19 research outputs found
Nest Success and Duckling Survival of Greater Scaup, Aythya marila, at Grassy Island, New Brunswick
Nesting biology and duckling survival of Greater Scaup (Aythya marila) at Grassy Island on the Saint John River in southern New Brunswick were compared between 1995 and 1996. Grassy Island in New Brunswick is an area that is notably removed from other scaup breeding areas, being located farther south from main breeding areas in North America. The Mayfield estimates of nest success were 61% and 21% in 1995 and 1996, respectively. Mean daily survival rates were 0.99 in 1995 and 0.96 in 1996 and were significantly different (t = 4.86, P < 0.001). Duckling survival was estimated to range from 38 to 54% in 1995, and was 8% in 1996. The lower breeding success in 1996 may have been due to factors associated with decreased temperatures and increased precipitation, but the fact that the breeding location is atypical to other Greater Scaup breeding areas should not be overlooked
The decarbonization of coal tar via microwave-initiated catalytic deep dehydrogenation
Coal tar, a major by-product of the coal industry, presents considerable difficulties in its refining and conversion into fuels due to its complex chemical composition and physical properties, such as high viscosity, corrosiveness, thermal instability, etc. Here we report a new route for producing hydrogen-rich gases together with carbonaceous materials, including carbon nanotubes, through the microwave-initiated catalytic deep dehydrogenation of coal tar using inexpensive iron catalysts. The resulting carbonaceous materials generated over the catalyst were investigated using a variety of techniques including scanning electron microscopy (SEM), transmission electron microscopy (TEM), temperature programmed oxidation (TPO) and Raman spectroscopy. Importantly, we have found that an aqueous emulsion feed of the coal tar enables considerably easier handling and an enhanced hydrogen production whilst also significantly reducing the extent of catalyst deactivation. This behaviour is shown to be assisted by the phenomenon of micro-explosion that enhances mass and heat transfer during the catalytic reactions
Greater Scaup, Aythya marila, Nest Site Characteristics on Grassy Island, New Brunswick
We studied Greater Scaup (Aythya marilla) nest site selection on Grassy Island, New Brunswick, during 1995 and 1996 by describing site selection in relation to habitat characteristics and association with larids using univariate comparisons. We pooled nesting data from both years and found that nesting sites were significantly closer to larid colonies and the edge of the patch of vegetation in which the nests were situated, had less forb canopy cover, more sedge cover, greater overhead concealment and lateral cover at 0–0.25 m, and less ground moisture than random sites. We evaluated Greater Scaup nests delimited as close to or far from larid colonies at 30 m and documented that nests closer to larid colonies were found in shorter vegetation that was closer to the edge of the patch of vegetation with less lateral cover at 0.25–0.5 m, but had greater overhead concealment than nests farther away. Advancements in the ecological understanding of the species, including habitat use patterns and species associations, will increase the likelihood of conservation successes
SYNTHESES AND STRUCTURES OF [RE(SC(6)H(3)ME(2)-2,6)(3)(PPH(3))], [RE(SC(6)H(3)ME(2)-2,6)(3)(BU(T)NC)(2)], [RE(SC6H2PR3I-2,4,6)(3)L(PPH(3))] (L=N-2 OR CO) AND [REH4(PPH(3))(4)] [REO(SC6H2PR3I-2,4,6)(4)]
The hydride [ReH7(PPh(3))(2)] reacted with 2,6-dimethylbenzenethiol in toluene to give a complex of stoichiometry [Re(SC(6)H(3)Me(2)-2,6)(3)(PPh(3))] 1. A crystal structure showed a trigonal-bipyramidal geometry about the Re with Bn agostic interaction to a thiolate methyl occupying an apical site. trans to the PPh(3) ligand. Complex 1 reacts rapidly with MeCN to give the known [Re(SC(6)H(3)Me(2)-2,6)(3)(MeCN)(PPh(3))] 2 and with Bu(dagger)NC to form [Re(SC(6)H(3)Me(2)-2,6)(3)(Bu(t)NC)(2)]. 3 The crystal structure of 3 showed trigonal-pyramidal geometry about the Re with asymmetric co-ordination of the isocyanide ligands and an unusual configuration for the thiolate aromatic groups; The reactions of the hydrides [ReH7(PPh(3))(2)] and [ReH5(PPh(3))(3)] with 2,4,6-triisopropyl-. 2.6-dimethdxy-benzenethiol and tris(2-sulfanylphenyl)phosphine were also studied. With HSC6H2Pr3i-2,4,6 the dinitrogen complex [Re(SC6H2Pr3i-2,4,6)(3)(N-2)(PPh(3))] 4 was formed and its structure determined. The preparations and structures of the complexes [ReH4(PPh(3))(4)][ReO(SC6H2Pr3i-2,4,6)(4)], [Re{SC6H3(OMe)(2)-2,6}(3)(PPh(3))] and [Re{P(C6H4S-2)(3)}(PPh(3))] are also discussed. An alternative convenient route to [ReH4(PPh(3))(4)](+) from [ReH5(PPh(3))(3)] is presented
Synthesis and structural characterization of rhenium(I) tricarbonyl complexes with the bidentate ligands o-(diphenylphosphino)benzaldehyde (P∩O) and o-[(diphenylphosphino)benzylidene]analine (P∩N)
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First Demonstration Project of Long-Acting Injectable Antiretroviral Therapy for Persons With and Without Detectable Human Immunodeficiency Virus (HIV) Viremia in an Urban HIV Clinic
BackgroundLong-acting injectable antiretroviral therapy (LAI-ART) is approved for treatment-naive or experienced people with human immunodeficiency virus (HIV; PWH) based on trials that only included participants with viral suppression. We performed the first LAI-ART demonstration project to include PWH unable to achieve or maintain viral suppression due to challenges adhering to oral ART.MethodsWard 86 is a large HIV clinic in San Francisco that serves publicly insured and underinsured patients. We started patients on LAI-ART via a structured process of provider referral, multidisciplinary review (MD, RN, pharmacist), and monitoring for on-time injections. Inclusion criteria were willingness to receive monthly injections and a reliable contact method.ResultsBetween June 2021 and April 2022, 51 patients initiated LAI-ART, with 39 receiving at least 2 follow-up injections by database closure (median age, 46 years; 90% cisgender men, 61% non-White, 41% marginally housed, 54% currently using stimulants). Of 24 patients who initiated injections with viral suppression (median CD4 cell count, 706 cells/mm3), 100% (95% confidence interval [CI], 86%-100%) maintained viral suppression. Of 15 patients who initiated injections with detectable viremia (median CD4 cell count, 99 cells/mm3; mean log10 viral load, 4.67; standard deviation, 1.16), 12 (80%; 95% CI, 55%-93%) achieved viral suppression, and the other 3 had a 2-log viral load decline by a median of 22 days.ConclusionsThis small demonstration project of LAI-ART in a diverse group of patients with high levels of substance use and marginal housing demonstrated promising early treatment outcomes, including in those with detectable viremia due to adherence challenges. More data on LAI-ART in hard-to-reach populations are needed
Structural characterizations of an Re(IV) complex [ReCl4(OPPh3)2] and of an imino species [ReOCl2(PPh3)(η2-OC6H4-2-CHNH)] prepared from the reaction of [ReOCl3(PPh3)2] with salicylaldoxime
An unexpected ‘4+2’ [N3S]/[NS] rhenium(IV) complex formed upon cleavage of a Re(V) imido bond
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Demonstration Project of Long-Acting Antiretroviral Therapy in a Diverse Population of People With HIV.
BackgroundIntramuscular cabotegravir (CAB) and rilpivirine (RPV) is the only long-acting antiretroviral therapy (LA-ART) regimen approved for people with HIV (PWH). Long-acting ART holds promise for improving outcomes among populations with barriers to adherence but is only approved for PWH who have virologic suppression with use of oral ART before initiating injectables.ObjectiveTo examine LA-ART in a population of PWH that includes those with viremia.DesignObservational cohort study.SettingUrban academic safety-net HIV clinic.PatientsPublicly insured adults living with HIV with and without viral suppression, high rates of unstable housing, mental illness, and substance use.InterventionDemonstration project of long-acting injectable CAB-RPV.MeasurementsDescriptive statistics summarizing cohort outcomes to date, based on pharmacy team logs and electronic medical record data.ResultsBetween June 2021 and November 2022, 133 PWH at the Ward 86 HIV Clinic were started on LA-ART, 76 of whom had virologic suppression while using oral ART and 57 of whom had viremia. The median age was 46 years (IQR, 25 to 68 years); 117 (88%) were cisgender men, 83 (62%) had non-White race, 56 (42%) were experiencing unstable housing or homelessness, and 45 (34%) had substance use. Among those with virologic suppression, 100% (95% CI, 94% to 100%) maintained suppression. Among PWH with viremia, at a median of 33 days, 54 of 57 had viral suppression, 1 showed the expected 2-log10 reduction in HIV RNA level, and 2 experienced early virologic failure. Overall, 97.5% (CI, 89.1% to 99.8%) were projected to achieve virologic suppression by a median of 33 weeks. The current virologic failure rate of 1.5% in the cohort is similar to that across registrational clinical trials at 48 weeks.LimitationSingle-site study.ConclusionThis project demonstrates the ability of LA-ART to achieve virologic suppression among PWH, including those with viremia and challenges to adherence. Further data on the ability of LA-ART to achieve viral suppression in people with barriers to adherence are needed.Primary funding sourceNational Institutes of Health, City and County of San Francisco, and Health Resources and Services Administration