialists, the team was able to reach a more definitive diagnosis and initiate treatment to appropriately manage his condition.

Dechlorinating microorganisms in a sedimentary rock matrix contaminated with a mixture of VOCs.

Microbiological characterizations of contaminant biodegradation in fractured sedimentary rock have primarily focused on the biomass suspended in groundwater samples and disregarded the biomass attached to fractures and in matrix pores. In fractured sedimentary rock, diffusion causes nearly all contaminant mass to reside in porous, low-permeability matrix. Microorganisms capable of contaminant degradation can grow in the matrix pores if the pores and pore throats are sufficiently large. In this study, the presence of dechlorinating microorganisms in rock matrices was investigated at a site where a fractured, flat-lying, sandstone-dolostone sequence has been contaminated with a mixture of chlorinated and aromatic hydrocarbons for over 40 years. The profile of organic contaminants as well as the distribution and characterization of the microbial community spatial variability was obtained through depth-discrete, high-frequency sampling along a 98-m continuous rock core. Dechlorinating microorganisms, such as Dehalococcoides and Dehalobacter, were detected in the rock matrices away from fracture surfaces, indicating that biodegradation within the rock matrix blocks should be considered as an important component of the system when evaluating the potential for natural attenuation or remediation at similar sedimentary rock sites.

A New Model Algorithm for Estimating the Inhalation Exposure Resulting from the Spraying of (Semi)-Volatile Binary Liquid Mixtures (SprayEva).

The spraying of liquid multicomponent mixtures is common in many professional and industrial settings. Typical examples are cleaning agents, additives, coatings, and biocidal products. In all of these examples, hazardous substances can be released in the form of aerosols or vapours. For occupational and consumer risk assessment in regulatory contexts, it is therefore important to know the exposure which results from the amount of chemicals in the surrounding air. In this research, a mechanistic mass balance model has been developed that covers the spraying of (semi)-volatile substances, taking into account combined exposure to spray mist, evaporation from droplets, and evaporation from surfaces as well as the nonideal behaviour of components in liquids and backpressure effects. For wall-spraying scenarios, an impaction module has been developed that quantifies the amount of overspray and the amount of material that lands on the wall. Mechanistically, the model is based on the assumption that continuous spraying can be approximated by a number of sequentially released spray pulses, each characterized by a certain droplet size, where the total aerosol exposure is obtained by summation over all release pulses. The corresponding system of differential equations is solved numerically using an extended Euler algorithm that is based on a discretisation of time and space. Since workers typically apply the product continuously, the treated area and the corresponding evaporating surface area grows over time. Time-dependent concentration gradients within the sprayed liquid films that may result from different volatilities of the components are therefore addressed by the proposed model. A worked example is presented to illustrate the calculated exposure for a scenario where aqueous solutions of H2O2 are sprayed onto surfaces as a biocidal product. The results reveal that exposure to H2O2 aerosol reaches relevant concentrations only during the spraying phase. Evaporation from sprayed surfaces takes place over much longer time periods, where backpressure effects caused by large emission sources can influence the shape of the concentration time curves significantly. The influence of the activity coefficients is not so pronounced. To test the plausibility of the developed model algorithm, a comparison of model estimates of SprayExpo, SprayEva, and ConsExpo with measured data is performed. Although the comparison is based on a limited number (N = 19) of measurement data, the results are nevertheless regarded as supportive and acceptable for the plausibility and predictive power of SprayEva.