Rapid Macrocell Tests of Enduramet® 33, Enduramet® 316LN, and Endurament® 2205 Stainless Steel Bars

The corrosion resistance of EnduraMet® 33, EnduraMet® 316LN, and EnduraMet® 2205 stainless steel reinforcing bars is evaluated using the rapid macrocell test outlined in Annexes A1 and A2 of ASTM A955-10. Based on the test results, all three types of stainless steel satisfy the requirements of ASTM A955-10

Rapid Macrocell Tests of Enduramet® 32 Stainless Steel Bars

The corrosion resistance of EnduraMet® 32 stainless steel bars was evaluated using the rapid macrocell test outlined in Annexes A1 and A2 of ASTM A955-10. Based on the test results, the EnduraMet® 32 stainless steel bars satisfy the requirements of ASTM A955-10

Rapid Macrocell Tests of LDX 2101® Stainless Steel Bars

The corrosion resistance of LDX 2101® duplex stainless steel bars is evaluated using the rapid macrocell test specified in Annex A2 of ASTM A955-09b and compared to the performance of 2205 pickled stainless steel (2205p). LDX 2101® bars were tested in the asreceived condition as well as after submersion in simulated concrete pore solution with a pH of 13.4 for two weeks prior to testing. The LDX 2101® stainless steel bars meet the requirements of ASTM A955-09b, exhibiting limited staining and slight corrosion on the bars in salt solution with a maximum individual corrosion rate of 0.44 μm/yr and a maximum average corrosion rate of 0.10 μm/yr. No significant difference was observed in the behavior between bars tested in the as-received condition and bars tested after submersion in simulated concrete pore solution. The 2205p bars exhibited no visible corrosion products on the bars in salt solution and no measureable corrosion. Both the LDX 2101® and 2205p stainless steel bars exhibited moderate staining of the bars used as cathodes in oxygenated pore solution

Rapid Macrocell Tests of Enduramet® 2304 Stainless Steel Bars

The corrosion performance of epoxy-coated steel meeting the requirements of ASTM A775 with the coating in an undamaged condition and two damaged conditions (0.04% and 0.83% damaged area) is evaluated in accordance with Annexes A1 and A2 of ASTM 955 and compared with the corrosion performance of conventional reinforcing steel meeting the requirements of ASTM A615 steel and low-carbon, chromium steel meeting the requirements of A1035, with the latter in both the as-received and pickled conditions. Epoxy-coated bars provide significantly better corrosion performance than conventional reinforcing steel. The macrocell corrosion rates for bars with a damaged area equal to 0.04% of the area exposed to the solutions in the test are relatively low, and are, on average, similar to those observed for the undamaged epoxy-coated bars. Both undamaged and 0.04% damaged area epoxy-coated specimens meet the requirements for stainless steels specified in Annexes A1 and A2 of ASTM 955, with an average corrosion rate not exceeding 0.25 μm/yr and the corrosion rate of no individual specimen exceeding 0.50 μm/yr. The macrocell corrosion rates for bars with a damaged area equal to 0.83% of the area exposed to the solutions in the test average 1 to 1.5 μm/yr based on total bar area under the severe exposure conditions provided. Conventional and A1035 steel exhibit average values near 30 μm/yr for and 20 μm/yr, respectively. Pickling provides initial protection to A1035 steel bars, and to some bars for the duration of the test, but once corrosion initiates, corrosion appears to be similar to that observed on non-pickled bars

Rapid Macrocell Tests of ASTM A775, A615, and A1035 Reinforcing Bars

The corrosion performance of epoxy-coated steel meeting the requirements of ASTM A775 with the coating in an undamaged condition and two damaged conditions (0.04% and 0.83% damaged area) is evaluated in accordance with Annexes A1 and A2 of ASTM 955 and compared with the corrosion performance of conventional reinforcing steel meeting the requirements of ASTM A615 steel and low-carbon, chromium steel meeting the requirements of A1035, with the latter in both the as-received and pickled conditions. Epoxy-coated bars provide significantly better corrosion performance than conventional reinforcing steel. The macrocell corrosion rates for bars with a damaged area equal to 0.04% of the area exposed to the solutions in the test are relatively low, and are, on average, similar to those observed for the undamaged epoxy-coated bars. Both undamaged and 0.04% damaged area epoxy-coated specimens meet the requirements for stainless steels specified in Annexes A1 and A2 of ASTM 955, with an average corrosion rate not exceeding 0.25 μm/yr and the corrosion rate of no individual specimen exceeding 0.50 μm/yr. The macrocell corrosion rates for bars with a damaged area equal to 0.83% of the area exposed to the solutions in the test average 1 to 1.5 μm/yr based on total bar area under the severe exposure conditions provided. Conventional and A1035 steel exhibit average values near 30 μm/yr for and 20 μm/yr, respectively. Pickling provides initial protection to A1035 steel bars, and to some bars for the duration of the test, but once corrosion initiates, corrosion appears to be similar to that observed on non-pickled bars

Advancing Applied Research in Conservation Criminology Through the Evaluation of Corruption Prevention, Enhancing Compliance, and Reducing Recidivism

Concomitant with an increase in the global illegal wildlife trade has been a substantial increase in research within traditional conservation-based sciences and conservation and green criminology. While the integration of criminological theories and methods into the wildlife conservation context has advanced our understanding of and practical responses to illegal wildlife trade, there remain discrepancies between the number of empirical vs. conceptual studies and a disproportionate focus on a few select theories, geographical contexts, and taxonomic groups. We present three understudied or novel applications of criminology and criminal justice research within the fields of fisheries, forestry, and wildlife conservation. First, we highlight criminological research on the application of corruption prevention in combating the illegal wildlife trade. Corruption has increasingly been getting attention from the non-governmental sector; however, there has been limited research aimed at understanding institutional opportunity structures, local conceptualizations of corruption, and the corresponding prevention strategies within conservation contexts. Second, we discuss the pre-emptive application of compliance theories when designing and monitoring Community-Based Conservation (CBC) programs such as community forestry, non-timber forest products, and community patrol programs. Applying opportunity theory and social development strategies are two suggestions to improve the effectiveness of CBCs in forestry and beyond. Finally, we present a discussion on recidivism (i.e., repeat offending) and non-instrumental or novel responses, utilizing illegal fishing as a case study. We present two alternative methods to traditional forms of punishment: restorative justice and community-based approaches. Lastly, we will present a diversity of priority research agendas within each of these topics

Mechanism of Assembly of the Dimanganese-Tyrosyl Radical Cofactor of Class Ib Ribonucleotide Reductase: Enzymatic Generation of Superoxide Is Required for Tyrosine Oxidation via a Mn(III)Mn(IV) Intermediate

Ribonucleotide reductases (RNRs) utilize radical chemistry to reduce nucleotides to deoxynucleotides in all organisms. In the class Ia and Ib RNRs, this reaction requires a stable tyrosyl radical (Y•) generated by oxidation of a reduced dinuclear metal cluster. The Fe[superscript III][subscript 2]-Y• cofactor in the NrdB subunit of the class Ia RNRs can be generated by self-assembly from Fe[superscript II][subscript 2]-NrdB, O[subscript 2], and a reducing equivalent. By contrast, the structurally homologous class Ib enzymes require a Mn[superscript III][subscript 2]-Y• cofactor in their NrdF subunit. Mn[superscript II][subscript 2]-NrdF does not react with O[subscript 2], but it binds the reduced form of a conserved flavodoxin-like protein, NrdI[subscript hq], which, in the presence of O[subscript 2], reacts to form the Mn[superscript III][subscript 2]-Y• cofactor. Here we investigate the mechanism of assembly of the Mn[superscript III][subscript 2]-Y• cofactor in Bacillus subtilis NrdF. Cluster assembly from Mn[superscript II][subscript 2]-NrdF, NrdI[subscript hq], and O[subscript 2] has been studied by stopped flow absorption and rapid freeze quench EPR spectroscopies. The results support a mechanism in which NrdI[subscript hq] reduces O[subscript 2] to O[subscript 2]•– (40–48 s[superscript –1], 0.6 mM O[subscript 2]), the O[subscript 2]•– channels to and reacts with Mn[superscript II][subscript 2]-NrdF to form a Mn[superscript III]Mn[superscript IV] intermediate (2.2 ± 0.4 s[superscript –1]), and the Mn[superscript III]Mn[superscript IV] species oxidizes tyrosine to Y• (0.08–0.15 s[superscript –1]). Controlled production of O[subscript 2]•– by NrdI[subscript hq] during class Ib RNR cofactor assembly both circumvents the unreactivity of the Mn[superscript II][subscript 2] cluster with O[subscript 2] and satisfies the requirement for an “extra” reducing equivalent in Y• generation.National Institutes of Health (U.S.) (Grant GM81393)United States. Dept. of Defense (National Defense Science and Engineering Graduate (NDSEG) Fellowships

Genetic mechanisms of critical illness in COVID-19.

Host-mediated lung inflammation is present1, and drives mortality2, in the critical illness caused by coronavirus disease 2019 (COVID-19). Host genetic variants associated with critical illness may identify mechanistic targets for therapeutic development3. Here we report the results of the GenOMICC (Genetics Of Mortality In Critical Care) genome-wide association study in 2,244 critically ill patients with COVID-19 from 208 UK intensive care units. We have identified and replicated the following new genome-wide significant associations: on chromosome 12q24.13 (rs10735079, P = 1.65 × 10-8) in a gene cluster that encodes antiviral restriction enzyme activators (OAS1, OAS2 and OAS3); on chromosome 19p13.2 (rs74956615, P = 2.3 × 10-8) near the gene that encodes tyrosine kinase 2 (TYK2); on chromosome 19p13.3 (rs2109069, P = 3.98 ×  10-12) within the gene that encodes dipeptidyl peptidase 9 (DPP9); and on chromosome 21q22.1 (rs2236757, P = 4.99 × 10-8) in the interferon receptor gene IFNAR2. We identified potential targets for repurposing of licensed medications: using Mendelian randomization, we found evidence that low expression of IFNAR2, or high expression of TYK2, are associated with life-threatening disease; and transcriptome-wide association in lung tissue revealed that high expression of the monocyte-macrophage chemotactic receptor CCR2 is associated with severe COVID-19. Our results identify robust genetic signals relating to key host antiviral defence mechanisms and mediators of inflammatory organ damage in COVID-19. Both mechanisms may be amenable to targeted treatment with existing drugs. However, large-scale randomized clinical trials will be essential before any change to clinical practice