Phosphorus Retention and Transformation in Floodplain Forests of the Southeastern United States

Phosphorus (P) commonly limits productivity in freshwater ecosystems; thus, increased P loading, either in dissolved (DP) or particulate (PP) form, can lead to eutrophication. The central goal of my dissertation research is to understand these biogeochemical mechanisms of P retention and transformation in rivers and streams and their associated FFs in the Atlantic Coastal Plain of the southeastern US (VA, NC, SC, GA).;To assess the nature of P removal during flooding events, I conducted a detailed study of DP and PP forms (inorganic, Pi and organic, Po) in waters from alluvial (AL) and blackwater (BW) FFs. At each FF site, floodwaters were collected both from the river inflow point (RI), from within the floodplain (FP) near the outflow point, and analyzed P forms by 31P nuclear magnetic resonance (NMR) spectroscopy. In both AL and BW samples, total DP and dissolved orthophosphate (DP i) declined significantly from RI to FP, while dissolved pyrophosphate (complex DPi) and total DPo were significantly higher in FP than in RI waters. Orthophosphate monoesters comprised the majority of the DPo pool and were significantly higher in FP floodwaters in both AL and BW systems. This suggests that in both AL and BW systems, DPi was converted to DPo form during flooding events, reducing its bioavailability and potential to cause the eutrophication of downstream waters.;In a second study, I added 32Pi dissolved in river water to soil cores collected AL and BW FFs to identify specific mechanisms of P retention and transformation during flooding. As much as 77 % of added 32Pi was transformed to 32Po within 2 h of addition in BW river waters, while in AL river waters, all added 32Pi remained in inorganic form. However, when labeled river waters were added to soil cores, upon contact with the soil surface, additional transformation was observed resulting in an increase in the proportion of 32Po in headwaters, averaging 68 and 80 % of total 32P recovered in AL and BW cores, respectively. These results suggest that floodplain soils act as a second line of defense protecting water quality, by retaining P inputs that are not initially transformed within the water column (river- and head-waters) during flooding events.;In a third study, I compare changes in microbial community composition in AL and BW FFs. Soil chemical properties reveal that total P (TP) concentrations were significantly higher in AL compared to BW soils, whereas total C (TC) was significantly higher in BW compared to AL FF soils. Similarly, the bacterial and fungal community composition was taxonomically different in AL compared BW FF soils. Detrended correspondence analyses of the microbial profiles and the subsequent fitting of environmental variables to ordination plots, revealed that TP and pH were associated with the composition of bacterial and fungal communities in AL soils, whereas, TC was strongly correlated with the microbial community profiles in BW FFs. These results indicate that differences in FF type (AL vs. BW) are associated with differences in soil TC, TP and pH, that are important predictors of microbial composition.;My findings clearly indicate that FFs are indeed valuable ecosystems that have profound effects on the biogeochemical retention and transformation of excess P loadings carried with floodwaters, playing an important role in maintaining water quality in downstream aquatic ecosystems. It is forecasted that by 2025 as much as two-thirds (an estimated 5 out of the 8 billion people) of the world population will experience severe water scarcity due to climate change impacts and poor water quality resulting from the eutrophication of potable freshwater reservoirs. North America is likely to be impacted by these trends, and as such future policy decisions may be dependent on the prioritization of riparian wetlands (particularly FFs) based on their ecosystems functions and values. (Abstract shortened by UMI.)

The Nasal Obstruction Balance Index: A Novel Approach to Improving Correlation Between Unilateral Nasal Airway Measurements and Evaluating Nasal Airway Asymmetry

OBJECTIVES/HYPOTHESIS: Demonstrate that the Nasal Obstruction Balance Index (NOBI) model fulfils the unmet need of improving unilateral correlation between subjective and objective nasal obstruction outcome measures and identifying the more obstructed side. Improve correlation between unilateral objective nasal airway measurements (nasal inspiratory peak flow [NIPF] and acoustic rhinometry [AR]) and subjective Visual Analogue Scale for nasal obstruction (VAS-NO) scores. Improve assessment of nasal airway asymmetry by evaluating unilateral measurements both before and after the application of nasal decongestant; which the patient could better understand. NOBI represents a ratio calculated by taking the difference between left and right nasal airway measurements and divided by the maximum unilateral measurement. It is based on Poiseuille's law and aims to reduce the confounding variables which challenge nasal airway measurement. STUDY DESIGN: Prospective cohort study. METHODS: Forty-three controls and 34 patients with nasal obstruction underwent both unilateral and bilateral NIPF, AR and VAS-NO measurements; these were repeated after the application of nasal decongestant. The NOBI values for unilateral NIPF, AR, and VAS-NO were calculated both before and after decongestant. RESULTS: The correlation between unilateral NIPF and AR measurements was enhanced considerably (r = 0.57, P < .01) when NOBI was applied. The NOBI metric significantly increased the correlation between unilateral NIPF, AR, and VAS-NO scores. Postdecongestant NOBI for NIPF and AR measurements correctly identified the more obstructed side in 82.4% and 94.1% of the deviated nasal septum (DNS) cases, respectively. CONCLUSION: The NOBI model provides a better correlation between unilateral subjective and objective measurements and identifies the more obstructed side. LEVEL OF EVIDENCE: Prospective cohort study (level III) Laryngoscope, 2021

A novel technique to repair orbital roof defects: irradiated homologous cadaveric rib (Tutoplast ®) graft in a recurrent frontal sinus ossifying fibroma

Ossifying fibroma in the fronto-ethmoidal sinuses is a rare, benign condition. In symptomatic cases, surgical excision is often undertaken and bony defects may be repaired using alloplastic grafts. We present a novel method of repairing an orbital roof defect using irradiated homologous cadaveric rib (Tutoplast ®) graft, overlaid with a pericranial flap. The patient made an excellent recovery, concluding that it is a viable and safe option with lower morbidity

Risk factors for cardiovascular disease in people with idiopathic pulmonary fibrosis: a population-based study

OBJECTIVE: People with idiopathic pulmonary fibrosis (IPF) have been shown to be at an increased risk for cardiovascular (CV) disease, but reasons for this are unknown. The aim of this study was to compare the prevalence of common CV risk factors in people with IPF and the general population and establish the incidence of ischemic heart disease (IHD) and stroke after the diagnosis of IPF, controlling for these risk factors. METHODS: We used data from a large, UK primary care database to identify incident cases of IPF and matched general-population control subjects. We compared the prevalence of risk factors for CV disease and prescription of CV medications in people with IPF (before diagnosis) with control subjects from the general population and assessed the incidence of IHD and stroke in people with IPF (after diagnosis) compared with control subjects. RESULTS: We identified 3,211 cases of IPF and 12,307 control subjects. Patients with IPF were more likely to have a record of hypertension (OR, 1.31; 95% CI, 1.19-1.44), and diabetes (OR, 1.20; 95% CI, 1.07-1.34) compared with control subjects; they were also more likely to have been prescribed several CV drugs. The rate of first-time IHD events was more than twice as high in patients than control subjects (rate ratio, 2.32; 95% CI, 1.85-2.93; P &lt; .001), but the incidence of stroke was only marginally higher (P = .09). Rate ratios for IHD and stroke were not altered substantially after adjusting for CV risk factors. CONCLUSIONS: Several CV risk factors were more prevalent in people with IPF; however, this did not account for the increased rate of IHD in this group of patients

Does the presence of connective tissue disease modify survival in patients with pulmonary fibrosis?

SummaryObjectivesPrevious studies into the survival differences between individuals with idiopathic pulmonary fibrosis and those with connective tissue disease associated pulmonary fibrosis (CTD-PF) have yielded mixed results. The aim of this study is to compare the survival of individuals with CTD-PF to those with idiopathic pulmonary fibrosis clinical syndrome (IPF-CS) using data derived from The Health Improvement network, a large primary care database in the UK.MethodsIncident cases of CTD-PF and IPF-CS between the years 2000–2009 were identified. Survival analysis was performed using Kaplan–Meier methods, stratified by type of connective tissue disease. Cox regression was then used to compare mortality rates between the groups, adjusting for age, gender and year of diagnosis.ResultsA total of 324 cases of CTD-PF and 2209 cases of IPF-CS were followed up over a mean period of 2.3 years. During this period, 113 (34.9%) cases of CTD-PF and 1073 (48.6%) cases of IPF-CS died. The mortality rates for cases with CTD-PF and IPF-CS were 123.6 per 1000 person years (95%CI: 102.8–148.9) and 229.8 per 1000 person years (95% CI: 216.4–244.0) respectively. After adjusting for age, sex and year of diagnosis, cases with CTD-PF had a better prognosis compared to those with IPF-CS (HR 0.76,95%CI: 0.62–0.92).ConclusionThe prognosis of individuals with CTD-PF appears to be significantly better than those with IPF-CS, but remains an important cause of death in patients with connective tissue disease, and requires more effective treatment options

On the triplet state of poly(N-vinylcarbazole)

Triplet state properties including transient triplet absorption spectrum, intersystem crossing yields in solution at room temperature and phosphorescence spectra, quantum yields and lifetimes at low temperature as well as singlet oxygen yields were obtained for poly(N-vinylcarbazole) (PVK) in 2-methyl-tetrahydrofuran (2-MeTHF), cyclohexane or benzene. The results allow the determination of the energy value for the lowest lying triplet state and also show that triplet formation and deactivation is a minor route for relaxation of the lowest excited singlet state of PVK. In addition, they show the triplet state is at higher energy than reported heavy metal dopants used for electrophosphorescent devices, such that if this is used as a host it will not quench their luminescence.http://www.sciencedirect.com/science/article/B6TFN-4DTTJJC-7/1/b605edb9859b607f1a9b1c1348af029

Posterior Uterine Rupture Causing Fetal Expulsion into the Abdominal Cavity: A Rare Case of Neonatal Survival

Introduction. Uterine rupture is a potentially catastrophic complication of vaginal birth after caesarean section. We describe the sixth case of posterior uterine rupture, with intact lower segment scar, and the first neonatal survival after expulsion into the abdominal cavity with posterior rupture. Case Presentation. A multiparous woman underwent prostaglandin induction of labour for postmaturity, after one previous caesarean section. Emergency caesarean section for bradycardia revealed a complete posterior uterine rupture, with fetal and placental expulsion. Upon delivery, the baby required inflation breaths only. The patient required a subtotal hysterectomy but returned home on day 5 postnatally with her healthy baby. Discussion. Vaginal birth after caesarean section constitutes a trial of labour, and the obstetrician must be reactive to labour events. Posterior uterine rupture is extremely rare and may occur without conventional signs. Good maternal and fetal outcome is possible with a prompt, coordinated team response

Cardiovascular outcomes following a respiratory tract infection among adults with non-CF bronchiectasis: a general population based study

Rationale: Studies suggest that people with bronchiectasis are at increased risk of cardiovascular co-morbidities. Objectives: We aimed to quantify the relative risk of incident cardiovascular events following a respiratory tract infection amongst people with bronchiectasis. Methods: Using UK electronic primary care records, we conducted a within-person comparison using the self-controlled case series method. We calculated the relative risk of first time cardiovascular events (either first myocardial infarction [MI] or stroke) following a respiratory tract infection compared with the individual’s baseline risk. Results: Our cohort consisted of 895 individuals with non-CF bronchiectasis with a first MI or stroke and at least one respiratory tract infection. There was an increased rate of first time cardiovascular events in the 91 day period after a respiratory tract infection (Incidence Rate Ratio [IRR] 1.56; 95% CI 1.20 to 2.02). The rate of a first cardiovascular event was highest in the first three days following a respiratory tract infection (IRR 2.73, 95% CI 1.41 to 5.27). Conclusions: These data suggest that respiratory tract infections are strongly associated with a transient increased risk of first time MI or stroke amongst people with bronchiectasis. As respiratory tract infections are six times more common in people with bronchiectasis than the general population, the increased risk has a disproportionately greater impact in these individuals. These findings may have implications for including cardiovascular risk modifications in airway infection treatment pathways in this population

A Novel Liver-targeted Testosterone Therapy for Sarcopenia in Androgen Deprived Men With Prostate Cancer.

Objective: Androgen deprivation therapy (ADT) reduces muscle and bone mass, increasing frailty in men with prostate cancer. The liver mediates the whole body anabolic effects of testosterone. Based on first-pass metabolism, liver-targeted testosterone treatment (LTTT) entails oral delivery of a small dose of testosterone that does not raise peripheral blood testosterone levels. LTTT reduces blood urea and stimulates protein anabolism in hypogonadal men and postmenopausal women. We investigated whether LTTT prevents loss of lean and bone mass during ADT. Method: A 6-month, double-blind, placebo-controlled study of testosterone 40 mg/day in 50 men. Primary outcome measures were lean mass and bone mineral content (BMC). Testosterone, urea and prostate-specific antigen (PSA) were monitored. Patients were withdrawn if PSA exceeded 4 ng/mL. Results: 42 patients completed the study. Mean (95% CI) testosterone rose during LTTT but not placebo treatment [∆ 2.2 (1.3-3.0) vs -0.7 (-1.5 to 0.2) nmol/L; P < 0.01]. Mean PSA level did not change significantly during either treatment. Blood urea fell [∆ -0.4 (-0.9 to -0.1) mmol/L] during LTTT but not placebo [∆ 0.05 (-0.8 to 0.9) mmol/L]. BMC [∆ 49 (5 to 93) g; P < 0.02] and lean mass [∆ 0.8 (-0.1 to 1.7) kg; P = 0.04) increased compared to placebo. Five patients on LTTT withdrew from increased PSA levels, all returning to baseline levels. Conclusion: LTTT shows promise as a simple therapy for preventing sarcopenia and bone loss during ADT. LTTT may induce reversible PSA rise in some patients. Further studies are required to optimize LTTT dose in ADT. LTTT has potential application in other catabolic states in men and women

Virtual Support for Real-World Movement:Using Chatbots to Overcome Barriers to Physical Activity

Conversational agents (CAs, aka chatbots) for behavioral interventions have great potential to improve patient engagement and provide solutions that can benefit human health. In this study, we examined the potential efficacy of chatbots in assisting with the resolution of specific barriers that people frequently encounter when doing behavioral interventions for the purpose of increasing physical activity (PA). To do this, six common barriers (i.e., things that stand in the way of increasing PA) were targeted (e.g., stress and fatigue), we adopted domain knowledge (i.e., psychological theories and behavioral change techniques) to design six interventions aimed at tackling each of these six barriers. These interventions were then incorporated into consultative conversations, which were subsequently integrated into a chatbot. A user study was conducted on non-clinical samples (n=77) where all participants were presented with three randomly but equally distributed chatbot interventions and a control condition. Each intervention conversation addressed a specific barrier to PA, while the control conversation did not address any barrier. The outcome variables were beliefs in PA engagement, attitudes toward the effectiveness of each intervention to resolve the barrier, and the overall chatbot experience. The results showed a significant increase in beliefs of PA engagement in most intervention groups compared to the control group, and positive attitudes toward the effectiveness of the interventions in reducing their respective barriers to PA, and positive chatbot experience. The results demonstrate that theory-grounded interventions delivered by chatbots can effectively help people overcome specific barriers to PA, thereby increasing their beliefs in PA engagement. These promising findings indicate that chatbot interventions can be an accessible and widely applicable solution for a larger population to promote PA.</p