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1.
Sci Total Environ ; 887: 164146, 2023 Aug 20.
Article in English | MEDLINE | ID: mdl-37182767

ABSTRACT

Application of inorganic nitrogen (N) fertilizers in agriculture can increase emissions of nitrous oxide, a potent greenhouse gas, leaching of nitrate (NO3-), a groundwater contaminant hazardous to human health, and soil acidification. Soil amendment with biochar potentially mitigates these losses and undesirable outcomes. However, there have been considerable inconsistencies in reported impacts, likely owing to variable physiochemical characteristics of the biochar materials and/or the soil environment. This study methodically evaluated the impact of biochar soil incorporation on N transformation and underlying microbial processes using soils with varying biochar types, soil texture, soil moisture, and manure compost co- amendments. Laboratory incubations were conducted to monitor the fate of urea fertilizer N spiked in biochar amended and unamended soils by assaying soil ammonium (NH4+), nitrite (NO2-), and NO3- concentrations, pH, and abundances of soil nitrifiers; ammonia oxidizing bacteria and archaea (AOB and AOA) and Nitrospira with the capacity to perform complete ammonia oxidation (comammox). Soil moisture was a critical factor affecting N transformation processes, more so than biochar, but biochar did result in significantly different concentrations of N species in response to urea application. Biochar enhanced nitrification, more significantly in drier conditions and in sandy soil. Biochar offered some buffering potential in the neutral-alkaline, unsaturated soils, preventing >1 unit drop in pH compared to unamended soils. Co-application of biochar with manure composts enhanced nitrification slightly, which was evidenced by higher abundances of some soil nitrifiers at 4 weeks, although increases in nitrification rates were not statistically significant. Soil nitrifier populations tended to increase in response to a pinewood biochar, but trends differed for saturated soil, in soils of differing textures, or when different biochar materials were evaluated. Thus, when evaluating implications of biochar on the fate of mineral N fertilizer, soil moisture and other environment conditions should be considered.


Subject(s)
Nitrification , Soil , Humans , Ammonia/metabolism , Fertilizers , Manure , Oxidation-Reduction , Soil Microbiology , Archaea/metabolism
3.
N Z Med J ; 135(1555): 19-23, 2022 05 20.
Article in English | MEDLINE | ID: mdl-35728231

ABSTRACT

AIM: To describe the demographics of those presenting to Capital & Coast DHB District Nursing Service with venous leg ulcers (VLU). METHODS: Electronic records were searched between January 2015 and December 2020 for those presenting with VLU and matched to the national minimum dataset to obtain ethnicity, age at presentation and gender. Numbers were standardised against the census data for the DHB population, to allow comparison of ethnic differences. Analysis was by prioritised ethnicity: comparing Pasifika, Maori and Other. RESULTS: Of 999 patients with VLU treated by the DN service, there were 91 Maori, 114 Pasifika, and 794 other ethnicities. Five hundred and fifty-nine were female and 440 were male. Pasifika men and women were greatly over-represented with relative risks of 20 and 19, respectively. Maori men and women had lower relative risk of 6.6 and 5.0, respectively. In addition, Maori and Pasifika presented earlier, with standardised rates greater than other ethnicities in all age groups up to the age of 70. Average age at presentation for Maori was 14-16, and Pasifika 17-18 years, younger than Other. CONCLUSION: This analysis shows for the first time that Maori and Pasifika have higher rates and present earlier than those of other ethnicities. Further investigation is required to understand the causes of earlier presentation and thereby prevent VLU.


Subject(s)
Leg Ulcer , Outpatients , Ethnicity , Female , Humans , Male , Native Hawaiian or Other Pacific Islander , New Zealand/epidemiology
4.
J Am Med Inform Assoc ; 29(8): 1372-1380, 2022 07 12.
Article in English | MEDLINE | ID: mdl-35639494

ABSTRACT

OBJECTIVE: Assess the effectiveness of providing Logical Observation Identifiers Names and Codes (LOINC®)-to-In Vitro Diagnostic (LIVD) coding specification, required by the United States Department of Health and Human Services for SARS-CoV-2 reporting, in medical center laboratories and utilize findings to inform future United States Food and Drug Administration policy on the use of real-world evidence in regulatory decisions. MATERIALS AND METHODS: We compared gaps and similarities between diagnostic test manufacturers' recommended LOINC® codes and the LOINC® codes used in medical center laboratories for the same tests. RESULTS: Five medical centers and three test manufacturers extracted data from laboratory information systems (LIS) for prioritized tests of interest. The data submission ranged from 74 to 532 LOINC® codes per site. Three test manufacturers submitted 15 LIVD catalogs representing 26 distinct devices, 6956 tests, and 686 LOINC® codes. We identified mismatches in how medical centers use LOINC® to encode laboratory tests compared to how test manufacturers encode the same laboratory tests. Of 331 tests available in the LIVD files, 136 (41%) were represented by a mismatched LOINC® code by the medical centers (chi-square 45.0, 4 df, P < .0001). DISCUSSION: The five medical centers and three test manufacturers vary in how they organize, categorize, and store LIS catalog information. This variation impacts data quality and interoperability. CONCLUSION: The results of the study indicate that providing the LIVD mappings was not sufficient to support laboratory data interoperability. National implementation of LIVD and further efforts to promote laboratory interoperability will require a more comprehensive effort and continuing evaluation and quality control.


Subject(s)
COVID-19 , Clinical Laboratory Information Systems , Humans , Laboratories , Logical Observation Identifiers Names and Codes , SARS-CoV-2 , United States
5.
Appl Plant Sci ; 9(9-10): e11449, 2021.
Article in English | MEDLINE | ID: mdl-34760409

ABSTRACT

Plant root symbionts, namely mycorrhizal fungi, can be characterized using a variety of methods, but most of these rely on DNA. While Sanger sequencing still fulfills particular research objectives, next-generation sequencing currently dominates the field, thus understanding how the two methods differ is important for identifying both opportunities and limitations to characterizing fungal communities. In addition to testing sequencing methods, we also examined how roots and soils may yield different fungal communities and how disturbance may affect those differences. We sequenced DNA from ectomycorrhizal fungi colonizing roots of Pinus banksiana and found that operational taxonomic unit richness was higher, and compositional variance lower, for Illumina MiSeq-sequenced communities compared to Sanger-sequenced communities. We also found that fungal communities associated with roots were distinct in composition compared to those associated with soils and, moreover, that soil-associated fungi were more clustered in composition than those of roots. Finally, we found community dissimilarity between roots and soils was insensitive to disturbance; however, rarefying read counts had a sizeable influence on trends in fungal richness. Although interest in mycorrhizal communities is typically focused on the abiotic and biotic filters sorting fungal species, our study shows that the choice of methods to sample, sequence, and analyze DNA can also influence the estimation of community composition.

6.
Nurse Educ Today ; 87: 104357, 2020 Apr.
Article in English | MEDLINE | ID: mdl-32032837

ABSTRACT

OBJECTIVES: The exponential rise of social media (SoMe) has transformed how people connect, learn, and network. The use of SoMe in health education is in its infancy. The objective of the review was to examine the use of SoMe by healthcare students, professionals and educators to ascertain if the use of SoMe enhanced the learning experience. DESIGN: An integrative literature review was completed in February 2019. DATA SOURCES: Three databases were used to facilitate the literature search (Medline (Ovid), Cinahl, and Scopus). REVIEW METHODS: Inclusion and exclusion criteria for the literature search were applied and PRISMA guidelines followed. The search retrieved 316 citations. Forty-seven duplicate articles were removed at this stage. Titles and abstracts were screened and 215 excluded as they were not relevant. The remaining articles were assessed for eligibility and 37 were excluded for not meeting the review requirements. RESULTS: Critical Appraisal Skills Programme (CASP, 2019) checklists primarily guided the critique of the literature, with the Caldwell et al. (2011) approach used to supplement the critique of health-related research studies. 17 research studies are included in this review. Themes were developed using Braun and Clarke's (2006) approach. Five reoccurring themes emerged: communication and collaboration, a source of reference, personal development, pitfalls and ethical concerns. CONCLUSIONS: This review provides a synthesis of SoMe use in healthcare education. SoMe is an excellent educational resource which can provide advantages in education. Areas of concern were noted and the need for improved policy and guidance highlighted. Further research and education on SoMe use in healthcare education is essential for educators, students and practitioners.


Subject(s)
Communication , Health Education , Problem-Based Learning , Social Media , Faculty , Humans , Qualitative Research , Students, Health Occupations
7.
Oecologia ; 189(1): 9-19, 2019 Jan.
Article in English | MEDLINE | ID: mdl-30094634

ABSTRACT

Ectomycorrhizal fungi are an important component to ecosystem function in the boreal forest. Underlying factors influencing fungal community composition and richness, such as host identity and soil type have been studied, but interactions between these factors have been less explored. Furthermore, mixed-species stands may have additive or synergistic effects on ectomycorrhizal fungi species richness, but this effect is challenging to test on natural sites due to difficulty in finding monospecific and mixed-species stands with similar site conditions and history. Forest reclamation areas can provide an opportunity to explore some of these fundamental questions, as site conditions and history are often known and managed, with the added benefit that knowledge emerging from these studies can be used to evaluate the recovery of degraded forest landscapes. Here, we compared the richness and composition of ectomycorrhizal fungi in young single- and mixed-species stands established on a reclamation area designed to inform strategies to restore upland boreal forests disturbed by oil sands mining. Seedlings of three host tree species (Populus tremuloides, Pinus banksiana, Picea glauca) were planted in single- and mixed-species stands on three different salvaged soils (forest floor material, peat, subsoil). After four growing seasons, there was no difference in total ectomycorrhizal fungi species richness and composition in mixed- versus combined single-species stands indicating that an additive effect of host tree species prevailed early in development. However, there were compositional shifts in fungal communities across both the host tree species and the salvaged soil type, with soil type being the strongest driver.


Subject(s)
Mycobiome , Mycorrhizae , Ecosystem , Fungi , Oil and Gas Fields , Soil Microbiology , Taiga , Trees
8.
Chem Commun (Camb) ; 46(7): 1050-2, 2010 Feb 21.
Article in English | MEDLINE | ID: mdl-20126709

ABSTRACT

Unsaturated NHCs of varying steric bulk undergo a series of unusual oxidative addition and reductive elimination processes upon binding to the Pt(Me)(2) fragment.

9.
Chemistry ; 14(1): 158-68, 2008.
Article in English | MEDLINE | ID: mdl-17999393

ABSTRACT

The preparation of two series of [Cu(NHC)2]X complexes (NHC=N-heterocyclic carbene, X=PF6 or BF4) in high yields from readily available materials is reported. These complexes have been spectroscopically and structurally characterized. The activity of these cationic bis-NHC complexes in the hydrosilylation of ketones was examined, and both the ligand and the counterion showed a significant influence on the catalytic performance. Moreover, when compared with related [Cu(NHC)]-based systems, these cationic complexes proved to be more efficient under similar reaction conditions. The activation step of [Cu(NHC)2]X precatalysts towards hydrosilylation was investigated by means of 1H NMR spectroscopy. Notably, it was shown that one of the N,N'-bis(2,6-diisopropylphenyl)imidazol-2-ylidene (IPr) ligands in [Cu(IPr)2]BF4 is displaced by tBuO(-) in the presence of NaOtBu, producing the neutral [Cu(IPr)(OtBu)]. This copper alkoxide is known to be a direct precursor of an NHC-copper hydride, the actual active species in this transformation. Furthermore, reagent loading and counterion effects have been rationalized in light of the species formed during the reaction.

10.
J Am Chem Soc ; 128(12): 4101-11, 2006 Mar 29.
Article in English | MEDLINE | ID: mdl-16551119

ABSTRACT

A series of (NHC)Pd(R-allyl)Cl complexes [NHC: IPr = N,N'-bis(2,6-diisopropylphenyl)imidazol-2-ylidene, SIPr = N,N'-bis(2,6-diisopropylphenyl)-4,5-dihydroimidazol-2-ylidene; R = H, Me, gem-Me2, Ph] have been synthesized and fully characterized. When compared to (NHC)Pd(allyl)Cl, substitution at the terminal position of the allyl scaffold favors a more facile activation step. This translates into higher catalytic activity in the Suzuki-Miyaura and Buchwald-Hartwig reactions, allowing for the coupling of unactivated aryl chlorides at room temperature in minutes. In the Suzuki-Miyaura reaction, aryl triflates, bromides, and chlorides react with boronic acids using very low catalyst loading. In the N-aryl amination reaction, a wide range of substrates has been coupled efficiently; primary-, secondary-, alkyl-, or aryl-amines react in high yields with unactivated, neutral, and activated aryl chlorides and bromides. In both reactions, extremely hindered substrates such as tri-ortho-substituted biaryls and tetra-ortho-substituted diarylamines can be produced without loss of activity. Finally, the present catalytic system has proven to be efficient with as low as 10 parts-per-million (ppm) of precatalyst in the Buchwald-Hartwig reaction and 50 ppm in the Suzuki-Miyaura reaction.

13.
J Am Chem Soc ; 127(10): 3516-26, 2005 Mar 16.
Article in English | MEDLINE | ID: mdl-15755173

ABSTRACT

Reactivity and structural studies of unusual rhodium and iridium systems bearing two N-heterocyclic carbene (NHC) ligands are presented. These systems are capable of intramolecular C-H bond activation and lead to coordinatively unsaturated 16-electron complexes. The resulting complexes can be further unsaturated by simple halide abstraction, leading to 14-electron species bearing an all-carbon environment. Saturation of the vacant sites in the 16- and 14-electron complexes with carbon monoxide permits a structural comparison. DFT calculations show that these electrophilic metal centers are stabilized by pi-donation of the NHC ligands.

14.
J Am Chem Soc ; 127(8): 2485-95, 2005 Mar 02.
Article in English | MEDLINE | ID: mdl-15725003

ABSTRACT

N-heterocyclic carbene ligands IMes (1), SIMes (2), IPr (3), SIPr (4), and ICy (5) react with Ni(CO)(4) to give the saturated tricarbonyl complexes Ni(CO)(3)(IMes) (8), Ni(CO)(3)(SIMes) (9), Ni(CO)(3)(IPr) (10), Ni(CO)(3)(SIPr) (11), and Ni(CO)(3)(ICy) (12), respectively. The electronic properties of these complexes have been compared to their phosphine analogues of general formula Ni(CO)(3)(PR(3)) by recording their nu(CO) stretching frequencies. While all of these NHCs are better donors than tertiary phosphines, the differences in donor properties between ligands 1-5 are surprisingly small. Novel, unsaturated Ni(CO)(2)(IAd) (13) and Ni(CO)(2)(I(t)()Bu) (14) compounds are obtained from the reaction of Ni(CO)(4) with IAd (6) and I(t)()Bu (7). Complexes 13 and 14 are highly active toward substitution of the NHC as well as the carbonyl ligands. This has allowed the determination of Ni-C(NHC) bond dissociation energies and the synthesis of various unsaturated Ni(0) and Ni(II) complexes. Computational studies on compounds 8-14 are in line with the experimental findings and show that IAd (6) and I(t)()Bu (7) are more bulky than IMes (1), SIMes (2), IPr (3), SIPr (4), and ICy (5). Furthermore, a method based on %V(bur) values has been developed for the direct comparison of steric requirements of NHCs and tertiary phosphines. Complexes 8-14, as well as NiCl(C(3)H(5))(I(t)()Bu) (16) and NiBr(C(3)H(5))(I(t)()Bu) (17), have been characterized by X-ray crystallography.

15.
Chem Commun (Camb) ; (24): 2890-1, 2004 Dec 21.
Article in English | MEDLINE | ID: mdl-15599458

ABSTRACT

The reactivity of a N-heterocyclic carbene (NHC) with a pseudo-acid (ester in this case) is described. The product results from an unusual C-H bond activation. The structure of the product has been established by a single crystal diffraction study.

17.
Angew Chem Int Ed Engl ; 40(11): 2108-2111, 2001 Jun 01.
Article in English | MEDLINE | ID: mdl-29712201

ABSTRACT

The three most important "superbase" anionic building blocks are contained in the striking decalithium aggregate in the structure of which a single lithium atom is surrounded solely by an amide, an alkoxide, and a carbanion.

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