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1.
Front Psychol ; 14: 1235185, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37876844

RESUMEN

Drawing on systemic racism theory, white racial framing and the notion of bad faith as the connecting, justifying thread between ideals of freedom and equality and actions realizing unfreedom and inequities, this essay explores the alchemy of race, masculinity, and racialized oppression and its consequences for Black men past and present in United States society. This essay's aim is to trace the historical ideologies and cultural practices, relations, and normative standards that have contributed to, and hence must be challenged to confront, the inequitable, race-based relations of power, and privilege at the root of institutionalized injustices. To do so, this essay interrogates the dissonance of bad faith as a corrective mode of truth telling to highlight and tap the equity potential of Black men's collective, historical rejections of the White mainstream's conflicting definitions and deceptive reasonings requisite for pushing toward racial justice, healing, and peace.

2.
J Innov Card Rhythm Manag ; 12(7): 4577-4585, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34277128

RESUMEN

It has been suggested that nonselective His bundle pacing (NS-HBP) corrects terminal conduction delay in right bundle branch block by early excitation of the right ventricular free wall. A similar analysis of NS-HBP, in patients with left bundle branch block (LBBB) and left-axis deviation (LAD) has not been done. Therefore, we compared the baseline QRS parameters in LAD and LBBB during NS-HBP and selective HBP (S-HBP). In LAD patients (n = 16), NS-HBP normalized the QRS axis from -35° ± 10° to 30° ± 34° (p < 0.01) and increased the lead 1 voltage (L1V) from 0.55 ± 0.3 mV to 0.88 ± 0.2 mV (p < 0.001) without increasing the peak lateral wall activation time (PLWAT) (p = not significant). In 23 of 41 LBBB patients, NS-HBP decreased the prolonged PLWAT by 73 ms (p < 0.0001), resolved the mid-QRS notch, normalized the QRS axis, and increased the L1V from 0.5 ± 0.3 mV to 1.15 ± 0.3 mV (p < 0.0001). In the remaining 18 LBBB patients, NS-HBP did not resolve the mid-QRS notch; however, the peak septal activation time decreased by 45 ms (p < 0.0001), PLWAT decreased by 53 ms (p < 0.0001), L1V increased from 0.5 ± 0.3 mV to 0.87 ± 0.4 mV (p < 0.0001), and the QRS axis normalized. All patients who developed S-HBP at lower pacing showed uncorrected LBBB (n = 6) or LAD (n = 7). In conclusion, NS-HBP, which causes myocardial activation in advance of simultaneously initiated S-HBP, results in a paced QRS complex with a normal axis and shorter activation times and restores the L1V in patients with LAD and LBBB. In some patients, a mid-QRS notch was seen with NS-HBP, which suggests fusion with S-HBP, which conducts without LBBB correction. A higher L1V in association with a shorter PLWAT and a normal QRS axis suggests that a more organized degree of left ventricular activation occurs with NS-HBP as compared to LBBB.

3.
Pest Manag Sci ; 61(2): 179-85, 2005 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15619719

RESUMEN

Insecticides are the most commonly used tactic to control western flower thrips (WFT), Frankliniella occidentalis Pergande (Thysanoptera: Thripidae), on greenhouse cucumber. However, WFT has developed resistance to several of the insecticides presently in use. In addition, some of these insecticides adversely affect greenhouse biological control agents used to control WFT, resulting in subsequent pest resurgence. Therefore, there is a need to identify novel insecticides with unique modes of action for use in integrated pest management (IPM) programs to effectively control WFT with minimal impact on associated biological control agents. In laboratory bioassays conducted in 2001, immature and adult WFT and three associated greenhouse biological control agents: Amblyseius cucumeris Oudemans (Acarina: Phytoseiidae), Orius insidiosus Say (Hemiptera: Anthocoridae) and Encarsia formosa Gahan (Hymenoptera: Aphelinidae) were exposed to direct, direct/residual, and residual contact applications of the novel biopesticide, spinosad (Conserve 120 SC), and the industry standard for whitefly control, endosulfan (Thiodan 50 WP). In all three types of assay, spinosad was effective against immature and adult WFT life stages. It showed low toxicity to A. cucumeris, moderate toxicity to O. insidiosus and high toxicity to E formosa. Greenhouse studies involving exposure of immature and adult WFT and adult biological control agents to cucumber leaves sprayed previously with spinosad supported the laboratory data. Spinosad showed low toxicity to A. cucumeris exposed to leaves 1 day after treatment (DAT), moderate toxicity to O. insidiosus 1 and 8 DAT, and high toxicity to E. formosa up to 28 DAT. These data, along with spinosad's unique mode of action, suggest it would be a valuable reduced-risk control agent for greenhouse cucumber IPM programs.


Asunto(s)
Cucumis sativus/parasitología , Insectos/efectos de los fármacos , Insecticidas/toxicidad , Macrólidos/toxicidad , Control Biológico de Vectores/métodos , Animales , Combinación de Medicamentos , Ambiente Controlado , Ontario , Factores de Tiempo
5.
Pest Manag Sci ; 58(8): 817-24, 2002 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12192907

RESUMEN

Two strategies for controlling first-instar larvae of gypsy moth (Lymantria dispar (L)), insecticidal bait and contact insecticide applied directly to the tree trunk, were evaluated in the laboratory. Spinosad was selected as a candidate natural-product insecticide that is active both by contact and ingestion. Incorporated into artificial diet-based bait, spinosad was toxic to neonate larvae with a minimal 10-s feeding period, with an LC50 value of 20 (15-26, 95% confidence interval) mg liter-1. It was significant that neonate larvae did not discriminate between spinosad-treated and control diet. Efficacy of diet-based bait in the laboratory, however, was significantly impacted by previous exposure to diet; fed larvae did not stop at the bait and did not incur mortality, as compared to unfed larvae. Oak bark was a suitable substrate from which neonate larvae could contact spinosad residues. Spinosad applied directly to oak bark resulted in significant mortality after 1- and 4-min crawling contact exposure times (LC50 = 24 [20-29, 95% CI] and 8.7 [6.9-11, 95% CI] mg liter-1, respectively) and contact activity persisted for 2 weeks. While contact activity was more potent on glass surfaces than on oak bark, the LC50 values differed only by factors of 2.4 and 3.6, for 1- and 4-min exposures respectively.


Asunto(s)
Control de Insectos/métodos , Insecticidas/toxicidad , Larva/efectos de los fármacos , Macrólidos/toxicidad , Mariposas Nocturnas/efectos de los fármacos , Animales , Dieta , Relación Dosis-Respuesta a Droga , Combinación de Medicamentos , Conducta Alimentaria , Insecticidas/administración & dosificación , Larva/fisiología , Macrólidos/administración & dosificación , Mariposas Nocturnas/fisiología , Actividad Motora/efectos de los fármacos , Tallos de la Planta , Quercus , Factores de Tiempo , Árboles
6.
Pest Manag Sci ; 58(4): 397-404, 2002 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11975189

RESUMEN

Spinosad is a natural insecticide with potential as a novel biorational control agent for spruce budworm (Choristoneura fumiferana [Clem]), the most destructive insect defoliator of spruce and balsam fir in Canada. Concurrent terrestrial fate experiments were conducted under full coniferous canopy and in a natural opening of a mature white spruce (Piecea glauca [Moench]) plantation of central Ontario to examine the fate and persistence of spinosad in the forest floor and underlying soils. Mean initial residues of spinosyn A and D were approximately 0.2 and 0.02 microgram g-1, respectively, in thatch and exposed soils, but were substantially higher, 2.72 and 0.36 micrograms g-1, in litter under coniferous canopy. Results demonstrated that spinosad residues in spruce litter, graminaceous thatch and exposed sandy loam soils dissipated rapidly, following hyperbolic or exponential decline models. Dissipation time (DT50) values ranged from 2.0 to 7.8 days, depending on matrix and experimental conditions. Transient increases in demethylated metabolite residues confirmed that the parent product was degraded in situ. No evidence of vertical mobility of any of the analytes was observed.


Asunto(s)
Insecticidas/metabolismo , Macrólidos/metabolismo , Picea/crecimiento & desarrollo , Contaminantes del Suelo/análisis , Suelo/análisis , Antibacterianos/química , Antibacterianos/metabolismo , Combinación de Medicamentos , Agricultura Forestal , Insecticidas/química , Macrólidos/química , Modelos Biológicos , Estructura Molecular , Ontario , Residuos de Plaguicidas/química , Residuos de Plaguicidas/metabolismo
7.
J Agric Food Chem ; 50(4): 790-5, 2002 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-11829646

RESUMEN

Spinosad is a natural insecticide, produced via fermentation culture of the actinomycete Saccharopolyspora spinosa, with potential use against a number of forest pests including spruce budworm (Choristoneura fumiferana [Clem]). Persistence of spinosad was determined in terrestrial fate experiments conducted within a semimature stand of black spruce (Picea mariana [Mill.]) and balsam fir (Abies balsamea [L]) in the Acadian forest region of New Brunswick, Canada. Results of experiments established under full coniferous canopy and in a canopy opening indicated that spinosad dissipated rapidly following hyperbolic kinetics in both litter and soils and was not susceptible to leaching. Time to 50% dissipation estimates for spinosyn A ranged from 2.0 to 12.4 days depending upon matrix and experimental conditions. Spinosyn D dissipated to levels below quantitation limits (0.02 microg/g of dry mass) within 7 days in all cases. Sporadic low-level detection of the demethylated metabolites suggested that parent compounds were degraded in situ.


Asunto(s)
Macrólidos/análisis , Suelo/análisis , Árboles , Antibacterianos/análisis , Combinación de Medicamentos , Insecticidas/análisis , Cinética , Nuevo Brunswick , Análisis de Regresión
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