Alternative Metrics of Green Roof Hydrologic Performance: Evapotranspiration and Peak Flow Reduction

Stormwater runoff presents an issue for many urban areas, triggering sewer overflows and water body pollution. Green roofs, engineered vegetative systems that replicate the stormwater absorption properties of natural landscapes, have become an attractive strategy for attenuating stormwater runoff. Historically, green roof hydrologic research has been focused on stormwater volume retention with less emphasis on evapotranspiration (ET) and stormwater detention. ET is associated with green roof environmental benefits, including stormwater runoff attenuation and urban heat island mitigation, and is an important parameter in hydrologic and energy models. Stormwater detention limits flow rate of stormwater into sewer systems, reducing the chance of sewer overflow. The aim of this research is to investigate green roof ET and stormwater detention behavior and develop methods to predict performance based on readily available environmental data. In order to study these hydrologic performance metrics, a series of four New York City green roofs were instrumented with sensors to measure rainfall, runoff, ET, and other environmental data. The green roofs span several extensive green roof installation types, specifically the vegetated mat, built-in-place, and modular tray systems. Environmental monitoring for this analysis began in January 2009 and concluded in October 2013. In the first study, a dynamic chamber method was developed to conduct high-resolution measurements of ET. Results show that monthly ET depths range from 2.2 to 153.6 mm. Chamber results were compared to two ET estimation methods, specifically the Penman-Monteith equation and an energy balance model. Dynamic chamber results were similar to Penman-Monteith estimates; however, the Penman-Monteith equation over-predicted bottommost ET fluxes during the winter, and under-predicted peak summer fluxes. In the second study, dynamic chamber measurements were used to investigate green roof behavior and the effectiveness of various predictive models, particularly in water-limited conditions. Comparison of Hargreaves, Priestley-Taylor, Penman, and Penman-Monteith equation results to chamber measurements reveals that the Priestley-Taylor equation best estimates ET. However, the Priestley-Taylor equation can still overestimate lower fluxes and underestimate high fluxes. Application of a storage model, antecedent precipitation index, and advection-aridity model indicates that the antecedent precipitation index best estimates ET in water-stressed conditions. In the third study, 501 rainfall events were used to characterize green roof stormwater detention behavior, through analysis of event peak rainfall rate reductions. Empirical models relating event peak runoff rate to rainfall depth and peak rainfall rate were developed. Roof-specific models allow for the comparison of peak reduction behavior among roofs, while a combined model allows for designers to estimate green roof event peak rainfall reduction performance. Model application shows that the modular tray system is most effective at reducing peak rainfall rate. Overall, this research provides valuable insight into green roof hydrologic performance. Analysis of environmental data reveals not only the ET and peak rainfall rate reduction performance of green roofs, but also the environmental factors that affect performance. Additionally, predictive models for ET and peak runoff rate investigated in this dissertation can be valuable tools for researchers, practitioners, and policymakers to estimate green roof hydrologic performance

Green roof seasonal variation: comparison of the hydrologic behavior of a thick and a thin extensive system in New York City

Green roofs have been utilized for urban stormwater management due to their ability to capture rainwater locally. Studies of the most common type, extensive green roofs, have demonstrated that green roofs can retain significant amounts of stormwater, but have also shown variation in seasonal performance. The purpose of this study is to determine how time of year impacts the hydrologic performance of extensive green roofs considering the covariates of antecedent dry weather period (ADWP), potential evapotranspiration (ET0) and storm event size. To do this, nearly four years of monitoring data from two full-scale extensive green roofs (with differing substrate depths of 100 mm and 31 mm) are analyzed. The annual performance is then modeled using a common empirical relationship between rainfall and green roof runoff, with the addition of Julian day in one approach, ET0 in another, and both ADWP and ET0 in a third approach. Together the monitoring and modeling results confirm that stormwater retention is highest in warmer months, the green roofs retain more rainfall with longer ADWPs, and the seasonal variations in behavior are more pronounced for the roof with the thinner media than the roof with the deeper media. Overall, the ability of seasonal accounting to improve stormwater retention modeling is demonstrated; modification of the empirical model to include ADWP, and ET0 improves the model R 2 from 0.944 to 0.975 for the thinner roof, and from 0.866 to 0.870 for the deeper roof. Furthermore, estimating the runoff with the empirical approach was shown to be more accurate then using a water balance model, with model R 2 of 0.944 and 0.866 compared to 0.975 and 0.866 for the thinner and deeper roof, respectively. This finding is attributed to the difficulty of accurately parameterizing the water balance model

Lentivirus Display: Stable Expression of Human Antibodies on the Surface of Human Cells and Virus Particles

Background: Isolation of human antibodies using current display technologies can be limited by constraints on protein expression, folding and post-translational modifications. Here we describe a discovery platform that utilizes self-inactivating (SIN) lentiviral vectors for the surface display of high-affinity single-chain variable region (scFv) antibody fragments on human cells and lentivirus particles. Methodology/Principal Findings: Bivalent scFvFc human antibodies were fused in frame with different transmembrane (TM) anchoring moieties to allow efficient high-level expression on human cells and the optimal TM was identified. The addition of an eight amino acid HIV-1 gp41 envelope incorporation motif further increased scFvFc expression on human cells and incorporation into lentiviral particles. Both antibody-displaying human cells and virus particles bound antigen specifically. Sulfation of CDR tyrosine residues, a property recently shown to broaden antibody binding affinity and antigen recognition was also demonstrated. High level scFvFc expression and stable integration was achieved in human cells following transduction with IRES containing bicistronic SIN lentivectors encoding ZsGreen when scFvFc fusion proteins were expressed from the first cassette. Up to 10[super]6-fold enrichment of antibody expressing cells was achieved with one round of antigen coupled magnetic bead pre-selection followed by FACS sorting. Finally, the scFvFc displaying human cells could be used directly in functional biological screens with remarkable sensitivity. Conclusions/Significance: This antibody display platform will complement existing technologies by virtue of providing properties unique to lentiviruses and antibody expression in human cells, which, in turn, may aid the discovery of novel therapeutic human mAbs

Crystal structure of bis(triphenylphosphonium) hexabromadigallate(II) in the correct space group: conformational complexity in a heteroethan

Sherpa Romeo green journal. Open access article. Creative Commons Attribution 4.0 License (CC-BY) appliesThe crystal structure of [Ph3PH]2[Ga2Br6], previously described as having a disordered anion in the space group R̄ 3, has been re-determined in the correct space group P̄ 3, where it is fully ordered. Interestingly, two-thirds of the [Ga2Br6]2− dianions have an intermediate conformation with a Br–Ga–Ga–Br torsion angle of 36.91 (1)°, while the remaining is staggered as required from adopting a site with inversion symmetry. In the lattice, [Ph3PH]+ ions lie along the same threefold axes as the dianions and are oriented such that the P–H bond is directed towards a gallium atom. The phosphonium ions lie back-to-back and interact with relatively strong T-interactions between phenyl rings on adjacent cations. DFT calculations at the B3LYP/6–311+G(fd,) level have been used to determine the barriers to rotation in [Ga2X6]2− ions. For X = Cl and X = Br, the barriers are found to be very small, with values of 4.3 and 5.1 kJ mol−1 for the two halogens.Ye

Mutations in influenza A virus neuraminidase and hemagglutinin confer resistance against a broadly neutralizing hemagglutinin stem antibody

Influenza A virus (IAV), a major cause of human morbidity and mortality, continuously evolves in response to selective pressures. Stem-directed, broadly neutralizing antibodies (sBnAbs) targeting influenza hemagglutinin (HA) are a promising therapeutic strategy, but neutralization escape mutants can develop. We used an integrated approach combining viral passaging, deep sequencing, and protein structural analyses to define escape mutations and mechanisms of neutralization escape in vitro for the F10 sBnAb. IAV was propagated with escalating concentrations of F10 over serial passages in cultured cells to select for escape mutations. Viral sequence analysis revealed three mutations in HA and one in neuraminidase (NA). Introduction of these specific mutations into IAV through reverse genetics confirmed their roles in resistance to F10. Structural analyses revealed that the selected HA mutations (S123G, N460S, and N203V) are away from the F10 epitope but may indirectly impact influenza receptor binding, endosomal fusion, or budding. The NA mutation E329K, which was previously identified to be associated with antibody escape, affects the active site of NA, highlighting the importance of the balance between HA and NA function for viral survival. Thus, whole genome population sequencing enables the identification of viral resistance mutations responding to antibody-induced selective pressure.IMPORTANCE Influenza A virus is a public health threat for which currently available vaccines are not always effective. Broadly neutralizing antibodies that bind to the highly-conserved stem region of influenza hemagglutinin (HA) can neutralize many influenza strains. To understand how influenza virus can become resistant or escape such antibodies, we propagated influenza A virus in vitro with escalating concentrations of antibody and analyzed viral populations with whole genome sequencing. We identified HA mutations near and distal to the antibody binding epitope that conferred resistance to antibody neutralization. Additionally, we identified a neuraminidase (NA) mutation that allowed the virus to grow in the presence of high concentrations of the antibody. Virus carrying dual mutations in HA and NA also grew under high antibody concentrations. We show that NA mutations mediate the escape of neutralization by antibodies against HA, highlighting the importance of a balance between HA and NA for optimal virus function

3B11-N, a monoclonal antibody against MERS-CoV, reduces lung pathology in rhesus monkeys following intratracheal inoculation of MERS-CoV Jordan-n3/2012

Middle East Respiratory Syndrome Coronavirus (MERS-CoV) was identified in 2012 as the causative agent of a severe, lethal respiratory disease occurring across several countries in the Middle East. To date there have been over 1,600 laboratory confirmed cases of MERS-CoV in 26 countries with a case fatality rate of 36%. Given the endemic region, it is possible that MERS-CoV could spread during the annual Hajj pilgrimage, necessitating countermeasure development. In this report, we describe the clinical and radiographic changes of rhesus monkeys following infection with 5×106 PFU MERS-CoV Jordan-n3/2012. Two groups of NHPs were treated with either a human anti-MERS monoclonal antibody 3B11-N or E410-N, an anti-HIV antibody. MERS-CoV Jordan-n3/2012 infection resulted in quantifiable changes by computed tomography, but limited other clinical signs of disease. 3B11-N treated subjects developed significantly reduced lung pathology when compared to infected, untreated subjects, indicating that this antibody may be a suitable MERS-CoV treatment

Outcome After Surgical Stabilization of Rib Fractures Versus Nonoperative Treatment in Patients With Multiple Rib Fractures and Moderate to Severe Traumatic Brain Injury (CWIS-TBI)

BACKGROUND Outcomes after surgical stabilization of rib fractures (SSRF) have not been studied in patients with multiple rib fractures and traumatic brain injury (TBI). We hypothesized that SSRF, as compared with nonoperative management, is associated with favorable outcomes in patients with TBI. METHODS A multicenter, retrospective cohort study was performed in patients with rib fractures and TBI between January 2012 and July 2019. Patients who underwent SSRF were compared to those managed nonoperatively. The primary outcome was mechanical ventilation-free days. Secondary outcomes were intensive care unit length of stay and hospital length of stay, tracheostomy, occurrence of complications, neurologic outcome, and mortality. Patients were further stratified into moderate (GCS score, 9–12) and severe (GCS score, ≤8) TBI. RESULTS The study cohort consisted of 456 patients of which 111 (24.3%) underwent SSRF. The SSRF was performed at a median of 3 days, and SSRF-related complication rate was 3.6%. In multivariable analyses, there was no difference in mechanical ventilation-free days between the SSRF and nonoperative groups. The odds of developing pneumonia (odds ratio [OR], 0.59; 95% confidence interval [95% CI], 0.38–0.98; p = 0.043) and 30-day mortality (OR, 0.32; 95% CI, 0.11–0.91; p = 0.032) were significantly lower in the SSRF group. Patients with moderate TBI had similar outcome in both groups. In patients with severe TBI, the odds of 30-day mortality was significantly lower after SSRF (OR, 0.19; 95% CI, 0.04–0.88; p = 0.034). CONCLUSION In patients with multiple rib fractures and TBI, the mechanical ventilation-free days did not differ between the two treatment groups. In addition, SSRF was associated with a significantly lower risk of pneumonia and 30-day mortality. In patients with moderate TBI, outcome was similar. In patients with severe TBI a lower 30-day mortality was observed. There was a low SSRF-related complication risk. These data suggest a potential role for SSRF in select patients with TBI. LEVEL OF EVIDENCE Therapeutic, level IV

Broadening of Neutralization Activity to Directly Block a Dominant Antibody-Driven SARS-Coronavirus Evolution Pathway

Phylogenetic analyses have provided strong evidence that amino acid changes in spike (S) protein of animal and human SARS coronaviruses (SARS-CoVs) during and between two zoonotic transfers (2002/03 and 2003/04) are the result of positive selection. While several studies support that some amino acid changes between animal and human viruses are the result of inter-species adaptation, the role of neutralizing antibodies (nAbs) in driving SARS-CoV evolution, particularly during intra-species transmission, is unknown. A detailed examination of SARS-CoV infected animal and human convalescent sera could provide evidence of nAb pressure which, if found, may lead to strategies to effectively block virus evolution pathways by broadening the activity of nAbs. Here we show, by focusing on a dominant neutralization epitope, that contemporaneous- and cross-strain nAb responses against SARS-CoV spike protein exist during natural infection. In vitro immune pressure on this epitope using 2002/03 strain-specific nAb 80R recapitulated a dominant escape mutation that was present in all 2003/04 animal and human viruses. Strategies to block this nAb escape/naturally occurring evolution pathway by generating broad nAbs (BnAbs) with activity against 80R escape mutants and both 2002/03 and 2003/04 strains were explored. Structure-based amino acid changes in an activation-induced cytidine deaminase (AID) “hot spot” in a light chain CDR (complementarity determining region) alone, introduced through shuffling of naturally occurring non-immune human VL chain repertoire or by targeted mutagenesis, were successful in generating these BnAbs. These results demonstrate that nAb-mediated immune pressure is likely a driving force for positive selection during intra-species transmission of SARS-CoV. Somatic hypermutation (SHM) of a single VL CDR can markedly broaden the activity of a strain-specific nAb. The strategies investigated in this study, in particular the use of structural information in combination of chain-shuffling as well as hot-spot CDR mutagenesis, can be exploited to broaden neutralization activity, to improve anti-viral nAb therapies, and directly manipulate virus evolution

Rapid Probing of Biological Surfaces with a Sparse-Matrix Peptide Library

Finding unique peptides to target specific biological surfaces is crucial to basic research and technology development, though methods based on biological arrays or large libraries limit the speed and ease with which these necessary compounds can be found. We reasoned that because biological surfaces, such as cell surfaces, mineralized tissues, and various extracellular matrices have unique molecular compositions, they present unique physicochemical signatures to the surrounding medium which could be probed by peptides with appropriately corresponding physicochemical properties. To test this hypothesis, a naïve pilot library of 36 peptides, varying in their hydrophobicity and charge, was arranged in a two-dimensional matrix and screened against various biological surfaces. While the number of peptides in the matrix library was very small, we obtained “hits” against all biological surfaces probed. Sequence refinement of the “hits” led to peptides with markedly higher specificity and binding activity against screened biological surfaces. Genetic studies revealed that peptide binding to bacteria was mediated, at least in some cases, by specific cell-surface molecules, while examination of human tooth sections showed that this method can be used to derive peptides with highly specific binding to human tissue

Silicon central pattern generators for cardiac diseases

Belgium Herbarium image of Meise Botanic Garden